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

[mushymanrob]

The anomaly charts continue to show a flow from somewhere north of west not from the east, although GFS this morning does show a hint of an upper ridge in that area. NOAA last evening supported the north of west upper flow with heights shown to be about 552-555DM from the Gt Lakes area. So no major warmth but the odd day with any surface ridging in the right place could make for a pleasant day. Overall temperatures would be at or a bit below average. So hill snow for Scotland and the northern hills of England at times rather than beach weather! That is for the 6-15 day time scale, so the rest of March really.

 

indeed, which is why im not buying the gfs's scandinavian high/cold easterly no matter how often one is suggested. we have seen that when the noaa anomaly charts and the gfs clash in that timeframe, the gfs is nearly always wrong.

[Polar Maritime]

Some pretty chilly charts showing into the runs from both GFS and ECMWF. With an unsettled cool sometimes cold N/W flow influencing the end of March.

 

Edited March 18, 2015 by Polar Maritime

[ANYWEATHER]

Not a lot of weather to talk about ,but we may get an active convective day around next Tuesday T+144 hrs  a long way off, but if this verifies ,an unstable, cold atmosphere, along with some strong spring sunshine should make for at least some photogenic skies and some tall clouds......Keeping an eye on this one!

[damianslaw]

A fairly changeable theme is what the models are showing, nothing especially mild nor particularly cold with temps on balance averaging out very near normal though there will be swings with some colder air at times especially for the north as we move through the rest of the month. Quite a dry outlook as well particularly in the south, with frontal activity programmed to be quite weak again away from the north.

 

The weekend  should be fairly quiet but cool before an atlantic front moves down from the NW and we usher in quite a cold flow early next week, becoming milder mid week with more of a westerly flow. However, GFS is toying with a colder outlook generally with heights building to the NE again.

 

Despite not much to startle anyone - the outlook isn't without interest with varied conditions from day to day all very seasonal. Spring has started on a much more traditional note this year than last for instance the anomalous warmth ushered in a very early start, this year it only really feels it is getting a move on now, some 3 weeks or so later than last year.

[IDO]

The GFS op is again garnering nominal support amongst its ensembles and is very progressive with the Atlantic push after D10. The pressure graph highlights this:

D13 is an example of this but any day after D11 would be similar:

op: Control Mean:

The difference in the latitude of the jet in the great scheme of things is small so down to luck whether the south can get some warmer settled weather as we head into late March. As for the temps, the uppers mean looks to be around or just above the seasonal average so I am not seeing a particular cold upper flow:

Sums it up really, just normal March weather, no sustained cold or warmth. Ignoring the unlikely op, rainfall still looks below average from next week (dry for the next four days in the south).

Not looking promising for cloud cover for the eclipse tomorrow morning in the SE though other areas more hopeful:

Edited March 19, 2015 by IDO

[Frosty.]

The Gfs 0z op shows a change to unsettled weather through the second half of next week with an increase of vigorous depressions on a collision course with the UK. Next Monday shows a narrow band of rain pushing southeast but I've noticed it has been delayed compared to earlier runs and it breaks up and never reaches the south, indeed, southern UK looks fine and mild on Monday but Tuesday looks colder with winds coming down from the north and showers are likely to break out quite widely, some with hail and thunder with snow over northern hills. Midweek sees a brief pressure rise from the west but the trend is for high pressure to decline southward allowing much more unsettled Atlantic weather to take control, some very wet and windy spells in the run up to Easter.

[Gibby]

Good morning. Firstly apologies for those attempting to access my website. The Server is down currently from my Servers end and I'm not sure when the service is resumed. Not happy. Meanwhile I will do the daily analysis direct from this forum today,

 

The Current Analysis. A slack air pressure gradient exists across the UK as High pressure continues to dominate. Through tomorrow a weakening front moves slowly South across Northern Britain.

 

The 2 Week Weather Headline. Fairly quiet Spring weather with just a little rain between lengthy dry and bright periods. Perhaps more genrally unsettled and windy in the North later.

