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

[legritter]

Some good posts on our forum ,thanks for studying the charts and giving a picture of what could happen .

I,m still looking after elderly relatives but its nice to pop in and see what mother Nature could be sending our way .

so after a break down later tomorrow next week could deliver more very high temp for April and if low pressure does move in from the west some action weather for us to get our teeth into .But at this range detail becomes unsure ,certainly not boring gang .  STellas all round .

[Frosty.]

The Ukmo 12z shows high pressure returning from Monday, and as the Gfs shows, the high transfers east enabling a much warmer continental airmass to push north across the UK, much as we have now with gradually rising temperatures again next week with lots of sunshine and increasing humidity by the second half of next week with a risk of thundery showers later...this really is exceptional for mid April..this is turning into a very good spring now.

[Winter Cold]

Good agreement tonight from GFS and UKMO and T144:

 

 

 

Becoming very pleasent again next week, with very respectable temps once more:

 

 

Im liking the continued suggestion from the models of thunderstorms later next week, thats the best bit of a warm, humid spell!

 

GFS still going for some higher level blocking it has to be said, later on in the run:

 

   

[Milhouse]

Low pressure over the Bay of Biscay helping to draw some very warm air northwards during the middle of next week

 

[Lincs Observation]

The Ukmo 12z shows high pressure returning from Monday, and as the Gfs shows, the high transfers east enabling a much warmer continental airmass to push north across the UK, much as we have now with gradually rising temperatures again next week with lots of sunshine and increasing humidity by the second half of next week with a risk of thundery showers later...this really is exceptional for mid April..this is turning into a very good spring now.

 As i alluded to last week and looking for trends in a long term sense i think this will be a recurring theme over the next few months, My best guess would be a decent summer to come with these aimasses from deep south popping up from time to time giving Hot periods interspersed with incursions from the west. The stall IMO was set out months ago and the azores high has been a repeat visitor on and off all winter.

[Frosty.]

Really nice Ecm 12z with +10 T850 hPa during the middle of next week, summery charts in mid april..BANK

[A.J]

Really nice Ecm 12z with +10 T850 hPa during the middle of next week, summery charts in mid april..BANK

indeed it is.....Looking at the air mass source, T850 values and high thickness values both in the lower and mid atmosphere, I do wonder if somewhere in central southern UK might even hit 25C mid week?

Edited April 9, 2015 by ajpoolshark

[ANYWEATHER]

Well at last some weather to talk about from the Gfs ! Cooler and unsettled with rain and April showers and some fresh Atlantic air for the weekend ......High pressure builds early next week , to allow some perfect  blue skies , but gardeners beware with some air frosts just about anywhere across the nation.....Then pressure falls it gets warmer and more humid then some welcome rain falls later next week . So a Mixed outlook ,something for everyone on this run!!

[Summer Sun]

Mid 20's in the south if this comes off?

 

[Frosty.]

I agree with the comments about the ecm tonight, somewhere in the south would reach 25c next week and looking at the latest ecm 12z ensemble mean, these are very summery charts and I think next week will become even warmer and also more humid with an increasing chance of T-Storms from later next week, I also agree with an earlier post about the current pattern repeating as we go through late spring and into the summer with the Azores high playing a big part. I'm really liking the current output..a lot.

[stodge]

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

 

AO moving back strongly positive after the brief negative spell last weekend.

 

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

 

Set to get very high again before a sharp drop back for most members at mid-month. Monday's GFS 12Z Op demonstrates the high AO with virtually no heights at the Pole:

 

http://modeles.meteociel.fr/modeles/gfs/runs/2015040912/gfsnh-0-84.png?12

 

Again, the NAO catches my eye with big scatter mid month:

 

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

 

That to me supports the possibility of falling heights to the SW and rising heights to the North. GFS has toyed with this idea over several FI runs and ECM hints at it tonight so the possibility of a more amplified spell after mid-month is very much on the cards with perhaps the cards not falling too favourably for the UK with a more unsettled and cooler regime tasking over.

 

http://modeles.meteociel.fr/modeles/gfs/runs/2015040912/gfsnh-0-324.png?12

 

This would suggest to my eyes a negative NAO.

[Captain Shortwave]

Much better ECM tonight in my view, less progressive in the evolution and more believable in my view.

Really warming up Tuesday and Wednesday with temperatures hitting the low twenties widely, perhaps reaching the mid-twenties in lucky spots. Thundery showers could break out towards the south and west of the UK.

At the moment the likely scenario will be a breakdown of sorts by the end of the week with high pressure more likely than not to reassert itself, though temperatures will fall to nearer normal values.

