In Depth Model Discussion, Analysis and Summaries

[Gibby]

Good morning folks. Here is this morning's look at the 00z Output from GFS, UKMO, GEM and ECM for today Tuesday January 29th 2013.

All models show a unsettled spell as we move through the rest of this week. The basic pattern of West or SW winds between various Low pressures crossing close to the North of the UK and High well to the South remains until Friday with rain at times in strong and relatively mild winds, especially today mixed with cooler and more showery interludes. On Friday an active Low develops and crosses more Southern Britain with some considerable rainfall and possibly some sleet and hill snow as it engages some colder air on its Northern flank as it moves away East by Saturday. Some wintry showers on a cold Northerly wind looks likely on Saturday especially in the East as pressure builds from the NW with a ridge toppling SE over Britain late in the day followed by a warm front moving slowly East over the UK and bringing a return to milder Atlantic Westerly winds and occasional rain to end the weekend..

GFS then shows a pattern of High pressure to the SW and Low pressure areas tracking SE to the NE of Britain. Successive cold fronts will introduce spells of rather cold and showery conditions to the North and East of the UK while the South and West of Britain see only limited coolness and mostly dry weather from these as High pressure remains closer to these parts. The North, Northwest and East would no doubt see wintry showers at times while the South and West stays mostly dry and rather cloudy with short milder incursions for all as warm fronts move gently East between the pushes of colder air. Late in the run pressure builds over the UK with frosty and rather cold conditions developing for all away from the far NW.

The GFS Ensembles show a huge spread between members generally from between +5C to -5C through the second half of its output this morning. The general shift to something slightly colder than currently remains but with no sign of any sustained and marked cold pattern. Rainfall becomes limited for most areas away from the North with European locations benefiting more from the cold pool associated with SE moving depressions rather than the UK.

The Jet Stream shows the flow ridging North over the weekend around a very dominant Azores Anticyclone and down across the UK early next week suppressing any Northward movement of the High and keeping the synoptics in a static pattern.

UKMO for midnight on Monday shows a broad WNW flow over the UK with a warm front having moved East over the UK with a cloudy and generally mild flow keeping Western hills and coasts rather misty and drizzly.

GEM is much more bullish about keeping SE moving Low pressures more influential to all of the UK with rather cold or cold NW winds bringing spells of wintry showers mixed with short milder interludes as warm fronts cross around the High out to the SW with rain and sleet on the boundary edge as they move East.

ECM finally shows a spell of NW winds with rather cold conditions in the North and Northeast with wintry showers with more Southern and Western areas more cloudy and less cold with just a little occasional rain. Late in its run cold Northerly winds plunge South through the UK as a deeper Low moves down into Europe though once more it looks unsustainable as warmer air waiting to the West looks likely to topple SE in the following days.

In Summary this morning some folks in the North and East of the UK may like this morning's output as here there will be quite a lot of rather cold and unstable air around giving lengthy spells of wintry showers and perhaps some boundary snowfall as warmer air migrates East at times. Further South and West will see rather less cold conditions with High pressure close to the SW keeping fronts weak and modified as they move across at intervals giving rather cloudy and benign conditions with just a little rain at times. There is little sign of anything substantially cold an a UK wide basis this morning with the Ensembles from GFS looking less exciting today.

[Thundery wintry showers]

A fair number of points of interest on the model outputs this evening:

We have a vicious depression moving across southern parts on Friday and into Saturday (with considerable uncertainty over where it ends up). UKMO goes for a relatively shallow feature but ECMWF and more especially GFS have a very deep low with potentially damaging winds:

GFS:

http://cdn.nwstatic..../72/h500slp.png

ECMWF:

http://cdn.nwstatic..../ecm500.072.png

UKMO:

http://cdn.nwstatic....9/12/met.72.png

Following on behind we have a typical 24-36 hour northerly "toppler" which will bring some wintry showers for the usual coastal areas, maybe a few getting inland in the east for a time due to the easterly component to the wind direction, but lying snow at low levels will probably be confined to north-east Scotland with a wintry mix further south.

The models have been suggesting a chilly north-westerly around the 4th February for a few sets of runs now, and this would bring sunshine and snow showers to much of Scotland and Northern Ireland but with a wintry mix further south. Onto the 5th there is a pool of warmer air tied in with the depression core, which would turn showers back to rain and perhaps introduce a spell of cloudier and wet weather.

However, as others have noted, this evening's model runs are making rather more of this blast and the ECMWF in particular gives us a significant northerly outbreak lasting through to the 8th February- so this potential cold snap/spell is worth keeping an eye on.

[Gibby]

Good evening folks. Here's tonight's look at the 12z output from GFS, UKMO and ECM for Tuesday January 29th 2013.

All models show an agreed pattern between now and Sunday with an unsettled and blustery Westerly flow extending from now until Friday. There will be a spell of heavy rain overnight as a cold front crosses East over the UK tonight. Very strong winds will accompany the rain with severe gales in northern Scotland. Tomorrow will see fresher air in still strong winds with blustery showers rattling through on the breeze. On Thursday there will be an active squally frontal whistle through during the day with heavy showers with hail and thunder in places before things quieten down through the latter end of the day. On Friday a deepening Low looks like crossing Southern Britain with heavy rain and gales and even a little snow briefly on the back edge of the precipitation as it clears away late in the day. Saturday then sees a cold Northerly flow over the UK with wintry showers, especially in the East, dying out later. After a dry night as a ridge collapses SE over the UK Sunday will become less cold and cloudy with some rain and hill snow briefly in the North as a warm front trundles steadily East over the UK.

GFS then shows next week with a brisk and strong NW flow directing troughs SE over the UK around a deep Low moving SE to the NE of Scotland. rain would sweep SE followed by cold and windy NW winds and wintry showers in many Northern and Western areas for a time before becoming confined to the East by midweek as a new wave feature runs SE over the UK midweek with a spell of rain and hill snow giving way to further wintry showers on a cold North wind late in the week. As we move deep into FI the pressure pattern flattens with High pressure locating South of the UK with a milder SW flow setting up with Lows to the NW bringing rain at times, chiefly to Northern and Western locations.

The GFS Ensembles show a colder snap after the turn of the month moving the UK in a spell of rather colder zonality before the flow backs West again later as High pressure reverts to a position South of the UK with a flatter Westerly pattern with rain at times and uppers close to the long term mean by then.

The Jet Stream shows a flow moving NE over the UK for the coming few days before the flow tracks SE over the UK over the weekend and beyond in response to High pressure to the SW and Lows moving SE over Europe.

