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

[Milhouse]

Looking at the next 8/9 days the gfs 6z has plenty of pleasant springlike conditions on offer. The next proper 'nice' feeling day looks to be Tuesday where winds are set to fall light and slightly warmer air is set to drift northwards from off the continent. Right out to the weekend high pressure is resident over the UK bringing a mix of cooler cloudy days and pleasantly warm sunny ones as a result of the different airmasses under high pressure. Out at t+240 the Atlantic fires up but most places should get a taste of spring next week.

[Frosty.]

The 6z shows a change to more pleasant springlike conditions once we lose the influence of the scandi high and replace it with the Azores / UK based high pressure, by next Wednesday it's much milder in the south compared to earlier in the week. The 6z shows variable often large amounts of cloud but with a tendency for more in the way of sunshine as time goes on as the high slowly transfers further east across southern Britain with Saturday looking the best day as by Sunday the high is being pushed further south by lowering heights further north by northwest, this process continues through low res as the northern arm of the jet strengthens bringing a progressively more unsettled pattern to all parts of the UK but later next week we are likely to have a window of fine and pleasant conditions but with cold nights.

Edited March 14, 2015 by Frosty.

[Captain Shortwave]

Mmm not too sure this will happen, the longer term general trend is cool and unsettled possibly cold and unsettled due to developments over the Poles, heights generally rising to the NW will prevent any sustained settled period - but we shall see. Both ECM and GFS show heights eroded by lower heights from the NW in around 8-10 days time..

There seems to be a small window where heights could build to our north west, but by the looks of it the vortex segment over Siberia will tend to shift back towards Canada and Greenland at around day 8/9 onwards. Things look unsettled into week 2 as a westerly pattern re-establishes.

Day 10 means

GFS

ECM

 

So a case of the mid range where we could get a cold shot (ECM op), but we are dealing with two connected high pressure cells (The Azores high and the extended ridge over Greenland). If the Azores ridge influences our weather then we won't see any cold air pushing down into western Europe. At least from Tuesday onwards we will lose the chilly and rather cloudy easterly flow. 

[Winter Cold]

Its still not too late to see a bit of snow, and if these ECM charts keep showing up then maybe some of us will! Some good posts above talking about the PV on the move and these types of charts are certainly plausable. Ill be following the progress on a cold shot anyway

 

     

[Frosty.]

The GEFS 06z mean shows a big improvement once we lose the scandi high influence and gain the Azores ridge / UK based high by next tues / wed through to the end of next week with increasing amounts of sunshine and temperatures recovering closer to average but with cold nights. Looking further ahead the trend is for progressively more unsettled weather spreading down from the north.

Edited March 14, 2015 by Frosty.

[Captain Shortwave]

No real sign of the cold ECM solution gathering pace so far

GFS

Light north easterly in southern and eastern areas, but it is a chilly surface wind off the north sea rather than a truly cold set up.

 

UKMO

Similar really

 

The issue is neither model establishes a cross polar ridge like the ECM between Alaska and Greenland which means the cold air cannot push towards the UK.

Apart from some patchy rain or showers the coming week looks fairly dry if rather cool at times, though this will ease by the middle of the week.

[Summer Sun]

Amongst the settled runs GEM takes a different route much more unsettled with another easterly setting up dragging in some chilly air though not as cold as say a month or two back

 

[Frosty.]

This looks good from gfs 12z, lots of settled pleasant weather from next midweek onwards, especially for the southern half of the UK. :-)

[Summer Sun]

Its UKMO and GFS v ECM on the position of the high on Friday

 

UKMO and GFS have it over the UK allowing some sunny spells and temperatures around 9 to 12c

 

 

ECM though has the high further west allowing some cooler air to filter down

 

Edited March 14, 2015 by Summer Sun

[Frosty.]

Those looking for fine pleasant weather will like the GEFS 12z mean which shows the Azores high ridging NE into the UK once the scandi high is out of the way, gradually becoming milder with increasing amounts of strong mid to late March sunshine and lighter winds but with chilly nights, it doesn't turn unsettled until the middle of week 2 so there is potential for a decent window of nice springlike weather, especially further south.

Edited March 14, 2015 by Frosty.

[Frosty.]

The Ecm 12z brings a brief arctic blast at the end of next week with widespread sharp frosts and snow showers to the eastern side of the UK and from there it becomes very unsettled with generally below average temperatures and strong winds at times with spells of rain and showers which would be wintry on hills and to low levels at times, FI is set up for reloads of polar and further arctic maritime air.

Edited March 14, 2015 by Frosty.

[KyleHenry]

Personally speaking I need to see one more run from UKMO in the morning just to see how much cold pooling is left on the 500 hPa level around Newfoundland region and what low pressure systems can spawn from it.

It will hopefully clear any doubts by showing slight HP rises Greenland or showing none.

I'm not dissing the GFS, there is one little niggle I have and it's how it is in tow with the ECMWF at the 10 hPa level and to where the PV locates to.

But there is a small disconnect in its 500 hPa outcomes/ knock on effects with the ECM from the final warming Strat wave.

So UKMO at 144z tomorrow morning for me is the decider.

