Model Output Discussion - Spring 5th March Onwards 6z--->

[Summer Sun]

GFS again shows things turning a good deal warmer from Easter Sunday as the high begins to establish its self

 

Mid teens quite widely on Sunday and Monday

 

 

By the Tuesday the north sees a slight dip in temps (still double figures) whilst most of the south hangs onto the mid teens

 

 

Onto the Wednesday and virtually all of the UK sees temperatures in double figures

 

 

And the final chart for these temps is a week Thursday and its shows mid teens widely in the south and maybe even the north west of Scotland could join in

 

 

So after a chilly feeling March some spring warmth could be on its way

 

[Winter Cold]

Morning all

 

Definately strong agreement from GEFS this morning for at least a week of high pressure domination. SLP well above 1020 for a good 7 days, with only a few straglers!

 

 

 

Temperatures also look decent with low-mid teens showing with support from the Op, control and mean - but its too early for now to be sure as its all about the high placement and cloud amounts:

 

 

 

Examples for South Yorkshire

Edited March 31, 2015 by Winter Cold

[Summer Sun]

The 06z from GFS isn't as settled as previous runs with more of an easterly flow at times best wait and see how it sits with its ens update later on, could be just the 06z 'going off on one' its happened many times before like winter cold posted above the 00z ens shows a week at least of settled weather from the 5th

[Frank Trough]

Morning all

 

Definately strong agreement from GEFS this morning for at least a week of high pressure domination. SLP well above 1020 for a good 7 days, with only a few straglers!

 

gefsslp313.jpg

 

 

Temperatures also look decent with low-mid teens showing with support from the Op, control and mean - but its too early for now to be sure as its all about the high placement and cloud amounts:

 

gefstemp313.jpg

 

 

Examples for South Yorkshire

 

the 06z op goes with the "straggler" scenario!

 

 

 

...which then sets up a horrible easterly/northeast flow across England. Next week would be pretty horrible in that scenario - cold and grey.

 

It does still deliver a decent 3 days for Easter and even good Friday isn't looking quite as bad as it was the further southwest you go.

 

Hopefully still an outlier solution - plenty of chops and changes to come beyond t+144.

Edited March 31, 2015 by Certain kind of fool

[Frosty.]

The Easter weekend is actually looking ok, it will become dry, winds will become light, there will be a fair amount of cloud, initially at least but there will also be sunny spells and in the sunshine it will feel pleasant but cold nights where skies clear. The GEFS 00z mean is a beauty, it shows high pressure building in over the top of the UK, intensifying and lasting for anything up to two weeks, once the high is established, I think changes will be very slow.

Edited March 31, 2015 by Frosty.

[Summer Sun]

As expected GFS 06z was an outlier with its ens going for high pressure over the UK similar to previous runs with light winds and some sunshine it will be feeling warmer though still cold over night where skies are clear

 

Op

 

 

Ens

 

 

The met office are on board now as well suggesting the high will last till mid April

Edited March 31, 2015 by Summer Sun

[legritter]

The Easter weekend is actually looking ok, it will become dry, winds will become light, there will be a fair amount of cloud, initially at least but there will also be sunny spells and in the sunshine it will feel pleasant but cold nights where skies clear. The GEFS 00z mean is a beauty, it shows high pressure building in over the top of the UK, intensifying and lasting for anything up to two weeks, once the high is established, I think changes will be very slow.

Yes looking at todays output charts i would say some very pleasant weather could be around the corner .

But under scrutiny just a few tweaks here and there could mean the difference between High pressure dominance or the uk  on the wrong side with low pressure battling it out over or near the UK .A few more runs needed but atleast we have some interesting possibilitys and certainly not a Bore fest ,something to keep us all interested /  

[Frosty.]

The GEFS 06z mean looks fantastic between Easter and mid April with a strengthening anticyclone over the UK bringing fine and dry conditions with long sunny spells and light winds, temperatures recover to average and then slightly above by day, I'm thinking mid teens Celsius and nearer high teens in prolonged sunshine but cold nights where skies clear. The met office update today is an upgrade on the duration of the anticyclone which now lasts into the middle of April, at least across the southern half of the UK.