UKMO for midday on Monday shows a broad and rather windy WNW flow over the UK in temperatures close to normal. A lot of cloud would be fed East in the flow with some rain or drizzle over coasts and hills prior to a cold front moving SE over the UK in the period that follows.

ECM tonight is an almost mirror image to UKMO at 144hrs with a broad WNW flow blowing cloud and a little rain across the UK in temperatures broadly close to normal though it would feel cold in the wind. Rather colder air moves SE behind a depression moving ESE to the NE of Scotland bringing wintry showers SE across the UK towards midweek. The rest of the run sees cold air hanging on over the UK with North or NW winds with wintry showers, especially in the East with the chance of small disturbances running South down the Western side of the UK with rain or sleet possible at times.

In Summary tonight there is firm agreement on a spell of chilly NW winds and periods of wintry showers mixed with brief milder interludes. The weather will never become desperately cold but sufficiently cold enough for wintry showers at times, even in the South. The whole period will be accompanied by rather strong winds at times but at least total rainfall amounts will be rather less than recently.

[Gibby]

Good morning everyone. Here is this morning's look at the 00z output from GFS, UKMO, GEM and ECM for today Wednesday January 30th 2013.

All models show a similar outcome to the weather between now and the beginning of next week. Today all models show a somewhat showery Westerly flow as Low pressure exits the North taking the strongest of the winds away North with it. Tomorrow shows a showery trough moving East over Britain accentuating the showers before the weather quietens down late tomorrow and becomes somewhat colder in the North. On Friday a new Low develops as it crosses Southern Britain bringing rain to all of the South before bringing a blast of cold Northerly winds in its wake with wintry showers, especially in the East on Saturday. By Sunday the Northerly flow is shown to back Westerly as a warm front brings less cold conditions with some rain back across the UK on Sunday from the West. Early next week looks like a WNW flow will blow over the UK with the pressure gradient steepening over the UK as a deep Low lies to the NW over Iceland. The weather would be rather cloudy and increasingly windy at this point with temperatures close to normal for early February.

GFS then shows the Low sinking SE down the North Sea with another very cold blast of Northerly winds and snow showers especially in the Northwest, North and East later with the driest and least wintry conditions expected in the SW. Through the end of the week and weekend a backing of the flow towards the West once more occurs with the wintry conditions moderating as milder air slowly infiltrates from the West accompanied by a little rain or sleet as it does. Then after another flirt with a cold NW flow in the North High pressure develops from mid Atlantic across the UK towards Scandinavia settling things down slowly with cloud and any precipitation dissolving with frosty nights and decent enough days setting in by the end of the run.

The GFS Ensembles show a couple of colder bursts as we move into the weekend and again next week in an otherwise fairly average set of ensembles both for UK locations and over Europe. There will be less in the way of precipitation than recently over the South and West of Britain in particular. With most members showing winds from a NW quadrant for most of the time there will be showers about and these will be wintry at times though widespread snowfall with these temperature profiles look unlikely in the 00z period.

The Jet Stream shows the flow still programmed to ride over the displaced Azores High over the coming period and then steering the flow South over the UK and down into Southern Europe.

UKMO for midnight next Tuesday shows Low pressure over Iceland and High pressure well to the SW of Britain. A strengthening WNW flow is shown with a broad warm sector over the UK at this time with rather cloudy and breezy conditions, perhaps with a little rain. A cold front lies to the NW poised to bring a change to colder weather with Wintry showers in the period that follows the expiry of the run.

GEM today shows a similar NW flow with a tendency to bring colder and colder conditions across the UK as successive depressions move SE to the NE of the UK and eventually over and to the SE of Britain setting up an eventual cold NE wind with snow showers fr many, especially in the East with High pressure ridged NE from mid Atlantic towards Iceland at the close of the run sustaining cold onwards for a time.

ECM today shows a cold back half to next week too bringing several pushes South of cold air in association with SE moving depressions to the NE of the UK. It will deliver sleet or snow showers to many Northern and Eastern areas with the best of the drier and less wintry conditions the further SW one travels though even here some rain or sleet could occur at times as slider disturbances could run South close to the West Coast in this situation at times.

In Summary there is good agreement on a mid Atlantic High setting up with Low pressure over Europe bringing cold weather with wintry showers at times as we move into next week. What happens longer term is determined by whether we see a push North of the Azores High to more Northern latitudes increasing the longevity of the colder synoptics or whether we see a relaxing of the High to the SW and milder Atlantic air winning back. The most important thing which is easy but important to overlook is the fact that things will become less wet generally especially for Southern and Western areas and with a good drying breeze likely for large chunks of time flooded areas of the SW will have a chance to dry out somewhat.

[Gibby]

Good evening folks. Here is the evening look at the 12z output from GFS, UKMO and ECM from my perspective for this evening Wednesday January 30th 2013.

All models continue to agree on the course of events between now and the end of the weekend with just details surrounding the depth and extent of Friday's Low pressure being the difference between them. Tonight sees a further active trough move East over the UK overnight with a potentially thundery though short-lived spell of rain overnight clearing East by dawn. Tomorrow will be a day not dissimilar to today as all models show a strong Westerly flow bringing showers, chiefly in the North through the day with temperatures remaining well up to the seasonal normal. On Friday a deepening depression moves in across or just to the South of the UK with heavy rain and the chance of some hill snow here and there as well as the chance of strong winds. Later in the day the Low moves away East and leaves the UK in a cold and showery Northerly flow over Saturday with some wintry showers in the East, dying out later. On Sunday milder Atlantic winds are shown to move in from the West with some rainfall, falling as snow for a time on Northern hills.

GFS then shows next week beginning with a strong WNW flow tilting towards the North by midweek with the rather cloudy damp conditions of early in the week giving way to a spell of Northerly winds and snow showers, especially in the North and East through the midweek period. In the second half of the run the cold snap again proves short-lived as a ridge of High pressure collapses across the UK re-introducing milder Westerly winds with some rain at times, especially in the Northwest. Later in FI a further Northerly surge comes down over the UK with pressure rising over Scandinavia at the end of the run bringing snow showers and a chance of a more sustained cold spell setting up for all.

The GFS Ensembles show a colder spell for a time next week as Northerly winds take control for a while. there are signs of a recovery in uppers though later in the run as the High to the West relaxes down to the South of the UK with milder Atlantic winds returning. Rainfall quantities reduce while the colder air is in place but pick up somewhat before the end of the run under the Atlantic influence. The cold end to the operational run described above was a rank cold outlier at the time although the Control Run does offer some support.

The Jet Stream flow continues to show the flow ridging North over the Atlantic on the Northern flank of the displaced Azores High and down over the UK towards Southern Europe for the reliable future.

