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

[johnholmes]

 mid to upper teens

 

doesn't bring temps higher than mid teens

 

and the difference ba?

I cannot see the necessity of making comment about those remarks.

It does of course depend on the position of the high and how much or how little cloud it brings with it. At 6 days let alone any further out it is all a bit academic is it not? Certainly IF the NOAA 500mb charts are correct then ridge dominated weather, once it develops, could well be with much of the UK for 10-14 days.

link

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

[Captain Shortwave]

Karl - you were referencing the ECM op 12z. That doesn't bring temps higher than mid teens, even allowing for the few degrees that the raw data usually undercooks. I would say that beyond nxt weekend, the upper ridge looks to move a bit further east which, in tandem with a mid Atlantic trough, should push temps up to a more springlike figure.

I think the issue with the ECM temperature predictions is shown up further considering when you look at the GFS for this coming weekend.

17C possible over Central/Northern England on Easter Sunday.

 

Even milder on Monday (19C possible in southern England)

 

It does turn cooler midweek as a cold front pushes southwards. The temperatures this weekend are very much dependent on how quickly we can lose the cooler northerly flow though. It does look like by Sunday that the majority should be in an anticyclonic west/north west flow with milder 850s, hence the improving temperatures. The second half of the Easter weekend looks better than the first half, this applies to rainfall too with some rain Friday into Saturday with Sunday and Monday looking mostly dry.

The UKMO looks better than the GFS beyond the Easter weekend with a stronger upper ridge persisting over the UK.

Settled and mild sums this up.

[bluearmy]

OMG. - what has happened to this place?

Karl made a statement based on the 12z ECM run. I was ONLY pointing out that the raw data did not support it. Temps (T2m) predicted across the uk to be in the area 10-12c. Even allowing for the ECM maxes to undercook by a couple of degrees, this makes the T2m likely to be 14, possibly 15 at highest. (Based on that raw data). Btw john , 15 and 20 is a fair way apart.

You can reference the raw ECM data for your location via yr.no

[Frosty.]

Easter Monday looks a beauty on this morning's Gfs 00z with favoured spots in the south close to 20 celsius. The ukmo 00z is a peach, as is ecm.

[IDO]

The models are now in sync as regards synoptics and from T36 to T144 it is UK HP dominated:

 

   

 

From T86 the GEFS show scatter for max 2m temps and I am not guessing what the surface temps will be as where the core high sits can make big differences. The T86 max varies on the GEFS from 9-15c. If there is a warm day in the mix it won't last long as the models have been consistent with pushing the high East/NE after D7:

 

 

From around D7 the models then differ. The GEM keeps a MLB with the HP cell close to the UK and at D10: 

 

 GFS op: 

 

^The GFS as I would expect when a possible change is a foot amplifies the pattern and send the HP NE/E and eventually for the upteenth time builds a HLB with the Atlantic trough trying to edge in:

 

Mean: 

 

^The mean suggests another op low cluster solution. ECM D9-10 charts don't disappoint as they send the High into Scandi, very predictable:

 

 

 

I suspect HP will ease east between D8-10 and we will get a more Atlantic flow. Maybe something like the control, with the Atlantic slowly easing the HP east so the SE holding on to the more settled weather for longer:

 

The JMA week 2 anomaly not far off that: 

 

Monday looks the best day over Easter, with potential 15c plus for the some. Otherwise I am not seeing much better than average temps for the next 7 days, and the main theme remains the settled week or so from around midday Friday. 

 

 

 

[mushymanrob]

i can understand the confusion here between models, as the exact nature of the forthcoming high is still in doubt. minor differences will lead to quite dramatic differing weather conditions... easterly draft = most likely cool and dull (except in the west), southeasterly = bright/sunnier and much warmer. the cloud issue will plague us for some time, restricting temps by day, preventing frosts by night.

at least itll be calm and dry....

[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 THURSDAY APRIL 2ND 2015.

 

THE CURRENT GENERAL SITUATION A slow moving front over SW Britain will move slowly NE later today followed by a cold front moving in from the West tonight with the whole frontal zone sliding SE into NW Europe tomorrow with the UK then lying in a chilly Northerly flow.

 

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 indicates the flow ridging over the UK and then turning South down over the North Sea and NW Europe soon on the Northern and Eastern flank of High pressure positioning. It maintains this theme for some considerable time before in the far reaches a more direct flow across the UK from the Atlantic looks possible as lower pressure develops to the NW.

 

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

 

GFS OPERATIONAL The GFS Operational this morning shows High pressure building to the West over the next 48 hours before settling across the UK late in the Easter weekend and through much of next week. The weather would become dry for all with increasing amounts of brightnss and while nevery overly warm pleasant Spring conditions seem likely with the risk of some frost by night. then in the second week the model drifts the High away to the East with a slow ingress of Atlantic fronts and SW winds likely by two weeks time with the return of more changeable conditions and occasional rain.

