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

[Frosty.]

Really impressive GEFS 12z mean this evening from the end of next week until potentially well beyond mid may, it becomes increasingly anticyclonic and warmer.

[049balt]

http://wxmaps.org/pix/prec4.html

 

 

Not everyone agrees on dry weather.

[Summer Sun]

http://wxmaps.org/pix/prec4.html

 

 

Not everyone agrees on dry weather.

 

Thats still the 00z still awaiting the 12z update

 

Temperature wise the light orange colours make an appearance in week 2 for some

 

[Kentspur]

http://wxmaps.org/pix/prec4.html

 

 

Not everyone agrees on dry weather.

Haha notice the little below average precipitation slit in my area- we do tend to be in a little drier zone compared to other places even in the southeast:-)

[049balt]

Thats still the 00z still awaiting the 12z update

 

Temperature wise the light orange colours make an appearance in week 2 for some

 

 

 

What is the difference between 00z and the 12z?

[Summer Sun]

The ECM ens continues to signal a rise in pressure from the end of next week the extreme north west could be prone some rain / showers at times, temperatures by day responding but maybe some isolated rural frosts where skies clear

 

Edited May 1, 2015 by Summer Sun

[bluearmy]

The question from last evening was whether the arrival of higher heights would be sustained. The 12z op gem coupled with the spread on the ECM end at day 10 does present some doubts on this.

[davehsug]

The ECM ens continues to signal a rise in pressure from the end of next week the extreme north west could be prone some rain / showers at times, temperatures by day responding but maybe some isolated rural frosts where skies clear

 

It goes a completely different way about it to it's previous runs though. Instead of a warm high building from the South, we get a cold high moving from the West.

[mushymanrob]

conflicting outlook from the main 3 this morning @ t144

 

ukmo anomaly charts say no

ecm anomaly charts say no

gfs anomaly charts say yes!

so the gfs 00z has the support of the noaa anomaly 6-10 dayer, which has been cosnistent. (well id suggest the gfs is closer to the anoms @ t144)

and the 8-14 day outlook, again is consistent

the ecm @240 the gfs @ 240

so according to the anomaly charts, the gfs has the best chance of being closest to the mark, that cold high the ecm suggests doesnt look so likely.

Edited May 2, 2015 by mushymanrob

[Gibby]

(Edit: added in summary for you - DRL)

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 SATURDAY MAY 2ND 2015

THE CURRENT GENERAL SITUATION Troughs of Low pressure will move slowly NE over Southern and Western Britain today and tonight and Northern and Eastern areas tomorrow.

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

MODELS-2 WEEK HEADLINE Unsettled at first with rain or showers. Perhaps becoming drier and warmer, at least for a time later.

THE GFS JET STREAM ENSEMBLE FORECAST The Jet Stream is currently blowing East over Southern England and France. In the coming days the flow tilts more SW to NE over Spain and France and then eases back North by next weekend to settle quite strongly in a NE diection across the British Isles through Week 2.

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

GFS OPERATIONAL The GFS Operational this morning shows Low pressure and troughs moving North over and to the west of the UK over the coming days. Spells of rain followed by more showery weather will occur between now and the middle of next week, heavy at times. Later in the week things simplify somewhat as the showery flow gives way to a more classic NW/SE split in the weather with rain at times in the North and West in a fresh SW flow while the South and East lie close to a ridge near the SE with planty of dry and rather warm weather though the unsettled conditions further to the NW may spread down South at times and more especially later.

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

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

THE GFS CONTROL The GFS Control run is similar to the operational in Week 1 but turns rather more generally unsettled again after a brief ridge next weekend. Late in the period pressure is shown to rise to the North with the best weather then likely over Scotland and the NW with lower pressure to the South and SW giving a little rain at times to the far SW.

THE GFS CLUSTERS The GFS Clusters today show the strongest bias lies towards a strong ridge across the UK from a High to the SW but there are swveral menbers which show something much more changeable.