UKMO for midday on Tuesday shows Low pressure over the Faroe Islands with a strong and increasingly chilly WNW flow veering NNW later with increasingly wintry showers moving down over the UK over time.

ECM tonight looks broadly similar to UKMO at the same time point with an increasingly chilly WNW flow veering more towards the North brings increasingly wintry showers in strong winds SE over the UK towards the middle of next week. Through the following few days the weather turns cold as a depression moves SE over the North Sea and NW Europe steering the UK into a Northerly flow with wintry showers in the East and near Western coasts. A warm front slowly migrates into the West of the UK with some light rain and sleet with milder air following by the end of the week with the end of the run setting itself up for a re-run in the following days aided though this time with rising pressure over Scandinavia.

In Summary tonight the weather for the coming few weeks is to be governed by the movements of our old friend the Azores Anticyclone. It is shown to ridge North on occasions into mid Atlantic opening the door to some brief excursions into Northerly winds and potential snow showers before a collapsing ridge relaxes the pattern on occasions before a reload of the pattern. Late in the runs there are signs of pressure rises over Scandinavia which could open the door to rather more substantial cold weather should it evolve in 10-14 days time.

[Gibby]

Good morning. Here is this morning's take on the 00z output from GFS, UKMO, GEM and ECM for today the last day of January 2013.

All models show a strong Westerly flow blowing over the UK with a slow moving band of rain across Scotland with snow on the hills. Rain will also be exiting the SE of England through the day leaving the rest of the UK in breezy and bright conditions with just well scattered showers and temperatures close to or a little above normal. Tonight a developing Low moves East across Southern Britain and on East out of the UK tomorrow. An area of rain will move across Southern Britain overnight with a little wintriness over the hills on the Northern and Western edge of the system. Once passed the South will join other areas in a colder and more showery NW flow with some wintry showery near the East Coast for a time lasting into Saturday before dying out in association with a ridge collapsing down over the UK. A frost will develop for many on Saturday night before all models show a warm front moving in from the West on Sunday returning milder Atlantic air with some rain for all through the day.

GFS then takes us into next week with a windy couple of days with occasional rain ahead of a cold front sweeping SE across the UK on Tuesday with a cold Northerly flow developing behind with snow showers setting up over many Northern and Eastern areas as well as notorious exposed places further West such as the Cheshire Gap, Pembrokeshire and Cornwall. Late in the week a new disturbance moves East across the UK with some rain and sleet with snow over the hills moving in gradually extending milder conditions East across the UK to end the week. FI this morning shows the pattern flattening out with milder West or SW winds bringing rain at times across the UK before a return to drier conditions are shown at the end of FI and probably colder conditions too as pressure builds down from Scandinavia.

The GFS Ensembles show a couple of cold dips within the next week before a return to less cold conditions return under the effects of the Atlantic thereafter. There is a lot of spread between the members later in the run with occasional precipitation shown throughout.

The Jet Stream pattern shows the flow continuing to ridge over the Atlantic with the returning arm continuing to move down over the UK as the flow runs around the periphery of the Atlantic High area. It then moves from the UK to Southern areas of Europe maintaining the cold and unsettled conditions there.

UKMO shows a spell of breezy WNW winds early in the week with some rain at times in the North before for Low pressure slides SE to the North on Tuesday before Wednesday shows an extensive area of Low pressure over Scandinavia with an increasingly cold and unstable West veering NW airflow over the UK with rain and wintry showers extending to all areas through the day.

GEM shows a flatter pattern through the week with breezy Westerly winds. However, GEM too brings a cold and wintry blast later in the week and weekend with Low pressure slipping down over the UK and to the South with an unstable NE flow as an Atlantic High ridges NE towards Iceland.

ECM today shows a windy start to next week too with some rain for Northern areas in near normal temperatures before a cold front moves SE towards midweek with colder and more showery weather then for a few days midweek. The showers will be most wintry in the North and East with fairly dry weather in the SW apart from the risk of slider disturbances running South close to the far West at time. At the last weekend of the run though cold weather holds on with some further snow showers in the East but with a ridge crossing SE from the NW a cold, dry and frosty interlude develops for a time.

In Summary today there is going to be some cold weather to be felt for all in the next few weeks. The pattern though is very tentative with milder air never far away from the West on the Northern periphery of an Atlantic Anticyclone. These milder conditions do extend East to all of the UK at times before repeated pushes of colder air moves SE over the UK as depressions slip SE over Europe. The driest conditions look like being in Southern and Western areas closest to the influence of the Atlantic High. There is though limited support for any major wintry outbreak over the coming few weeks with temperatures by day reasonably above freezing even in the coldest areas at least by day.

[Gibby]

Good morning folks. Here is my take on the 00z outputs from GFS, UKMO, GEM and ECM for the first day of the new month (where has January gone?) Friday February 1st 2013.

All models show an agreed pattern of events over the next 4-5 days. Low pressure lies to the East of the UK with a temporary Northerly flow developing over the British Isles. Residual overnight rain will exit SE Britain this morning leaving a brighter day to develop with sunny spells later. It will feel colder with a chilly Northerly breeze developing bringing some wintry showers down the Eastern coast through the day with some rain showers too elsewhere. Tomorrow shows a Northerly flow too with a cold day in prospect with some snow showers near Eastern Coasts while most places have a dry and sunny day with a frost possible early and late. On Sunday a frontal system moves in from the West turning things less cold for a time with rain moving SE across the UK through the day. Early next week sees all models developing a chilly and strong WNW flow over the UK with rainfall and cloud slowly being replaced by sunshine and showers, these turning steadily wintry from the North with time with all areas becoming cold or rather cold by midweek in a keen Northerly wind.

GFS then gradually brings less cold conditions in from the West albeit slowly and complex with several bands of rain and sleet moving in from the West. Winds are then shown to strengthen from the West in association with deep Low pressure crossing East to the North of the UK with rain and strong winds followed by showers for all. this unsettled and windy phase then takes us out to the end of FI.

The GFS Ensembles show a rather cold spell to come under winds from a Northerly quarter. The trend is for uppers to rise to nearer the normal levels for early February in line with the operational along with an increase in rainfall.

The Jet Flow continues to track across the Atlantic over the Atlantic High and down across the UK to Southern Europe over the coming week or so.

UKMO's chart for midnight on Thursday shows Low pressure centred over Denmark with a cold Northerly flow over the UK. There would be cold weather for all in widespread snow showers for all Northern and Eastern areas in particular as well as close to Western Coastal extremities with many inland areas staying largely dry especially in the sheltered South.