 

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

 

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

 

THE GFS CONTROL The GFS Control Run also shows High pressure likely to be based over the UK for much of next week with the same fine and bright weather shown by the operational. However, the High is eroded from the NW late next week and gradually elsewhere too as it then looks much more unsettled and windier in the second week with rain at times and average temperatures in SW winds.

 

THE GFS CLUSTERS The GFS clusters today indicate a pays your money and take your choice option this morning. 45% indicate rather chilly and unsettled conditions likely two weeks from now under Low pressure to the South or East of the UK while 55% favour something more settled under High pressure close to the East or South with milder temperatures as a result. 

 

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 High pressure settling down across the South of the UK by the beginning of next week with fine and settled weather with some sunshine, light winds and temperatures pleasantly up to average or maybe a little above if sunshine is pronounced enough but equally some chilly nights and the risk of frost at night.

 

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

 

THE FAX CHARTS The Fax Charts indicate High pressure developing close to the UK over the holiday weekend but with several old and decaying fronts leaving a legacy of cloud across the UK skies restricting otherwise sunny conditions and holding temperatures close to average in very light winds.

 

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

 

GEM GEM today shows High pressure aligning up over the UK in the coming days in a more favoured axis to give the Uk dry and increasingly bright weather with some sunshine and temperatures well up to average if not a little above by day but with chilly nights giving frost under any clear skies.

 

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

 

NAVGEM NAVGEM holds High pressure close to, over or just to the East of the UK with light winds for all, variable cloud cover and temperatures close to average. At the very end of the run some eroding of High pressure across the UK from the SW is shown but within the period of this morning's run it looks like it would stay dry until the end of next week at least.

 

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

 

ECM ECM is also showing a lot of High pressure from Easter and through next week and beyond. It's centre is biased towards the NE with just enough of a drift from Europe at times to temper conditions near the East and South Coast of England at times and especially later with a chilly breeze off the sea. Elsewhere and especially in the sheltered West some decent spells of sunshine could develop with temperatures responding well by day though with a hint of slight night frosts in shelter.

 

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

 

ECM 10 DAY MEAN(12z) The ECM 10 Day Mean Chart from last nights run shows High pressure well in control centred close to the UK and I see no reason why this morning's chart when released at 09:30 won't show something largely similar.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models continue to show a strong theme of High pressure over the UK from 48 hours time lasting for some considerable time.  

 

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 90.5 pts and GFS at 88.0. At 8 days ECM remains the leader with 68.3 pts over GFS's 63.9 pts. Then at Day 10 ECM retains superiority at 48.9 pts over GFS at 47.1. 

 

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 Things have firmed up on the positioning of the High pressure anticipated to take control of the UK weather from the second half of this weekend. There is universal support from the output that the High will locate over the UK for some considerable time from Sunday with fine and settled weather as a result. Also without the previous days charts indicating chances of an Easterly drift this morning temperatures could reach respectable and possibly somewhat warmer values in shelter and after a rather cloudy start to the period it looks like sunshine amounts will increase as we move through next week and drier air aloft moves in. Night's will still offer some unwelcome frosts should skies clear for any length of time but rainfall looks very unlikely for the vast majority of the UK for much of next week and that is something that can rarely be said when taking the UK as a whole for that length of time. Looking further ahead I have looked at GFS clusters and the longer term charts in general and GFS in particular shows something more mobile and changeable with some rain at times through Week 2 but one glance at the GFS clusters indicate little confidence in this outlook with conflicting forecasts within it's own members. ECM does show chinks in the High pressure's armour towards the end of the run and it does show a cooler Easterly feed of winds setting up by day 10 as the High migrates to Scandinavia with the odd shower close to the South. All in all though a good spell of useable weather to come and while it looks unlikely we will replicate some of the warmest conditions of Spring last year some very decent feeling weather is likely to be experienced by all for quite a while and it should begin to feel at last as though Spring has finally sprung.    

 

Issued at 08:00 Thursday April 2nd 2015

[Summer Sun]

Whilst UKMO and the others would give some chilly nights with frost still possible where skies clear they maintain the high well into next week, with the wind falling lighter from Saturday it will be feeling milder even if its cloudy but where the sun does break through it will be feeling warmer than it has done for quite a while

 

[Frosty.]

The GEFS 00z mean looks great this morning for those of us looking forward to a lengthy settled spell. Next week looks increasingly sunny and warmer with temperatures into the 60's F but with cold nights where skies clear.

[Frosty.]

The Ecm 00z ensemble mean also looks peachy this morning with a prolonged settled outlook and pleasant daytime temperatures but with chilly nights, it looks very good next week with anticyclonic domination.

[Milhouse]

Yes is does look good Frosty. The high has shifted a little more over the UK recently meaning there will be less of a cold drift around the top of the high and onto eastern coasts. However notorious cold spots like the NE cost of Kent will not fair too well i imagine. But for the majority of is it is set fair and pleasant.

[Frosty.]