[Winter Cold]

Great to see the ECM remain in the cold camp tonight but it is isolated really, and has no support from the other models. Still, its always lovely to see the UK bathed in deep blue

 

A few examples:

 

  

 

 

Nothing mild showing anyway, and infact the GFS run was far too mild for most of it, and mildest at one point as shown below. Temps no better than 10C id have thought for the rest of the month in Sheffield, and a few degrees cooler than that for most of the ensembles and mean:

 

[stodge]

Evening all

 

Still a huge amount of uncertainty going forward - GFS 12Z Op has a fairly flat pattern but both ECM and particularly GEM offering something much more interesting synoptically.

 

The AO has fallen back toward neutrality after last weekend's very high numbers:

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index.html

 

Looking forward and all AO members going negative next week as you might expect:

 

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

 

The rebound is swift but a huge variation between continued slight negativity and some stronger positivity suggesting the GFS option of a return to zonal conditions is an option but so is the option of maintaining higher heights at higher latitudes as suggested by ECM and GEM and both options are on the table and have support at this time.

 

The NAO remains (with the exception of one member) weakly positive between 0 and +1.5 so nothing remarkable there.

 

The trend in recent times has been for GFS in particular to re-form the PV around Greenland/NE Canada toward the end of the month. A glance through the perturbations for the 12Z doesn't provide a clear picture though I do think a majority of the members at T+240 are showing a N or NW airflow.

[Frosty.]

Tonight's Ecm 12z ensemble mean supports the idea of an Arctic incursion at the end of next week and the subsequent cold and very unsettled outlook with the jet alignment becoming northwest / southeast.

The ecm is currently looking wintry from later next week onwards.

[Cloud 10]

A random spot check on the ECM and GFS from seven days ago (give or take a few hours) for today.

 

today..

 

gfs 7th March..  ecm 7th March..

 

 

Pretty impressive verification at that range.

 

 

[bluearmy]

As a singer once said - ' the times the times they are a changing' .......

[KyleHenry]

image.jpg

As a singer once said - ' the times the times they are a changing' .......

"Subterranean Homesick Blues"

[Frosty.]

18z op looking good later next week, Azores high building in bringing pleasant fine days, cold nights and light winds, very benign compared to ecm in same timeframe, the window of fine weather lasts through next weekend in the south before a gradual change to more unsettled early in week 2.

Edited March 14, 2015 by Frosty.

[Eugene]

Lovely pleasant weather next week, no cold or warm days to worry about, just perfect daytime maxs 7C to 13C.

[Frosty.]

The second half of the week ahead looks very pleasant with sunny periods and light winds according to the Gfs,ecm,ukmo and gem, becoming pleasant by day in the strengthening sunshine but turning cold at night with slight air frosts where skies are clear. Next weekend is more uncertain but I would say the further south you are, the better the weather will be, a decent window of fine weather on the way with less cloud and more sun.

[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 SUNDAY MARCH 15TH 2015.

 

THE CURRENT GENERAL SITUATION A cold but slack East to NE flow will affect all areas with a ridge over Scotland.

 

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

 

MODELS-2 WEEK HEADLINE A lot of dry weather with some sunshine and just occasional rain especially at first in the South and in the North later. Temperatures will be close to average or a little below overall.

 

THE GFS JET STREAM ENSEMBLE FORECAST The Jet Stream Ensemble Forecast shows the flow forced North over the Atlantic and Iceland due to a High pressure block over Europe. This pattern is maintained for some time before the general thrust of the flow will change axis to a West to East motion across the UK through Week 2 as High pressure collapses

 

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

 

GFS OPERATIONAL The GFS operational run today shows another week of weather across the UK with a strong anticyclonic influence, firstly from a ridge from the East and later by High pressure near or over the UK. Rather cloudy but dry conditions at first should give way to brighter conditions with a risk of night frost as the week progresses and the South should lose the chill ENE wind. Through Week 2 the trend is for Low pressure from the North to gradually take over with wind and rain at times in more changeable weather in more of an Atlantic westerly flow as a result.

 

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

 

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

 

THE GFS CONTROL The GFS control run is very similar in trend to the operational this morning with a change to more changeable weather from about a week from now. Having said that the influence of any changeable weather in the South will be muted as High pressure remains close by to the South with the strongest winds and heaviest rainfall always towards the North.

 

THE GFS CLUSTERS Apart from 5% of the GFS clusters this morning indicate a return to strong Westerly winds and rain at times for the UK two weeks from now. The 5% hold High pressure near the SE pf the UK with fine weather.

 

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 this morning shows High pressure to the East receding to new High pressure across the UK midweek with fine and dry weather with more sunshine. This recedes slowly West to allow a chilly Northerly into Eastern Britain come next weekend.

 

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

 

THE FAX CHARTS The Fax Charts show High pressure well in control of the UK weather this coming week with variable cloud cover, some sunshine especially later with some night frosts in the North as the High pressure ridge to the East transfers to a UK based one over the NW from midweek.