GEM shows a slider Low next Thursday on the back of a Northerly flow with rain and possible snow crossing SE over the UK followed by another brief Northerly. Towards the end of it's run GEM flattens the pattern to bring milder Westerly winds in with rain and strong winds to end the run.

ECM shows a cold Northerly too through the middle of next week, weakening slowly towards the weekend as disrupting Low pressure slides SE over Britain enhancing the risk of more general rain and snow next weekend, the snow fall being totally dependant on where the Low tracks SE across the UK.

In Summary today it looks like the emphasis next week will be on rather cold and showery Northerly winds. There could be snow showers almost anywhere through the middle of the week before a slow return to something rather less cold develops later in the runs, particularly from GFS & GEM , supported by the GFS ensembles but less so from ECM. Despite these cold synoptics it's ECM's closing days pattern which could develop into a more noteworthy cold spell further down the line if pressure is shown to continue to rise over Scandinavia.

[Gibby]

Good evening folks. Thank you for all the earlier complimentary posts with reference to these twice daily reports. It's been an overwhelming verdict to maintain these reports in their present format and to keep them coming at twice daily intervals following the 00zs and 12zs. So with that in mind here's tonight's view of the 12z output from GFS, UKMO and ECM for today Friday February 1st 2013.

All models show a developing cold Northerly flow over the UK for the next 24 hours or so. By Sunday the flow will back West as a complex trough structure moves SE over the UK with rain and milder conditions for all on Sunday. Early next week shows Low pressure drifting ESE to the North of Scotland then SE over the North Sea bringing strong and increasingly cold WNW, NW and eventually North winds across the UK by midweek. Rain and sleet showers on Monday will turn increasingly to sleet and snow even in the South as we move towards midweek with frost at night but some good sunny spells too.

GFS then brings a disturbance SE across the UK with a mix of rain, sleet and snow in places before less cold air staggers its way across the UK from the West with rain at times. FI tonight shows the pattern of High pressure to the SW and Low to the North and NE continuing with winds often strong from a West or just North of West quarter with rain or showers at times. In SW areas temperatures will never be far from normal while colder outbreaks are more likely to occur towards more Northern and Northeastern areas when wintry showers become prevalent at times.

The GFS Ensembles show a rather cold spell coming early next week. However, it is not shown to last long before uppers increase to close to normal values for early February with an increasing incidence of rain at times as Atlantic Low pressures moving in from the West become more dominant.

The Jet Stream shows the usual pattern for Winter over the Northern hemisphere of the flow ridging over the Atlantic North of the Azores High and returning SE over the UK and Europe, a pattern looking like that it may not change much in the coming week or so.

UKMO for midday on Thursday shows a filling complex Low pressure area over Denmark to Eastern Europe with a slackening NNW airflow over the UK. There will be a continuation of wintry showers, though less pronounced and widespread than previous days.

ECM too shows a slackening Northerly flow with wintry showers over the UK next Thursday with Low pressure filling over Europe. the showers would be most prolific over Northern and Eastern coastal counties along with the Cheshire Gap and the SW peninsula also vulnerable. Later in its run the weather remains cold over the UK with winds still gently blowing down from the NW along with disrupting Low pressure sliding SE over the West of the UK bringing the risk of rain, sleet and snow to end the weekend.

In Summary tonight there is good agreement on a blast from the North next week but what's undecided is how long it lasts and will there be any snowfall. Well if GFS is to be believed then not long and not much would be the answers to those questions as it shows the Atlantic winning back control by the end of next week, supported by its ensembles. On the other hand ECM not unlike this morning maintains the cold component to the Northerly flow sticking around rather longer with snow showers possible on most days from midweek and the chance of something more generally wintry developing on slider lows next weekend. Of particular note from my perspective is the rise of pressure taking place over Northern Scandinavia at the end of the ECM run.

[Gibby]

Good morning folks. Here is the morning look at the 00z output from GFS, UKMO, GEM and ECM for today Saturday February 2nd 2013.

All models show reasonable agreement this morning on proceedings up to 144hrs but diversify beyond. The cold Northerly flow shown by all models for today will weaken and back West through tomorrow, Any sleet and snow showers affecting more Eastern coastal counties will die out later to leave all areas dry and sunny today but cold in a moderate Northerly wind. A frost will develop widely tonight before cloud and less cold air moves into the West early tomorrow and on Eastwards over the day tomorrow with some rain at times. Through Monday a strong WNW wind develops for all chasing any cloud and outbreaks of rain away from the South first thing so that all areas come under an increasongly cold and showery flow. As winds turn through NW and eventually Northerly over Tuesday and Wednesday it will become very cold generally with showers turning to snow for all with accumulations likely for areas exposed to the wind in the North, East and West while somee inland Central and Southern parts see few showers and stay largely dry with frost by night. Thereafter the models split in the following ways.

GFS takes us through the latter end of next week with the Northerly flow weakening as a weak front moves slowly in from the West with a little rain and sleet. High pressure will be very close to SW Britain so any precipitation here will be quite light and intermittent. A more active trough then moves into the UK from the West late in the weekend with rain moving East followed by a further round of rather cold NW winds and wintry showers for a time. FI today shows a flattening of the pattern briefly with a milder interlude with Westerly winds and occasional rain before further cold and unsettled conditions return with rain, sleet or snow at times in association with Low pressure moving SE over or later to the West of the UK and pressure building to the NE.

The GFS Ensembles show a rather cold spell for a time next week before the general consensus between the members still show an overall recovery to more normal values with rain at times. Conditions at the surface may well be rather colder than these values suggest determined by the wind flow direction at the surface later in the run.

The Jet Stream shows a continuation of the pattern currently held of the flow ridging over the Azores High and down over the UK to Southern Europe. Late in the reliable timeframe of a week there are indications the flow will buckle sufficiently North of the UK to break the flow leaving one arm travelling East over the South of Europe with the Northern arm hitting the buffers to the NE of the UK and returning SW as it hits developing High pressure to the NE over Scandinavia.

UKMO for the middle of next week shows the cold Northerly flow with snow showers gradually weakening later in the week. A front is shown to be edging in from the West then and with cold air in situ a messy transition of snow, sleet and rain looks like gradually moving East over the UK late in the week.

GEM shows the cold flow too being modified by Atlantic troughs sliding SE late next week with rain and sleet for a time before winds back West then SW with mild and unsettled weather shown over the UK by Day 10 with rain at times.