[knocker]

The latest EC32 has HP in charge until around the 17th and then back to zonal with LP to NW/N and HP to SW. Temps varying around the norm.

[Frank Trough]

looking at the 06z ensembles there is more support compared to the 00z for more unsettled weather post easter with the trough sinking south - the control is similar to the op:

 

 

 

naturally the mean looks better, diluted by the other perturbations. I'm not holding my breath anything prolonged and spring like for the south just yet, but hopefully this is painting the worst case scenario which will ameliorate as it gets nearer to T +0 and in fairness the control does improve quite quickly.

 

Until this morning the ECM has had the high pressure slightly further northwest giving a colder flow (although the little trough drops further east) although it's quite different synoptically from the GFS in the placement of the high:

 

 

 

However, i'm glad the METO are suggesting settled weather and warmer days so for now i'm hoping that's the call.

Edited March 31, 2015 by Certain kind of fool

[Frosty.]

The Gfs 12z shows an improving Easter weekend as high pressure builds in with Sunday and Monday being the sunniest and warmest days with mid teens celsius and light winds. Then there are changes, the high drifts northwest which allows much colder air to spread from the northeast but the latest met office outlook sounds much nicer. The placement of the high next week is going to make the world of difference in terms of surface conditions as this run shows beyond T+168.

[mushymanrob]

Gfs looks to be an outlier... It has no support from the noaa anoms, .

[Winter Cold]

Gfs looks to be an outlier... It has no support from the noaa anoms, .

 

Its certainly one of the worst case scenarios beyond next wednesday, and goes onto be an outlier after next weekend. The mean and control are more inline with the 0z GEFS I posted this morning

 

Heres the 12z GEFS:

 

 

 

Having said that, the ECM and GFS seem have done a swap on their operational runs this evening with the GFS now holding the high out west and ECM moving it further east than its earlier runs. They really try your patience sometimes dont they!

[Frosty.]

Good news from the GEFS 12z mean, the high drifts slowly east next week, it's nothing like the op which showed the high drifting away northwest. Next week looks fine and dry with light winds and temperatures recovering to average and then slightly above by day but still a risk of night frosts, I think there will be lots of sparkling spring sunshine during next week and further out to mid April.

Edited March 31, 2015 by Frosty.

[Man With Beard]

Evening all. I note a consistent trend to place a trough to the west of Iberia after Easter. This is a classic trigger of a warm spell, as a persistent UK high could eventually set up and then get held in place by the "Azores Low". Could of course result in retrogression or overrunning of the pattern by a strong jet, so I'd say 40/60 chance of it happening at this stage, but if it does, a run of days maxing above 20C by the weekend after next would be likely.

[Frosty.]

Tonight's Ecm 12z will please many on here, much better than the Gfs run. The UK based high intensifies next week and migrates slowly east with winds eventually becoming southerly, this turns into a very nice run.

[I remember Atlantic 252]

Tonight's Ecm 12z will please many on here, much better than the Gfs run. The UK based high intensifies next week and migrates slowly east with winds eventually becoming southerly, this turns into a very nice run.

 

Thats the spirit Frosty!, ready for spring now, I do not want lousy NW'lys here at low level south

[Summer Sun]

Tonight's ECM ens remains in line with previous updates with the high building through the weekend and lasting well into next week

 

 

Temperatures will be around or just below average at first but if we can start and get some longer periods of sunshine next week it will start and feel warmer

[BlueHedgehog074]