ECM ens shows a weak ridge through the UK, though things could change as the anomaly is rather weak.

Still an early taste of summer is likely during the middle part of next week. 

 

A lot of talk was about a cooler spell, but in the south only Saturday has a maximum below 15C (11-13C), even Sunday now is looking mild though northern areas will be cooler throughout the weekend and into the start of next week.

Edited April 9, 2015 by Captain shortwave

[Cheshire Freeze]

Mid 20's in the south if this comes off?

 

 

Looking at that, I'm more interested in any convective potential- just a few tweaks needed here and there...

Edited April 9, 2015 by CreweCold

[bluearmy]

The cut off low to our south west is going to cause issues to the modelling in the approach into fi.

Note there is a parallel ECM op running ahead of an impending upgrade. Wonder if sylvain can get his hands on it??

Currently available on weatherbell.

[shaky]

The cut off low to our south west is going to cause issues to the modelling in the approach into fi.

Note there is a parallel ECM op running ahead of an impending upgrade. Wonder if sylvain can get his hands on it??

Currently available on weatherbell.

totally agree with you.bluearmy!!noticed difficulties in the models as early as t96 hours in recent days!!for example ukmo wants to push the high away east as early as 96 hours whereas the ecm and gfs look better in prolonging the warm spell next week!!!anything could happen!!

[Polar Maritime]

Yes some big swings in the models as per the last few days, GFS does keep throwing a cool N/N/E flow out in the run as a trough sinks South over the UK, As BA says all down to the cut-off low and where it ends up. 

 

Edited April 10, 2015 by Polar Maritime

[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 FRIDAY APRIL 10TH 2015

 

THE CURRENT GENERAL SITUATION A cold front will move East across the UK tonight and tomorrow with a colder Westerly airflow following to all.

 

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

 

MODELS-2 WEEK HEADLINE Becoming more changeable over the North with rain at times next week while the South and East stays largely dry and bright and possibly quite warm at times.Possibly rather colder for all later with frost at night.

 

THE GFS JET STREAM ENSEMBLE FORECAST The Jet Stream forecast shows the flow settling across the UK on a NE track over the next few days. It then moves back North towards a position to the NW of Scotland where it remains for the rest of next week and weekend. then there are signs of it dicing SE across the UK as pressure builds across the Atlantic.

 

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

 

GFS OPERATIONAL The GFS Operational this morning shows High pressure largely in control of the UK weather over the next week to 10 days as it shiffles around largely to the SE of the UK at first and then over the UK later. Then through Week 2 pressure rises over the Atlantic which threatens the introduction of colder NW or North winds across the UK with some showers, wintry on hills. 

 

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

 

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

 

THE GFS CONTROL The GFS Control Run has the same theme with the South seeing the biggest benefits of High pressure to the SE or over the UK next week before week 2 also features a change to cold and unsettled conditions thereafter as Low pressure establishes to the NE and High pressure to the SW or West.

 

THE GFS CLUSTERS The GFS clusters have firmed up on the shift towards colder and more unsettled weather at the two week point with Low pressure likely to be near Scotland and a chilly West or NW flow with rain at times likely across the UK. There is very little support for any meaningful High pressure affecting the UK at that point from this morning's pack.

 

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 shows High pressure building for a time early next week positioned close to the SE with warm and bright conditions likely for the South and East for a time. It is not shown to last though as a cold front moves across the UK from the West or NW by Day 6 with fresh and bright weather returning.

 

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

 

THE FAX CHARTS The Fax Charts reflect the rise of pressure early next week replacing the troughs that meander about across the UK from tonight and again over Sunday.

 

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

 

GEM GEM today also shows High pressure largely controlling conditions across the UK but increasingly in the wrong place to maintain the warm and fine weather currently. Splicing the spells of High pressure controlled weather will be occasional troughs moving SE across the UK each bringing a little rain and lowering temperatures with winds eventually settling more from a colder North or NW point.

 

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

 

NAVGEM NAVGEM too shows High pressure to the SE brnging fine and warm conditions early next week gradually becoming replaced by colder air from the North as the pressure gradient is reversed to High pressure to the NW later although on this run dry weatehr is largely maintained.

 

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

 

ECM ECM today is showing quite complex synoptics as we move through the run, largely under High pressure though with complications. The centre of the High is shown to the South early next week with some warm air wafting across the UK. It then looks like High pressure across the Atlantic ridges East across the UK with some fresher air which then leads us into a quiet and benign period of light winds, variable cloud, the odd shower in the SW and temperatures respectable enough but best in the South.