ECM keeps a feed on NW or North winds for later in the week with the midweek snow showers giving way to a period of rain, sleet and snow for a time. Then winds turn north or Northeast with sleet and snow and cold temperatures returning SW across all areas as pressure builds from the Atlantic NE to the NW of Scotland. late in the run the pressure pattern becomes complex but good for maintaining cold over the UK with High pressure having built strongly over Scandinavia with also High pressure in the Atlantic keeping UK winds from a NE or Easterly direction. With various troughs and disturbances in the air pattern sleet and snow could occur almost anywhere with frost at night.

In Summary today the general pattern looks like seeing cold Northerly winds to move down over the UK early next week with sleet or snow showers in places and frosty nights. Its longer term that things become more complex with GFS showing further SE moving Low pressure and a trend to colder synoptics late in its run while ECM is still bullish about keeping the UK locked in a generally cold pattern with some snow right out to day 10 and beyond aided by a strong pressure build to the NE. This is the third consecutive ECM run that has come up with a High pressure build to the NE in a week or so time so one has to begin to take the point seriously that the model has picked up on a trend with some latter agreement from GFS too albeit deep in FI.

[Gibby]

Good morning. Here is the report of the 00z output from GFS, UKMO, GEM and ECM for today Sunday February 3rd 2013.

All models continue to show a change to cold and windy conditions for the first half of the coming week with a moderating Northerly flow by the end of the working week. This means that after today's briefly milder and damp conditions the weather will turn windy and colder as we move through the early working days of the week with showers turning quickly wintry from the NW to all areas on Tuesday, heavy and prolonged in the North and West. Through the middle of the week as a deep Low moves down into Europe winds will turn Northerly for all and begin to decrease steadily as pressure builds from the West. Sleet and snow showers in the East and in exposure elsewhere such as the Cheshire Gap and from Pembrokeshire to Cornwall could well give accumulations in places while inland Central areas become largely dry with hard frosts at night. Late in the week all models show a disturbance on the boundary with milder air just to the West of the UK runs SE over England with rain, sleet or snow possible for a time before the cold air wins back for Friday.

GFS then shows next weekend with High pressure building across the UK with a fine and dry spell but cold with frosty nights widespread.. Further weak disturbances run into the High from the West at the start of the second week with the risk of light rain or snow for a time as it decays in the wake of a further weak ridge of High pressure which quickly gives way by midweek as Low pressure moves SE into the UK from the NW with rain and showers to all areas in a fresh wind. Cold air may still hang on towards the North and NE with some snow at times over the hills here while the South see temperatures back to near average levels.

The GFS Ensembles are firming up on a week long cold spell with good agreement on all members for the first week. As usual there is a fair scatter over week 2 though with some members continuing the cold theme a while longer before things return to near average late on. Not much precipitation in the South to speak of through week 1 but as the ingress of milder Atlantic air moves in precipitation amounts increase through week 2.

The Jet Stream shows a weakening of the flow later next week with one thrust of energy climbing High up in the Northern Atlantic and breaking down while another weaker arm is moving NE over North Africa in just over a week's time.

UKMO for midnight on Saturday shows a large but slack area of Low pressure over Europe under cold air there. A strong ridge from the Azores High is inching in towards the West of the UK which lis in a light NW flow with a few wintry showers still occurring near Northern coasts and hills though Western areas would probably see an ingress of cloud from the milder Atlantic through the day.

GEM shows a ridge moving East over the UK next weekend cutting off any cold feed and bringing the UK into a milder spell with rain at times through the start of the new week as the standard UK pattern of High to the South and Low to the North takes hold.

ECM this morning is once more something of a stand alone model this morning. It brings a cold ridge East early next weekend with the cold NE flow in the SE giving way to a dry and frosty 24 hours. By Sunday a disrupting trough and Low pressure slide SE West of the UK leading the UK in a cold pool of air. As the disrupting Low to the West pulls to the South a cold and slack NE or East flow develops with sufficient instability to give some areas occasional snowfall as pressure builds to the North and NE. By 240hrs the block of High pressure seems to be establishing well to the NE with a cold ridge developing over the UK with frosty nights and cold sunny days. With further disrupting troughs shown to the West of the UK at day 10 further snowfall could develop as it runs into the establishing cold block.

In Summary today there is good agreement on the course of evets over this week with all models showing a cold Northerly blast. It's what happens beyond that which remains unclear with ECM once more being relentless in showing a cold block of air establishing over Europe and the UK by the end of next weekend with some instability no doubt some areas would see some snowfall. GFS has moved a little towards ECM today especially imo with better support from its ensembles but is more progressive with any disrupting Low pressure beyond next weekend. UKMO looks fairly benign and non-descript this morning while GEM goes all out to bring milder air back in from the West in week 2. It looks like a blend of synoptics between GFS and ECM maybe the likely outcome but there is certainly nothing overly mild shown in this morning's output.

[Thundery wintry showers]

Some thoughts on next week and the longer-term outlook:

We are still looking at a mix of sunshine and squally wintry showers late on Monday and into Tuesday, when there could be some pretty dramatic convection about, particularly over south-western Britain, with widespread hail and scattered thunderstorms. A pool of milder air from a depression core will sweep south-eastwards late on Tuesday and into Wednesday and will turn showers back to rain and sleet, with the possibility of an area of more general, frontal-type rain tied in with it, particularly for eastern areas. Indeed, Wednesday could well end up grey, raw and wet for a time over East Anglia and the SE. Showers are likely to turn back to snow from Wednesday afternoon onwards and it is looking likely that we'll have snow showers running down the eastern side of England until Friday. We are probably looking at overnight accumulations of snow and thaws in the daytime sunshine for the majority of North Sea areas, except in areas which catch a number of heavy snow showers.

For the longer-term, we get a battle between cold continental and milder Atlantic air. The ECMWF continues to persist in showing a slack east to north-easterly flow starting next weekend, which would bring a mix of sunshine and snow showers, the majority of the showers in the east, but GFS continues to bring in Atlantic weather systems, though temperatures never really get higher than average.

My feeling is that the Scandinavian high is unlikely to go away very quickly and that we will probably end up with an easterly spell in the third week. However, there is a high likelihood of the colder air at 600-900hPa air being mixed out from the SE, resulting in stratocumulus trapped underneath a layer of dry stable air and thus predominantly dry cloudy weather, rather than frequent snow showers for eastern and central areas. I think the ECMWF would bring this scenario if it ran out beyond T+240 but we'd have a few days of sunshine and snow showers beforehand, rather than belts of frontal rain and temps of 3-6C as suggested by GFS.

[TonyH]

Weather analysis and summary for the week ahead if you live in West Wales or the Midlands:

http://forum.netweather.tv/blog/309/entry-4563-weather-guide-monday-4th-to-sunday-10th-february-2013-west-wales-and-the-midlands-only/

[Gibby]

Good morning. Here is my take on the 00z output from GFS, UKMO, GEM and ECM for today Monday February 4th 2013.