 

GFS Jet Stream Forecast. The Jet Stream is aligned SW to NE to the NW of the UK before truning South down over the UK or the North Sea over the coming days. Through next week the flow gradually becomes somewhat stronger and eventually sets up on a West to East course across the UK through the second week as surface winds strengthen in association with Low pressure to the North.

 

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

 

GFS Clusters. The GFS clusters show a lot of variations on a High pressure based outlook this morning but with a 40% share indicating a much more mobile West or NW flow with rain or showers at times with High pressure much further to the SW of 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=

 

The GFS Operational The GFS Operational shows quite changeable conditions across the UK over the coming two weeks but with only a gradual decline into conditions unsettled enough to give much in the way of rain, especially in the South. The basic premise is for High pressure to lie down to the SW with Atlantic troughs crossing East over the North of the UK and then SE over Europe, each giving it's own version of rain followed by chilly weather with some showers, wintry on the hills. Even by the end of the run there is still a lot of dry weather shown near the South as High pressure remains not far from the South of England.

 

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

 

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

 

The GFS Control Run is not dissimilar with the same changeable pattern illustrated throughout the two week period today and also showing High pressure down to the SW of the UK deflecting the worst of the cloud and rain away to the North of the UK with a lot of benign Westerly winds across the South with a lot of cloud but not much in the way of rain.

 

UKMO today shows a front moving South early next week with some rain introducing some cold and unstable and likely showery air midweek with some wintry showers on high ground almost anywhere during the afternoons and a strong chance of frosts at night.

 

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

 

The Fax Charts today show a weak front crssing slowly South tomorrow and followed by High pressure again for many over the weekend in chilly air. A further front is shown to move South early next week, rather more active than it's predecessor with some rain for all for a time.

 

http://www.weathercharts.org/ukmomslp.htm#t24

 

GEM this morning shows three weather types this morning over the next 10 days. In the next few days a lot of dry and benign weather will ensue with a lot of cloud but only a little rain from a trough from the NW from tomorrow. Then a few dry days are followed by the second phase when a cold North or NW breeze carries wintry showers down over parts of the UK towards the middle of next week before the final pahse sees increasing Westerly winds and more unsettled weather, especially in the North under average temperatures by then.

 

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

 

NAVGEM looks very similar in sequence of events towards the middle of next week with a little rain for all on the cold front moving South. The model and front then introduce a cold and unstable pattern across the UK a week from now with some rain in cold air and wintry showers as a result in places.

 

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

 

ECM today has moderated it's tone in respect of the passage of the cold weather shown by some other output towards the middle of next week. The cold air just takes a glancing blow at Eastern Britain with a day or so of the risk of a wintry shower before the return of a strong Atlantic Westerly wind drives milder and more changeable conditions across the UK late in the run with rain at times with strong winds in the North.

 

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

 

ECM 10 Day Mean Charts. The ECM 10 Day Mean Chart remains largely unchanged from yesterday morning with High pressure near the Azores and Low pressure well to the NW with a broad Westerly flow with rain at times in average temperatures, most of the rain over the North and West.

 

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

 

Trend Changes From Previous Days are generally much in the same vein as was shown yesterday but with less impact from the Euros on the Northerly midweek next week and the extent South of the later changeable weather shown by all models watered down somewhat again today in respect to Southern Britain.

 

MY THOUGHTS The pattern this morning has basically changed little over the last 24 hours. For a time it looked like we could have a couple of very showery days next week under a cold Northerly which could of given daytime wintry showers to many and frost at night. This morning this theory has been watered down as the axis of the Northerly is further to the East and quickly replaced by a ridge of High pressure and the strengthening Westerly flow that all models seem to indicate likely through the second week. With all this tooing and froing of how much influence fronts and Low pressure have over any one place is dependant on where in the UK you live. As has been the case all Winter the same scenario is still influencing the UK weather in that High pressure down to the SW is still proving strong enough to ward off any full blooded attack of Atlantic Westeries and attendant rain or showers at least from the South while the North may see more appreciable rain and showers later in the period while the South see little more than occasional rain mixed in with longer drier if rather cloudy skies. With winds from a West or NW point for the most part temperatures will be unspectacular but never particularly cold with some warm sunny breaks at times though overall temperatures will be no more than average or just a little below for much of the time.