 

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

 

ECM 10 DAY MEAN(12z) The ECM 10 Day Mean Chart  from last night shows very flat conditions across the UK in 10 days with mostly High pressure dominated weather with plenty of sunshine and pleasantly warm conditions.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trends this morning are continuing to show an increased risk of rather cold air moving down from the North after the next week although ECM in particular looks less keen on this scenario with fine and bright conditions under High pressure close by.

 

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 97.6 pts followed by UKM at 97.1 pts and GFS at 96.3. At 5 days ECM  continues to lead the field at 90.6 pts over UKMO at 89.4 pts and GFS at 86.9. At 8 days ECM remains the leader with 65.5 pts over GFS's 61.5 pts. Then at Day 10 ECM retains superiority at 47.8 pts over GFS at 42.4. 

 

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 Although the theme of the next two weeks weather largely remains one of High pressure there is a difference of opinion on how it affects conditions across the UK through the second week in partcicular. The current warmth will be interrupted over the weekend with more changeable conditions for a time before High pressure is shown to rebuild early next week returning warmth and dry weather especially over the South. Then as we move towards the end of next week divergences in the models occur ranging from a cool down from the North or NW as High pressure transfers to the Atlantic whereas ECM shows a more benign air pattern across the UK towards the end of it's run with a lot of dry weather but with quite a bit of cloud and the odd shower. GFS is more extreme with it's theme of colder conditions in Week 2 with sufficient depth to the cold air from the North to allow wintry showers and frosty nights. So a lot of fluidity in the predictions from later next week but I don't think High pressure is ever likely to be far away from the UK at any time but the one certainty from this morning's output is that the positioning of High pressure is very instrumental in what type of High pressure based weather we enjoy, be it warm and sunny or cooler and more cloudy. Time will tell over subsequent runs as hopefully models firm up on these longer term details in what looks a fairly benign spell of weather.

 

NOTICE

 

There will be no report from me tomorrow here or on the forums but the next report will be bright and early on Sunday morning.. 

 

Issued at 08:00 Friday April 10th 2015

[Summer Sun]

Staying in the shorter term Tuesday and Wednesday look the peak for the warmth next week for England and Wales

 

[Winter Cold]

Yes its looking like a tricky few days for the models. The euros are not agreeing this morning at 120 and 144 which is a sign of difficulties:

 

ECM:

 

  

 

 

UKMO:

 

  

[MP-R]

Yes its looking like a tricky few days for the models. The euros are not agreeing this morning at 120 and 144 which is a sign of difficulties:

 

ECM:

 

  

 

 

UKMO:

 

  

 

Not exactly the same but broad theme is warmer feed from the continent by midweek then possibly cooler after then with a reassertion of high pressure by the end of the week.

[summer blizzard]

Euro seems to have backed off doing much with the Biscay low and instead has a slack, warm flow. 

 

[Captain Shortwave]

Some impressive temperatures forecast for Tuesday and Wednesday still, 20-24C widely I suspect across England and parts of Wales.

GFS 06z

Tuesday

 

Wednesday

 

That said Scotland and Northern Ireland do look like missing out with fronts bring cooler and damper conditions.

 

The GEM for the last few runs has brought a weakening cold front through quite quickly Wednesday into Thursday, this picked up by the UKMO now and also the GFS. There is the chance of some thundery rain being pushing up from the Bay of Biscay but that is pure conjecture at the moment.

The ECM is settled and warm (albeit the temperatures steadily fall away), but its evolution is different to the rest now, though cut off low scenarios do tend to see large swings in the output, even at short range.

Edited April 10, 2015 by Captain shortwave

[knocker]

Looking at the anomalies I wouldn't have said the ECM is that different to the GEFS. Both have ridging to the SE with the cut off low just west of Portugal giving a southerly draw.

Charts weatherbell

 

[Frosty.]

The Gfs 6z shows a rapid warm up, it's really only Saturday which is noticeably cooler and fresher and from Sunday it's warming up again, by Sunday it's pleasantly warm, by Monday it's warm and tues / weds become very warm with somewhere reaching 24c 75f..The first half of next week looks superb for most of England and Wales, even warmer than this week.

Edited April 10, 2015 by Frosty.

[Frosty.]

The GEFS 6z mean shows the middle of next week being the warmest and most settled period across England and Wales, from there the trend is less warm and less settled and further on it looks much cooler and generally unsettled. I think we will see the warmest weather so far this spring during the first half of next week but then turning cooler later next week and more unsettled from the northwest.