All models show good agreement on events that take us through the working week with just small subtle differences on what may happen on Friday. A developing cold and very strong WNW flow occurs over the UK today which is replacing the still relatively mild conditions in the South this morning. Wintry showers already into the NW will extend to all areas by tonight giving snowfall to some and blizzard in severe gales to the NW. Tomorrow will see a very unsettled day with sleet and snow showers early turning less wintry through the day but with a continuing NW gale. By Wednesday winds will of turned Northerly as the parent Low drifts SE down the North Sea and away into Europe. Winds will decrease steadily as the sleet and snow showers become more confined to coastal counties in the East and North as well as around Irish Sea, Welsh and Cornish coasts. By Thursday the Northerly flow will weaken further with showers close to the East Coast but dry, cold and bright conditions elsewhere probably giving way later in the day to cloudier conditions spilling down from the NW with rain, sleet and hill snow for a time which may persist into Friday before drier weather follows later Friday with cold weather hanging on for the majority of places.

GFS then shows the weekend starting with a cold and frosty ridge of High pressure kicking Saturday off before a band of rain from an Atlantic depression moves in from the West with rain and hill snow, the snow principally in the hills of the North and East. Showery weather will follow in a cold and blustery North wind, with the showers becoming wintry again for most through Monday. The specifics of FI as always are unimportant but it does suggest the rather cold weather will continue with showers or longer spells of rain at times with snow on hills under association of SE moving Low pressure areas due to high pressure away to the NE.

The GFS Ensembles show a rather colder look to them today with most members keeping 850's below the long term mean throughout much of the run. The operational was one of the colder members but there does appear less evidence of such a steep recovery of temperatures beyond the Northerly blast of this week. Precipitation amounts do show an increase though most likely indicative of SE moving Low pressure over the UK.

The Jet Stream shows a continuation of the flow pumping over the Atlantic and Southeast over the UK and on down to Southern Europe. The flow breaks up over next weekend before slipping slowly South over the Atlantic, passing to the SW of the UK and again down towards Southern Europe.

GEM today shows a ridge collapsing SE over the UK next Saturday quickly followed by Low pressure also moving SE delivering a pell of rain and hill snow to the hills of the North. This is then shown to move away SE only to be replaced by a larger, deeper Low to the North of the UK bringing rain and strong winds followed by squally showery weather in a cold West wind to end it's run.

UKMO shows a ridge of High pressure across the UK on Saturday with a cold and bright day likely. By Sunday a trough moves slowly East across the UK with rain and hill snow in the North and East moving gently in from the West through the day.

ECM finally shows the ridge too on Saturday but it shows Sunday's depression and trough further West taking the Low pressure SE to the SW of the UK meaning the rain and snow risk is held for more Southern and SW areas while the North and East see drier conditions away from snow showers near Eastern coasts. Then as High pressure builds strongly over NW Russia Low pressure continues to slide decaying troughs SE over or just to the West of the UK with milder air trying to move into the UK on repeated occasions with attendant rain and snowfall in maintained rather cold conditions.

In Summary the models look somewhat on the cold side of normal through most of the output this morning. GFS has now picked up on SE moving depressions and troughs with even GEM coming on board for a time next weekend. UKMO looks OK this morning at 144hrs as the trough looks like it would slide SE allowing pressure to build more from the NE while ECM keeps the wintry theme going that it's been showing of late with the Atlantic hitting the buffers as it comes up against the High pressure zone to the NE. With the UK once more finding itself on the boundary of milder Atlantic conditions to the West and cold potentially wintry conditions a shift in the pattern West or East of 100 miles or more could have profound differences to the weather we will experience at the surface. Much more swings West and East to this developing pattern will be no doubt shown over the coming days.

[johnholmes]

for those wanting a more sedate look at what the models are showing I'll try and keep this idea running whilst the weather promises to make things interesting.

Please do use the link below to see how much or how little the models show similar ideas at different times scales.

http://www.netweathe...modelcomp;sess=

Okay again out to about T+120 then what?

who knows which model will be nearer the mark-I'm not sure, perhaps ECMWF on past and current checks against GFS but we have little comparisons in real terms to show after the day 6=T+144 hours. No one that I know of has ever done an objective check to T+240 GFS and ECMWF, lots of comments but little proof.

AT t+144 both show a imilar size, shape and position for the upper trough south of Newfoundland but there the similarity ends. One develops a marked low the other a fair sized high at the surface. Consequently any charts after that are bound, for some considerable time, to show marked differences.

The 500mb anomaly charts for day 10, see links below

ECMWF-GFS

http://www.meteo.psu...0z/hgtcomp.html

and last evening the 6-10 day NOAA with the 8-14 also available from the link below

http://www.cpc.ncep....14day/500mb.php

At about the 10 day time frame all 3 seem to show a 500mb flow north of west into the UK with NOAA in its 8-14 showing a more westerly type.

So to me the jury is out for what may happen beyond this weekend, 50:50 I would say.

Edited February 4, 2013 by johnholmes

[Gibby]

Good morning all. Here's this morning's review of the 00z output from the big four namely GFS, UKMO, GEM and ECM for this morning Tuesday February 5th 2013.

All models show a very cold West to Northwest airflow over the UK veering Northerly over the coming 24 hours as a deep Low pressure slides South down the North Sea and away into Europe. Frequent wintry showers of rain and sleet, with hill snow in the South and sleet and snow in the North will continue through today giving some accumulations in the North. As winds veer Northerly the emphasis of showers will shift towards the East and West Coasts with many inland areas becoming cold and clear by night with a frost with compensatory bright and sunny days. Temperatures will remain below normal over the next couple of days but at least winds will decrease by Thursday. Later in the week troughs will move into the cold air and bring some outbreaks of rain or sleet and hill snow as they weaken in situ over the UK. Then the weather looks like becoming cold and dry over Saturday under a weak ridge of High pressure.

GFS then shows High pressure over Northern Scandinavia acting as a block to milder Atlantic winds pushing in from the West with the result that attempting troughs disrupt and slide SE over the UK on repeated occasions next week. The result would be rain and sleet moving into the West at times through the week with some snow possible in the colder air further East, especially on Monday when something a little more coherent is possible on the back edge of Low pressure exiting Southeast from the South. In FI today the pattern remains in situ with further pushes of Atlantic air into the UK disrupting and sliding away SE with spells of rain, sleet or snow for all in rather cold conditions away from the far SW.