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=ecmwfens&MODELLTYP=2&BASE=201502281200&VAR=pslv&HH=240&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

UKMO this morning shows Low pressure easing away to the NE later next week as pressure tries to recover to the South and SE and NW. As a result things will become drier across Central and Southern areas while the North take rather longer to lose the influence of this weekend and start of next weeks Low pressure with further showers at times.

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

THE FAX CHARTS The Fax Charts this morning show a complex series of troughs move NE across the UK in association with Low pressure drifting North to the West of Britain. Spells of rain will clear to showers on Sunday before another pulse of warm unstable air throws a trough NE later on Monday and Tuesday with some thundery rain in places before a simplified blustery and showery WSW flow takes hold for most midweek.

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

GEM this morning shows unsettled conditions next week with showers slowly giving way to drier conditions for a time as a ridge close to SE England later gains some supremacy. It isn't shown to last long though before a resurgence of Atlantic Low pressure extends to all areas with blustery West or SW winds and rain at times to end the period.

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

NAVGEM shows Low pressure moving slowly North just to the West of the UK next week maintaining unsettled and showery conditions for many until the end of the week when a new Low pressure from the SW takes another swipe at us before a ridge looks likely to build from the South over next weekend

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

ECM too looks unsettled next week as the complex Low pressure structure early in the week simplifies to a Low pressure area over Scotland with blustery west winds and showers for all. Later in the run High pressure does look like building across the Uk from the South and North with a cool North flow in the East gradually ebbing away.

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

ECM 10 DAY MEAN(12z) The ECM 10 Day Mean Chart from last night shows a strong ridge lying across or just to the East of the UK with fine and warm conditions likely to have developed for many by then but maybe less so towards the North and West.

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

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models continue to be hesitant on the extent and duration of High pressure in Week 2 of the period.

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 97.3 pts followed by UKM at 96.7 pts and GFS at 96.0. At 5 days ECM leads UKMO with 88.3 over UKMO's 87.6 pts with GFS at 84.6. At 8 days ECM remains the leader with 59.6 pts over GFS's 56.7 pts. Then at Day 10 ECM retains superiority at 43.8 pts over GFS at 41.4.

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.png

MY THOUGHTS The short term pattern is well agreed between the models with Low pressure ruling the UK weather for the next 4-5 days at least. Spells of rain and showers look like repeatedly moving up from the South or SW between now and Tuesday when a more sustained and blustery West or SW flow brings a mix of sunshine and showers for severeal days to most areas. The notable difference will be the increase in temperatures from those of late with the removal of any frost risk that's blighted some parts of late and the snowfall that parts of the mountainous areas of Scotland could see tonight and tomorrow. Then as we move towards next weekend there is reasonable cross model support for a High pressure ridge to build up from the SE to bring fine and warm conditions at least for a time but it's from this point that the models diverge in evolution as we move into the second week. There looks a 50/50 chance that some rain at times will return to many areas through Week 2 though with High pressure developed over Europe it maybe that it's just the North and West that experience the worst of this while the South and East maintain a lot of dry, bright and reasonably warm weather.

Next update from 08:00 Sunday May 3rd 2015

Edited May 2, 2015 by Polar Maritime
Added in summary.

[knocker]

This mornings anomalies are still showing uncertainty regarding the transition change around the 9th.

 

They both have the trough western Atlantic, ridge Greenland, a trough north of the UK but with different orientations and the HP southern Europe. The key would appear to be how far this ridges north to influence the UK. The ECM is showing more inclination to do this than the GEFS.

 

Moving on from T168 the GEFs swings the trough in the western Atlantic east thus pushing any likely ridging east as well so maintaining a W/SW flow over the UK. The ECM not so keen on this and opts for more pronounced ridging. All in all the jury is still out.

 

NOTE

After the upgrade on the 12th May the EC32 will extend to 46 days.

Charts weatherbell

 

[summer blizzard]

Downgrades have definitely begun this morning. Where there was once high pressure there is now..

 

[Frosty.]

I like the end of the Ecm 00z with very warm air from the south soon after, met office still going for a warmer and more settled further outlook.

Edited May 2, 2015 by Frosty.

[049balt]

I like the end of the Ecm 00z with very warm air from the south soon after, met office still going for a warmer and more settled further outlook.