Tonight's NOAA (6 to 10 day and the 8 to 14 day) and the 8 to 10 day GFS/ECMWF 500mb anomaly charts do seem to keep higher than average heights over the UK. The 500mb flow on the anomaly charts (green lines on the NOAA charts and the green/blue/black lines on the GFS/ECMWF mean chart) also carve out a ridge of High Pressure building North and North-Eastwards over us. So certainly some quite good confidence that the Atlantic and it's unsettled Westerly driven weather could be going for a sleep in its bed away from the UK. Signs on the charts for a trough of low heights to develop to our West with some of this penetrating towards the Western Spain area. I think I remember someone once saying that troughing in the Atlantic digging far enough South can help force heights to build North/North-Eastwards over the UK and to our East/North-East. As such, I guess it's not too much of a surprise to see the anomaly charts demonstrate this sort of scenario. Probably nothing especially warm or cold, and the charts would suggest the weather probably being mostly calm and settled. But maybe a possibility that a warm Southerly/South-Easterly drift could be picked up from the High Pressure system's Western flank should it manage to get far enough to our North-East. (this being especially true on the GFS's 8 to 10 day mean chart, where it has a 500mb flow from the South over Western UK).

I think as some have said, not really much support for this fella (GFS 12Z) - charts above not pointing to any blocking to our North-West. Will admit, though, this would have been quite a mouth drooling chart for some of those who like the cold and snowy conditions if it happened a little bit earlier.

(I suppose a few days Northerly or North-Easterly originating from the Arctic and/or a Northerly followed by some kind of Channel Low/Western UK Low bumping into the cold air over the British Isles could provide some last resorts for widespread wintry weather for anyone still wanting to see one or two last cold shots).

The way the weather seems to be going for the time being, does look possible that High Pressure will be booking some holidays over the UK in the next few days or so. This of which then possibly drifting a little further North or East. But still quite likely it will remain influential over the British Isles with some of the wet and windy weather that's invaded places in these last few days (with a bit more to come) getting stamped-out. As usual, the weather can still easily change in the 8 to 14 day period, but do kinda feel there's enough evidence, particularly from the mean and anomaly charts, to suggest that there won't be much in the way of wild weather within the next week or two.

[jamie82]

I for one hope that the 18z is on one as I don't really fancy being in Egypt next week with those kind of temperatures.

[Eugene]

Getting rather tiring to read anything not supporting warm and dry an outlier, GFS 18Z isn't exactly warm next week, as damian said the other day April is when you are likely to see northerly blocking, nice pleasant weather with temps around average looks the most likely.

[knocker]

Everyone is aware that the orientation of the HP this weekend is quite important. This morning's GFS confuses the issue slightly by introducing a small perturbation running down the North Sea Sunday morning before settling the HP in the wrong place leading to quite cool conditions on Monday.

Charts weatherbell

[IDO]

Getting rather tiring to read anything not supporting warm and dry an outlier, GFS 18Z isn't exactly warm next week, as damian said the other day April is when you are likely to see northerly blocking, nice pleasant weather with temps around average looks the most likely.

 

The problem with the GFS op since its upgrade is that any opportunity to send a HLB into the mix it will do. This winter and spring it has popped one up on a regular basis but they have not materialised. The mean is a much better bet after D7. The late stages of the London Graph highlight it has no support comparing the 850hPa and 500 temps:

 

 

As Knocker says possibly a little feature on Sunday. One to watch, little support at the moment but the op is usually first to spot such a mesoscale change. At the moment it dumps its load in the North Sea so eastern coasts may be at risk of some drizzle:

 

 

 

GEM does not have that, and is HP dominated from D4 till D10 but is a mobile features and I am sure that will change over the next few days:

 

 

 

ECM differs again but basically HP from D4-10: 

 

The D12 clusters suggest the HP will migrate east and it is looking like around D14 the pattern becomes less certain with HP remaining the biggest clustering but lower pressure showing up in more members, early days yet though:

 

D12 clusters: 

 

In the nearer term the WRF hi-res also has the front crossing the UK on Friday and again they indicate the south will miss the worse of it but some heavier stuff for parts of the UK:

 

Next 8 days totals: 

 

So Friday looks to be the worse day, though the front clears the east coast by midday, though showers following, but in the SE temps could recover to average on Friday afternoon. The rest of the Easter looks dry but neither cool or warm IMBY.

[Gibby]

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 08:00 ON WEDNESDAY APRIL 1ST 2015.