[Frosty.]

The Ecm 0z op also shows a change next week from the current very benign conditions to something more Atlantic driven but the main thrust of the unsettled spell later next week onwards is across Scotland whereas the south is closer to high pressure centred to the southwest and has more in the way of fine and mild weather.

[Frosty.]

Good news from the GEFS 00z mean, especially with the Easter holidays fast approaching, the mean shows the Azores high building in again so it could be a settled and mild Easter. Looking at next week, the north gradually turns unsettled from the west but southern Britain looks better with influence from the anticyclone centred to the southwest of the BI.

[Frosty.]

The difference between the Ecm and Gefs 00z mean is the alignment of the jet, the gefs is more sw / ne whereas the ecm is more nw / se but in terms of surface conditions it's similar. I think we are going to start reading the words north / south split to describe the overall weather pattern during the next few weeks with northern Britain trending predominantly unsettled whereas southern areas become changeable but with the balance tilted in favour of mainly dry and bright, pleasant conditions.

[tinybill]

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=6

 

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

 

morning  all i got  a  rare  day  off   to-day just been looking at  the  charts things are looking after  march 26  very  unsettled at the  moment

[Frosty.]

Inland convection is going to produce exciting weather next Tuesday with the UK under a polar airmass and after a sunny start, clouds start to bubble up with widespread showers breaking out, many of them heavy with hail and thunder, it will also be cold enough for snow on northern hills. Tuesday night looks clear and frosty as pressure builds from the west with midweek mainly dry with sunny spells and just a low risk of a shower in the east. Beyond midweek, the 6z shows the weather becoming more unsettled across the north and occasionally the ebb and flow of the polar front jet draws the unsettled weather into the south but although the signal from around T+168 onwards is for high pressure to decline southwards allowing the Atlantic to dominate, it appears as though the south of the UK will have the best of the conditions during the next few weeks due to high pressure to the southwest of the uk, occasionally unsettled further south but with lots of fine and dry weather too...Looking forward to next Tuesdays showers fest.

Edited March 19, 2015 by Frosty.

[IDO]

Despite the pessimism of an Atlantic onslaught from the GFS op after D10, even on the 06z run, the GEFS mean and the control continues with a N/S split:

 

 

 

This ties in nicely with the updated JMA week 2 anomaly:  w3-4: 

 

The week 3-4 is also keen on the Azores maintaining a theme for the UK. How far north or south the jet flies yet to be determined. However no clear signal for a zonal pattern or any late cold.

 

 

[Frosty.]

The GEFS 06z mean shows a north / south split post T+168 with Azores high influence extending into the south through late March but always more unsettled / Atlantic driven across northern Britain but looking further ahead, Easter looks pleasant and settled thanks to the Azores high. I hope this is a sign of things to come during late spring and throughout the summer.

[Summer Sun]

The ensembles of GFS and ECM from the 28th March to 2nd April both paint a completely different picture - GFS shows high pressure having more of an influence whilst ECM has a north westerly flow

 

 

charts WSI euro weather

[Summer Sun]

Big differences at t144 this afternoon from GFS and UKMO

 

UKMO shows an easterly flow bringing lots of cloud and suppressed temps with some drizzle possible

 

 

GFS on the other hand is more inline with the met offices outlook for next week with high pressure mid week allowing some brighter conditions to develop though temperatures are likely to be below average for just about all

 

Edited March 19, 2015 by Summer Sun

[Frosty.]