 

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

 

GEM GEM today shows High pressure largely in control over the UK in the shape of a ridge from the East at first and then from the West as new High pressure develops there later in the week. The only caveats to this are the NE breeze early in the week could reemerge for a time later in the week over the South and later the far North could see a stronger Westerly flow develop with some rain as the ridge slips further South across England.

 

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

 

NAVGEM NAVGEM follows the same format with High pressure developing to the West of the UK by soon after midweek replacing the chill NE flow over the South with an equally chilly Northerly over the East while most parts stay largely dry and increasingly brighter by day but with frost risk at night. 

 

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

 

ECM ECM this morning shows a similar sequence to NAVGEM and UKMO this week with High pressure relocating just to the West of the UK with various troughs sinking South over NW Europe late in the week and sending cold polar winds down over the West of Europe with the fragments of this affecting the East late in the week and more generally on the second pulse at the start of Week 2 when wintry showers could occur for a time. 

 

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

 

ECM 10 DAY MEAN(12z) The 10 Day Mean Chart shows a greater chance of Westerly winds over the UK with High pressure to the SW and Low pressure to the NW with a changeable pattern of weather likely over the UK in average temperatures overall.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The collapse of the European High next week is well supported with the evolutions thereafter gradually showing more of a tendeny for Atlantic Westerly winds and rain at times to develop slowly especially in the North.

 

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 97.3 pts and GFS at 96.6. At 5 days ECM  continues to lead the field at 91.2 pts over UKMO at 88.9 pts and GFS at 87.7. At 8 days ECM remains the leader with 66.8 pts over GFS's 61.3 pts. Then at Day 10 ECM retains superiority at 50.4 pts over GFS at 45.6. 

 

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 Changes in the weather synoptics over the coming few weeks will be relatively small but subtle with the overlying trend being for a lot of dry and fine weather for at least the first two thirds of the two week period. The surface conditions will all depend on location across the UK in relation to where High pressure bringing the fine weather sits. The far South and SE could well be plagued by a cold drift of wind from the NE at times especially early in the week while the North will see much lighter winds as well as more sunshine and the risk of night frosts. This risk increases somewhat later in the week as cleaner air looks like arriving for most as High pressure transfers close to the NW of Britain. Thereafter things gradually become less clear as most output suggests the desire to slip High pressure away West or South meaning Low pressure from the North could slip SE or East to the North and NE of Britain gradually increasing the risk of rain, wind and wintry showers to these parts later but from this morning's output it looks like any change along these lines may be well muted over the South for longer. In general though some very useable early Spring weather looks likely this week and possibly some of next too in the South where chasing cloud amounts will be the main feature day to day. The North too will share in a lot of dry weather too with some sunshine before the risk of rain from the North increases in week 2. What I can say with reasonable confidence though there will be no particularly unseasonably cold or mild conditions to deal with as temperatures through the period look like ranging from just above to just below average though frosts at night are more of a certainty for all if skies clear overnight. Rainfall through the two weeks looks like being below average generally and probably well below average across many parts of the South and SW.   

 

Issued at 08:00 Sunday March 15th 2015

[mushymanrob]

a pleasant calm week?...

luck will play a part, as spoiling cloud could well rob us of any pleasant sunshine, but at least its looking dry. the old double edged sword will raise its head too... sunny days could lead to frosty nights. i note that the current expected 'uppers' arent too mild so it could be chilly.

 

note the noaa 8-14 day chart suggests a flattening out of the upper air flow

 

 

this would suggest the gfs 00z 's fairly atlantic dominated run would most likely verify

 

a snapshot chart

 

in all, pretty normal, average, unexciting march weather, with the usual march mix.

Edited March 15, 2015 by mushymanrob

[Winter Cold]

Morning all

 

A definate shift towards the ECM runs of late from the UKMO 0z and GFS6z this morning, its possibly being proven as the correct way forward. Still time for change but strong signals still for a northerly incursion are there;

 

ECM:

 

        

 

UKMO:

 

Slightly further east with the trough but still not far away for T144. Much closer than it has been anyway to the ECM. No 850s available for UKMO unfortunately.

 

GFS:

 

  

48 hours behind the other two but goes the same way eventualy with the high backing west leaving us exposed to NW/N winds.

 

 

Still nothing mild showing up thats for sure, and as I said last night I dont expect my area to get much above 10c for the rest of March, but thats fine by me. Still plenty of time for that of course

 

     

Edited March 15, 2015 by Winter Cold

[John Badrick]

Morning all

 

A definate shift towards the ECM runs of late from the UKMO 0z and GFS6z this morning, its possibly being proven as the correct way forward. Still time for change but strong signals still for a northerly incursion are there;

 

ECM:

 

        

 

UKMO:

 

Slightly further east with the trough but still not far away for T144. Much closer than it has been anyway to the ECM. No 850s available for UKMO unfortunately.

 

GFS:

 

  

48 hours behind the other two but goes the same way eventualy with the high backing west leaving us exposed to NW/N winds.

 

 

Still nothing mild showing up thats for sure, and as I said last night I dont expect my area to get much above 10c for the rest of March, but thats fine by me. Still plenty of time for that of course

 

     

Looks like Spring still on hold, winter hanging on