 

THE CURRENT GENERAL SITUATION A chilly NW flow will weaken further today as a wave feature moves SE over SW Britain later today and followed by a warm front moving NE over the same areas tomorrow.

 

http://www.wetterzentrale.de/pics/Rtavn001.gif 

 

MODELS-2 WEEK HEADLINE Becoming settled and dry with some sunshine and average temperatures but with a risk of occasional night frosts.

 

THE GFS JET STREAM ENSEMBLE FORECAST The Jet Stream forecast indiciates the current West to East flow across the UK is weakening and returning to a more northerly latitude near iceland as pressure builds across the UK this weekend. Later in the period the flow looks like splitting with the most energy fuelling the southern arm near Spain and Portugal as pressure builds to the North and NE of the UK.

 

http://www.netweather.tv/index.cgi?action=jetstream 

 

GFS OPERATIONAL The GFS Operational this morning shows the current unsettled, windy and changeable period of weather coming to an end over Easter as High pressure is shown to build strongly across the UK. Whilst mostly a cloudy High to begin with brighter conditions will develop with time and temperatures should recover to average in light winds but with the risk of night frosts. This pattern then persists through Week 2 with all eyes to the East on how colder incursions over there  threaten the South of the UK in the generally dry and settled pattern right out to the end of week 2.

 

http://www.wetterzentrale.de/pics/Rtavn1441.gif

 

http://www.wetterzentrale.de/pics/Rtavn3841.gif 

 

THE GFS CONTROL The GFS Control Run also shows only small variations on the theme set out by the operational with fine and settled weather looking most likely in the High pressure based outlook, the centre gradually transposing North towards the latter stages and perhaps allowing something a little more unsettled to creep towards the SW of Britain late in the period.

 

THE GFS CLUSTERS  The GFS clusters today for two weeks time show a 50% group indicating that High pressure is likely to lie across the UK at that time. The other 50% are made up of unclear positions mostly revolving around High pressure much further to the South or SW and Atlantic fronts and depressions to the West and North having a more direct influence across the UK..

 

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

 

UKMO UKMO today shows pressure building across the UK over Easter with the centre then settling just to the SW of Britain early next week with a rather cloudy NW flow likely to establish across the UK.

 

http://www.wetterzentrale.de/pics/Rukm1441.gif 

 

THE FAX CHARTS The Fax Charts show rising pressure across the UK in the coming 4 days or so not before a complex system of troughs moving East and then decaying in situ leave a residue amount of cloud and mistiness over the UK for much of the weekend.

 

http://www.weathercharts.org/ukmomslp.htm#t120.

 

GEM GEM today looks a lot like UKMO in the 4-6 day range as the High over the UK lies to the SW in a NW flow before stretching it's influence further and further North later next week cutting off the rather cloudy NW'ly but maintaining dry weather for all in a chilly Easterly flow across the South later.

 

http://www.wetterzentrale.de/pics/Rgem2401.gif 

 

NAVGEM NAVGEM has High pressure developing further North much earlier placing the South of the UK in a very chilly East flow next week with the risk of showers in the SE looking possible while all other stay fine and dry but not overly warm with frosty nights..

 

http://www.wetterzentrale.de/pics/Rnvg1681.gif.

 

ECM ECM is much more friendly in the positioning of the HIgh in that it wards off any Easterly input by placing the High over the UK before drifting it slowly East to give rise to a more SSE feed later. There is an equal amount of dry weather shown as with the other models but hopefully temperatures would be rather higher.

 

http://www.wetterzentrale.de/pics/Recm2401.gif

 

ECM 10 DAY MEAN(12z) The ECM 10 Day Mean Chart shows High pressure well in control of the UK weather in 10 days with a centre close to or over the UK.

 

http://www.wetterzentrale.de/pics/Reem2401.gif 

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models continue to show a trend towards High pressure based conditions from around Easter lasting through most if not all of Week 2.  