The Gfs 6z shows plenty of settled and pleasantly warm weather during the next few weeks, especially across the southern half of the UK where high pressure has the biggest influence, daytime maximum temperatures are variable on this run due to the changing position of the anticyclone, there are some warm days in the south but generally averaging out around mid teens celsius which would be pleasant enough in lengthy sunny spells, nights look cold though with slight frosts where skies clear. The northwest of the UK in particular has occasional unsettled blips but for many it's a predominantly settled outlook.

Edited April 2, 2015 by Frosty.

[picog]

If those charts verify Frosty, it could be a very pleasant week in the south and west of the UK. It looks like most parts of the UK and Ireland will have some settled weather.

[mushymanrob]

the chart runs over the last few days have had a deal of uncertainty about the orientation, position and evolution of the high... but... the colder/unfavourable options appear to be decreasing and the warmer more favourable options (like frostys charts) appear to be gaining ground. and why not, it is april now.

[Summer Sun]

GFS and ECM bothing giving highs of 17c on Monday

 

 

If you can't see 17c on ECM clue north of Edinburgh

 

Charts WSI euro weather
 

Edited April 2, 2015 by Summer Sun

[Milhouse]

the chart runs over the last few days have had a deal of uncertainty about the orientation, position and evolution of the high... but... the colder/unfavourable options appear to be decreasing and the warmer more favourable options (like frostys charts) appear to be gaining ground. and why not, it is april now.

 

Just as you say that the GFS 12z lowers temps over Easter but the 12z from the UKMO is another very good run. So theres no reason why the GFS wont show higher temps again later/tomorrow.

[Frosty.]

The Gfs 12z shows winds eventually becoming SEly with more in the way of sunshine, much less cloud by the end of next week for the south and east compared to what we will have throughout Easter, hopefully we will see winds changing to more of a Sly / SEly as time goes on. Next week looks settled with high pressure in control and pleasantly milder than recently, especially when the sun comes out.

[Frosty.]

Tonight's Ecm 12z looks good, becoming settled with high pressure building in for several days with milder uppers and next week I think there will be a lot more sunshine and as a result, temperatures will rise into the mid teens celsius and a little higher in favoured spots, it's only by T+240 when cooler Atlantic air returns..it's a nice run.

[Milhouse]

You know when the 5c 850hpa line pays us a visit under high pressure its going to lead to very pleasant conditions. In any prolonged sunny spells id say high teens likely next week. Spring looks like its sprung judging by the ECM.

[Frosty.]

You know when the 5c 850hpa line pays us a visit under high pressure its going to lead to very pleasant conditions. In any prolonged sunny spells id say high teens likely next week. Spring looks like its sprung judging by the ECM.

I would have said high teens celsius but BA would probably have another dig at me like he did last night.lol

Edited April 2, 2015 by Frosty.

[damianslaw]

After a very unsettled period and distinctly wintry in northern parts, the models are projecting a much calmer benign springlike set up with anticyclonic conditions prevailing. An improving picture then, with plenty of dry weather ahead once we get tomorrow out of the way and feeling much more pleasant with light winds and hopefully increasingly sunny skies, the easter weekend could though be a rather cloudy affair keeping temps supressed somewhat but still around average.

 

Longer term - some subtle signs we might exchange the settled weather for something more unsettled and heights move to the north, but its a long way off. Its still a little too early for homegrown heat from high pressure overhead at this time of year unless we have a continental injection of air from a long draw southerly direction think late March 2012 or much of April 2011, if we were about 6 more weeks into the year i.e. mid May we would be looking at a notably warm period, alas the sun hasn't quite got the strength just yet, and the land is still only very slowly warming up...

[bluearmy]

I would have said high teens celsius but BA would probably have another dig at me like he did last night.lol

On the contrary Karl - the raw ECM op data supports high teens to end next week and into the weekend. Mind you, at 8/10 days out, that's likely to change.

[Frosty.]

On the contrary Karl - the raw ECM op data supports high teens to end next week and into the weekend. Mind you, at 8/10 days out, that's likely to change.

Tonight's Ecm 12z ensemble mean supports a very pleasant outlook. next week will become sunnier and milder.

Edited April 2, 2015 by Frosty.

[knocker]

A brief update on the latest EC32.

 

At T240 HP to the east of the UK with an upper trough Greenland running south with temps above average in the UK.

 

By T408 the HP to the east has dissipated and given way to a more zonal flow with LP to the NW and HP quite a way to the SW. Temps around average.

 

This scenario is still the analysis at T576

 

By the end of the run the LP becomes more dominant but still maintaining the zonal flow between the NW LP and the Azores HP to the SW. Temps tending below average.

 

Summary.

After the HP domination up to day ten it becomes far more zonal and quite unsettled, certainly between T240 and T384, with some periods of some very unsettled weather a distinct possibility. Certainly no signs of any sustained HP with the Azores cell pushed too far to the SW.

 

Looks like April showers are on the menu interspersed with more sustained periods of rain and some ridging from the SW.

[bluearmy]

ECM op introduces a shallow upper low for next weekend moving up from the sw. let's hope this is a rum run but ECM is usually pretty good at picking things like this up a week or so out.