There could be some very active weather next Tuesday according to GFS 12z, heavy showers with hail and a risk of thunderstorms, especially across eastern England.

Watching big showers forming is one of the things I look forward to in spring once inland convection becomes strong enough.

[Frosty.]

The Gfs 12z is a decent run for the southern half of the UK with the Azores high ridging NE and pushing the polar front jet further north and for most of England and Wales, plenty of fine and pleasant weather with temperatures into the low to mid teens Celsius, very nice spring weather on this run.

[Frosty.]

These charts from this evenings Ecm 12z are not bad for the south, plenty of fine and increasingly mild although sometimes breezy weather post T+168 with most of the unsettled and windy weather hitting Scotland and even the north looks occasionally fair. I think the Azores high could play a big part in our weather during easter..at least for England and Wales

Edited March 19, 2015 by Frosty.

[Cloud 10]

There's something familiar about the day 10 ensemble mean from the ECM tonight...

 

 

 

......Aha!

 

[Frosty.]

GEFS 12z mean trend is good with high pressure gradually building in from the southwest as we approach the Easter period. We could be looking at a settled and pleasant spell by the end of March or early April with temperatures around the mid teens celsius.

[knocker]

The general theme of the latest EC32 anomalies.

 

By T240 the ridge to the SW of the UK replaced and pushed south by LP Canada and Iceland Thus a low pressure north of the UK bringing NW Pm and unsettled weather to most of the UK.

 

By T408 LP still  LP Greenland with the ridge to SW possibly influencing the south but still the surface LP to NW and N bringing NW/W  unstable airstream.

 

By T578 still weakening signs of Canadian vortex (bearing in mind the range) but pressure rising over the Pole and the Azores ridge taking more of a grip so perhaps more settled weather on the whole for the UK.

 

By the end of the run nothing sticks out but tending towards rising heights Greenland and LP western Atlantic so the flow more SW over the UK

 

So there wouldn't appear to be any sign of any HP domination and temps pretty much around average.

[mushymanrob]

GEFS 12z mean trend is good with high pressure gradually building in from the southwest as we approach the Easter period. We could be looking at a settled and pleasant spell by the end of March or early April with temperatures around the mid teens celsius.

 

....and the good news is that the noaa chart supports the mean...

 

but first we have a rather messy week ahead with more cloudy cool weather, cold even at times.

[IDO]

The general theme of the latest EC32 anomalies.

 

By T240 the ridge to the SW of the UK replaced and pushed south by LP Canada and Iceland Thus a low pressure north of the UK bringing NW Pm and unsettled weather to most of the UK.

 

By T408 LP still  LP Greenland with the ridge to SW possibly influencing the south but still the surface LP to NW and N bringing NW/W  unstable airstream.

 

By T578 still weakening signs of Canadian vortex (bearing in mind the range) but pressure rising over the Pole and the Azores ridge taking more of a grip so perhaps more settled weather on the whole for the UK.

 

By the end of the run nothing sticks out but tending towards rising heights Greenland and LP western Atlantic so the flow more SW over the UK

 

So there wouldn't appear to be any sign of any HP domination and temps pretty much around average.

 

 

Boo!

 

Yes the GEFS mean has been trying to edge the Azores ridge in during FI. However it remains zonal for most of the UK with the jet stubbornly too close to the UK. The D12 & D14 means:

 

 

 

I would like to believe the ECM D9 and D10 charts but knowing their bias I can't run with that at the moment:

 

 

 

I suspect GEM and GFS at D10 may be closer to the mark:

 

 

 

A few more dry days for the south upcoming, then as Frosty suggests a day or two of showers in a cold 500hpa/850hpa  flow with the wind from the NW/N:

 

 

Temps recovering  to average by the end of next week with  a return to an Atlantic driven flow of lows and fronts; that is according to the gFS op and GEM:

 

[Polar Maritime]

Yes a chilly week ahead with a slack Northerly giving over night frosts, Before the Atlantic makes inroads from the N/W by the end of the week.