 

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKM & ECM The current verification statistics for the past 31 days shows ECM leading the way at 3 days with 97.8 pts followed by UKM at 97.5 pts and GFS at 96.7. At 5 days ECM  continues to lead the field at 91.2 pts over UKMO at 90.6 pts and GFS at 88.1. At 8 days ECM remains the leader with 68.4 pts over GFS's 64.5 pts. Then at Day 10 ECM retains superiority at 48.5 pts over GFS at 46.6. 

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png 

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.prig

 

 

MY THOUGHTS The main talking point between the models is the continuing undecisiveness in where High pressure will lie then drift once formed over the Easter weekend. It looks almost certain that High pressure will be the driving force of the UK weather over the coming two weeks with certainty that it will form over the UK over Easter. Then it looks far less certain where it will move after that which dependant on where it eventually sits becomes instrumental as to what type of High pressure based weather occurs in any one region or place. There is a bias towards moving High pressure further North later which introduces at least a risk of chilly Easterly winds affecting the South at times later continuing to temper temperatures. GFS, GEM and NAVGEM all like this placement this morning although the GFS Clusters aren't particularly supportive of this scenario. ECM is much kinder with it's positioning of the High just to the East of the UK in 10 days which could be more supportive of better temperatures if nothing else. So what can we expect weatherwise from all this over the next few weeks. Well the main thing is that there will be very little rain after the next 48 hours or so anywhere with dry weather being the most guaranteed parameter. However, sunshine amounts and temperatures are much more problemmatical as in the first stages taking us through Easter and the start of next week a lot of cloud could be present for many and any feed from Europe later could also prolong this factor as well as draw even chillier air West over us but if the High drifts to the East and allows a more Southerly or SE drift such as ECM suggests then things could soon become warmer and more Springlike. So in a nutshell this morning we can look forward to dry and settled weather for a week or two but with no early heatwave as it stands at the moment. It looks like we will be chasing holes in the cloud for some Spring warmth at times though but in all honesty the outlook could look far worse.    

 

Issued at 08:00 Wednesday April 1st 2015

[stodge]

Morning all

 

I'm far from convinced we've even got the detail for the coming weekend sorted. The earlier meme of a fine, warm Easter seems to have been consistently downgraded over the past few days.

 

This morning's GFS 00Z OP, which seems to be canned by the usual suspects on an almost daily basis, is strongly anticyclonic though for those looking for warmth, profoundly frustrating.

 

http://modeles.meteociel.fr/modeles/gfs/runs/2015040100/gfs-0-120.png?0?0

 

Not terribly warm

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015040100/ECM1-120.GIF

 

Better though not really a heatwave but would be pleasant enough for all.

 

http://modeles.meteociel.fr/modeles/gem/runs/2015040100/gem-0-120.png?00

 

GEM different again - so a long way to go yet before we can be confident beyond Friday which doesn't look too promising it has to be said.

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.obs.gif

 

As of yesterday, the AO coming off its current high number

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.sprd2.gif

 

Looking ahead, a sharp fall back to neutrality as perhaps once again we try to get the set up of heights over the Pole and LP further south but huge scatter into the medium and longer term periods so lots of options on the table. EC32 apparently suggests the return of the Atlantic but that's default so I remain to be convinced. The emphasis for HLB seems to have shifted back to Scandinavia from Greenland in the last few days but that might just be indicative of no strong signal into mid-month. GFS has toyed with any number of HLB and MLB scenarios into FI so we'll see...

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao.sprd2.gif

 

The NAO is starting to catch my eye - it's been as positive now as it's been all winter but the signs are for at the least a return to neutrality and quite a cluster of members going negative and, apart from a brief period at Christmas, the NAO has been positive for ages.

 

http://modeles.meteociel.fr/modeles/gfs/archives/gfsnh-2014122500-0-6.png?0

 

This is the last time the NAO went negative - Christmas Day in fact. The key, I think, is the large LP in mid-Atlantic which would depress the pressure anomaly for that region. Going forward, a negative NAO in April might suggest a deep LP in mid-Atlantic throwing HP north or east ahead of it and I wonder if that's where we might be in mid-April with the Atlantic dominated by a static deep LP and strong HP over NW and NE Europe ahead of it.