The GFS Ensembles are much more solid in agreement of rather cold conditions for the UK today with tight agreement on uppers being on the low side of normal throughout. With precipitation spikes shown no doubt snow would feature on many days somewhere or another.

The Jet Stream shows the basic pattern of a ridging of the flow over the Atlantic and down over the UK towards Southern Europe remaining in place over the coming week or so with a temporary weakening and breaking up of the flow at the weekend.

UKMO for next weekend shows a weak ridge of High pressure moving SE over the UK on Saturday followed by a fall of pressure in association with a disrupting but developing Low pressure area moving SE over the UK through Sunday and Monday with rain or snow for all later in the period with the chance of significant snowfall over the hills of the South early next week.

GEM shows a similar picture at Day 6 with rain and snow a feature especially in the South early next week before the model flattens the pattern with the Atlantic steaming back in with ease to bring rain and milder air across the UK from the West by the end of its run.

ECM too shows the same Low pressure and a snowy and very cold start to next week, especially in the South before a ridge quickly replaces the cold easterly flow on the back of the snowy Low bringing drier and frosty conditions before it too shows another attempt to bring milder air in off the Atlantic with some success in the NW where rain at times would develop while the South holds on to the cold under a tenuous ridge of High pressure.

In Summary today things are tidying up between the models on the mid term events covering the start of next week. All models now show something of a major Low slipping SE bringing the potential for some significant snow in places to start next week. The South looks likely to be most at risk though the North would see some too while the SW could see some rain or sleet rather than snow. Longer term GFS keeps the pattern of disrupting Low pressure sliding SE over the UK with a similar event to next Monday's showing up again in the operational at the end of FI while ECM and more especially GEM cut off the cold East flow that develops behind next weeks Low and find a way to get the Atlantic back into at least the NW by the middle of next week or so.

[johnholmes]

Another look this morning at how the 2 main models available at the moment on Net Wx compare.

Yesterday they were pretty similar out to T+120 then diverged in a fairly big way.

The 00z run shows GFS following the same pattern at 120 and 144 that ECMWF showed yesterday. Take a look at the area south of Newfoundland, both now with the upper trough and both now with a deepish low at the surface. Yesterday GFS had a 1036mb high in the same place.

At 168 they are a bit different in the upper pattern they show, GFS has the upper ridge a shade behind ECMWF which also has it aligned more NE..

By 192 they both have moved the ridge along to about the same position, not exactly for sure but the upper trough continues to drive the ridge eastwards on both models.

They do diverge a bit more from there but overall a fair degree of agreement with the upper pattern and thus the general placement of surface feature.

By T+240 though then the overall patterns are different with ECMWF taking the flow into a general SW type pattern and GFS now holding this back.

Which is correct, who knows, but keep an eye on the next 00z output to see how the models are for 24 hours further down the line, so today’s’ T+144 becomes tomorrows’ T+120. Do the same with the 12z, compare them, doing this one gets a much better feel for how the models are developing over a longer time scale and PERHAPS that leads to a better idea of what the actual weather may show.

NOTE

Do NOT expect the surface features either to match as closely as the upper air nor for either model to have these features correct in height value or position beyond about T+96.

Link below

http://www.netweathe...modelcomp;sess=

just to add to the above, the link below shows the 500mb anomaly charts for 10 days time. Both, and this does not occur every time by any means, are quite similar if you take the black line on the above charts with the overall 500mb contours.

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

Edited February 5, 2013 by johnholmes

[keithlucky]

If i am reading the 500mb anomaly charts for 10days does this show a breakdown to westerlies around day 10 days John?

[johnholmes]

They are beginning to show some signs, GFS chiefly, ECMWF less so, just about to look at the NOAA output for this evening.

link to the NOAA output below for 6-10 and 8-14 day period

still a mixed signal it seems to me

http://www.cpc.ncep.noaa.gov/products/predictions/814day/500mb.php

Looking again it perhaps suggests more of a westerly but still on the cold side with the block too far north to have a major influence other than to keep a strong westerly flow until perhaps the northern +ve values extend south again.

I honestly would not like to call it at the moment.

Edited February 5, 2013 by johnholmes

[Gibby]

Good morning. Here is the report from the 00z output from GFS, UKMO, GEM and ECM for today Wednesday February 6th 2013.

All models show an agreed outlook for the next 4-5 days taking us through the weekend. The cold Northerly flow extending down through the UK as I type will continue through the day with the mix of rain and hill snow affecting the South clearing away South by lunchtime. As pressure builds from the NW the strength of the wind will decrease and clearing skies after dark will lead to a sharp frost away from Eastern Coasts where wintry showers will continue unabated for today and tonight. Tomorrow sees an area of cloud from an occlusion move into the cold air from the West with cloudy weather developing with rain and hill snow moving in from the West, more extensive snow likely over the North. Through Friday the occlusion weakens in situ with rain and snow dying out leaving a rather cold and non-descript few days with light winds and cold air sitting over the UK, though Saturday could be rather brighter with some sunshine. Then through Sunday a trough moves in from the West forming a depression along it as it dives SE over the UK with a period of potentially heavy rain and more importantly snow in the East as it runs into the cold air.

GFS then absorbs the main energy from the system South of the UK taking the rain and snow away with it leaving the UK under cold and cloudy weather on Tuesday with a gentle thaw of any lying snow especially in the North. By midweek the Atlantic makes inroads into the UK with a trough staggering East through the UK with rain preceded by a little snow in the East. From then on through to the end of the run GFS shows a much more Atlantic based pattern though not mild with further chilly winds and potential for snow developing towards the end of the run again as the block ever present to the NE strengthens again and realigns itself favourably for cold to the UK.

The GFS Ensembles show a rather cold couple of weeks to come with the 850 values averaging lower than normal for February. The operational above did spend some of the time as being one of the milder options from the pack with the Control Run particularly chilly later on. Some precipitation is to be found through the run especially in the middle of the run as it becomes a little less cold briefly.

The Jet Stream continues to flow in a Southward direction down over the UK into Southern Europe. As far as Europe is concerned the main thrust of the flow remains over well Southern latitudes throughout the reliable time this morning. Over the Atlantic the flow weakens for a time at the weekend and breaks up somewhat before repositioning somewhat further South than recently but still moving across the UK this time more from the West.

UKMO for midnight on Tuesday shows Low pressure moving away from the UK into Europe with a slack Easterly flow over all of Britain. High pressure stretches across from Northern Europe to Eastern Greenland. It would be cold with rain and snow from Monday petering out over the South to leave a cold, cloudy and raw day with some wintry showers near Eastern coasts.