The settled weather keeps being pushed out, still a very uncertain.

[Frosty.]

The settled weather keeps being pushed out, still a very uncertain.

The outlook doesn't sound much different from yesterday, from next weekend the south turns settled and warmer, then extending north, it's only the northwest of the UK which could be the exception.

[damianslaw]

Sticking to the reliable i.e. out to about Thursday next week, it remains an unsettled picture but milder than of late thankfully, meaning much less risk of frost. A troublesome trough will languish to the west of the country enveloping much of the country in a generally wet or showery airstream with some drier interludes more so in the SE, hopefully Monday should be a reasonable day for many.

 

Longer term - conflicting signals from the models today, but general theme from ensembles and Jetstream forecasts is for heights to the southwest to exert there influence bringing warmer conditions and more settled conditions. However, it is an uncertain outlook and its a fine balance between something rather more lukewarm and lacklustre developing as the atlantic continues to trouble most of us and something finer and settled for the majority of us (the far NW furthest from influence of heights less likely to see drier settled warmer weather). Odds though on drier settled warmer conditions settling in from the south, how far north and west these penetrate is the question.

Edited May 2, 2015 by damianslaw

[049balt]

Sticking to the reliable i.e. out to about Thursday next week, it remains an unsettled picture but milder than of late thankfully, meaning much less risk of frost. A troublesome trough will languish to the west of the country enveloping much of the country in a generally wet or showery airstream with some drier interludes more so in the SE, hopefully Monday should be a reasonable day for many.

 

Longer term - conflicting signals from the models today, but general theme from ensembles and Jetstream forecasts is for heights to the southwest to exert there influence bringing warmer conditions and more settled conditions. However, it is an uncertain outlook and its a fine balance between something rather more lukewarm and lacklustre developing as the atlantic continues to trouble most of us and something finer and settled for the majority of us (the far NW furthest from influence of heights less likely to see drier settled warmer weather). Odds though on drier settled warmer conditions settling in from the south, how far north and west these penetrate is the question.

Yes, that is the way I see things at the moment.

[ANYWEATHER]

Downgrades have definitely begun this morning. Where there was once high pressure there is now..

 

Yes ,stark differences from just a couple of days ago. This is quite typical of weather models, putting a huge anticyclone over the uk at day ten only to find the opposite in reality happens. Its the old adage, don't count your chickens until they hatch.....

[Costa Del Fal]

Yes ,stark differences from just a couple of days ago. This is quite typical of weather models, putting a huge anticyclone over the uk at day ten only to find the opposite in reality happens. Its the old adage, don't count your chickens until they hatch.....

Lol...

It's quite often true the other way round as well don't forget...

[Summer Sun]

UKMO shows the high building in during Friday

 

 

GFS meanwhile has the high south of the UK through out the run

 

 

GEM has a similar idea to GFS with the high not getting in

 

 

So at t144 its currently UKMO on its own for the high and beyond this GFS and GEM both show the high staying south of the UK

[049balt]

UKMO shows the high building in during Friday

 

 

GFS meanwhile has the high south of the UK through out the run

 

 

GEM has a similar idea to GFS with the high not getting in

 

 

So at t144 its currently UKMO on its own for the high and beyond this GFS and GEM both show the high staying south of the UK

O Dear, Summer on hold.

[mushymanrob]

O Dear, Summer on hold.

Eh?

Its spring!

[Summer Sun]

UKMO on its own for Friday and the high, ECM also showing low pressure like GFS and GEM

 

Edited May 2, 2015 by Summer Sun

[ANYWEATHER]

The g.f.s and E.c.m have really ditched the high scenario. E.C.M AT DAY 10 makes more of a brief windows of high pressure across southeastern Britain ,but this really sets the UK up for a brief Thundery plume. I say bring it on if this would verify! Way too far out for any detail, as we know at that timescale things will change!

[Frosty.]

The Ecm 12z shows very warm weather for the south and east later in the run, After reading comments like ..oh dear, summer is on hold I was expecting to see cold unsettled charts, instead I see 564 dam thicknesses into the south and very summery temperatures.