GEM shows a much slacker pattern behind the Low at the weekend with rain and snow quick to depart the South on Monday. It then shows a second Low moving SE with some rain and sleet before the Atlantic begins to push the High pressure block East and gain supremacy over the UK by the end of its output.

ECM is more akin to UKMO at Day 6 moving forward to bring a new round of energy in from the West by soon after midweek, this time with more success as the parent Low holds over the North of the UK with strong winds with rain or showers with snow on hills towards the end of the run.

In Summary the cold spell still holds good this morning. All models support at least a week of cold weather with the longer term models experimenting with breaking the block to the NE down in the middle of next week. In the meantime there is ample opportunity for snowfall for many whether it's from stalling fronts towards the end of this week or the more meaningful thrust of energy SE at the end of the weekend. Thereafter, there are signs that the block will be pushed back East to allow the Atlantic to make its way over to the East of the UK with it's milder weather, though at this range this is very tentatively shown currently and is suspect to change over the coming days. With regards to snowfall as mentioned all areas are at risk of some but East and North looks best positioned and as is always the case in these situations the axis and position of the Low in it's movement SE at the weekend has little margin for error for more Southern and Western areas with cold rain a distinct possibility if the axis shifts slightly further East. This will be firmed up on over the coming days.

[Gibby]

Good morning. Here is the report of the 00z output from GFS, UKMO, GEM and ECM for today Thursday February 7th 2013.

All models show a weak front moving into the UK today and becoming slow moving at the same time as dying in situ over Western Britain tomorrow. After a cold and frosty start with still the odd wintry shower in extreme Eastern Coasts the day will steadily become cloudy with outbreaks of mostly light rain moving in from the West through the day. This may fall as snow on higher hills, especially in the North. Winds will be lighter than recently. The rain and sleet will continue overnight and into tomorrow before dying out leaving a legacy of cloud and rather benign conditions still under rather cold air. Saturday could well be a dry and brighter day with some sunshine as a ridge moves across from the West with frost possible overnight. On Sunday all models show a much more active frontal system edge in from the West with an attendant developing depression sliding down over the UK towards Southern Britain and into NW Europe over Sunday and Monday.

GFS then shows the Low close to Southeast Britain for several days in the early part of next week with cold NE winds wrapping around the feature. Sunday will become wet for many with heavy rain turning to snow over the hills later, a trend that continues over Monday and Tuesday with possibly disruptive snow in places before drier weather edges in from the NW by midweek as a strong ridge of High pressure takes control with snow being replaced by a cold and frosty spell with some daytime sunshine towards the end of next week. High pressure remains in control for some time then with further frost at night while the far North see weak troughs brushing over the top of High pressure bringing a little rain or sleet. Through FI today Low pressure regains control as Low pressure moves East across the UK bringing rain or sleet at times and further snow on the hills at times in continuing temperatures that are often below the seasonal average.

The GFS Ensembles show a rather cold picture with the operational run above being one of the milder members at times. The average for the run remains below the long term mean, at least in the South. Rainfall amounts will peak at this weekends and early next weeks Low before drier conditions take over.

The Jet Stream still flows down from the North on the Eastern flank of its ridging around the Azores anticyclone. The flow does break up at the weekend before realigning itself still blowing from a NW or North direction down over the UK around the seemingly permanent Azores High in a weeks time. The flow continues to track Eastwards at low latitudes over Southern Europe throughout the next week.

UKMO shows the weekend Low over East Anglia at midnight on Monday with a cold Northerly or NE flow developing on the Northern flank of the SE moving depression. With most areas having endured a wet and breezy Sunday rain would turn to snow as we move through the overnight period and into Monday itself as it clears steadily away SE through the day. As we then move towards midweek the weather remains cold and with a NE flow in the South especially some snow showers would be likely, especially on Tuesday before things settle down though staying cold from the NE by Wednesday.

GEM today keeps the axis of the SE moving Low further to the SW with more areas seeing significant snow as early as Sunday before it too pulls the Low away into Europe leaving a legacy of cloud and lessening wintr conditions through the early days of next week. By midweek a ridge is shown crossing from the West with unsettled, less cold but windy and wet conditions taking control over all of the UK well before next weekend.

ECM shows a disrupting trough sliding across Southern England on Sunday developing a deepening depression over the English Channel with an increasingly cold and wintry NE or East flow setting up over the UK. Most areas will see a spell of heavy rain on Sunday with the rain steadily turning to snow late in the day and overnight on Sunday. With the Low pressure similar to GFS reluctant to pull away on Tuesday further sleet and snow could cause disruption to many Southern and Eastern areas in particular before the Low finally pulls away SE over Wednesday leaving a cold and raw NE flow over the South with snow showers near the East Coast while the North becomes dry and cold with overnight frost as a ridge moves in from the NW. This ridge then holds ground over the Uk for a day or two before the close of the run sees an Atlantic front bring rain in from the West preceded by snow for upland areas with NW winds and showers following to the West. This would usher in less cold but far from mild weather.

In Summary today there is still much indecision about the path and the depth of the feature bringing the potential wintry conditions early next week. It looks increasingly likely that we will all have to endure a spell of heavy cold rain on Sunday before cold air engages the feature fully later on Sunday, overnight and into Monday turning rain to snow and potentially causing some disruption to travel on Monday, particularly if the more persistent feature clings on close to the SE like GFS and ECM suggests. UKMO and GEM bit pull the Low away quicker to the SE allowing High pressure to collapse SE over the UK before milder air attempts to regain control over the UK as the block to the NE is possibly pushed further back to the East. A week is a long time in these type of winter synoptic situations so expect some more surprises over the coming days towards or away from milder solutions.

[johnholmes]

a quick pdf guide to what the 500mb anomaly charts are, what they can and cannot do etc

500mb charts-are they a useful guide-8 feb 12.pdf

[johnholmes]

I will post the 2nd part early this evening. It uses current and recent data to predict what the upper pattern is likely to be for 6-15 days ahead

[johnholmes]

As promised here is the pdf with my analysis of the upper air charts and its implications for the UK weather 6-15 days or so on from now

500mb charts-how useful part 2-7 feb 12.pdf

[cerneman]

As promised here is the pdf with my analysis of the upper air charts and its implications for the UK weather 6-15 days or so on from now

500mb charts-how useful part 2-7 feb 12.pdf

John I am gradually learning, Thanks for your time and patience,

[fluid dynamic]

As promised here is the pdf with my analysis of the upper air charts and its implications for the UK weather 6-15 days or so on from now

500mb charts-how useful part 2-7 feb 12.pdf

excellent explanation for us learners. Thanks.