Model output discussion - 20th Feb onwards

[mb018538]

To be honest, anything after a week of temps 3-5c below average will be welcome! Nice to see some early signs of the Greenland mega-block being eroded away, with the trough that will nag the east of the UK dissipating somewhat.

[stodge]

Morning all

Well, some signs of an erosion of the Greenland heights at the end of next week but far from a done deal as we've seen a couple of attempts modelled before fade away as we enter high-res so another couple of days I think before we can be certain...

GEM sends the LP from Denmark NW to Iceland which is very odd while both GFS and ECM take a more gradual approach with the Azores HP ridging NE as the heights lower to the far NW. A plausible evolution but again we aren't there yet.

A week or so of below average and sometimes well below average temperatures is booked for us.

[knocker]

Not particularly cold 700mb or 500mb temps the analysis for the 25th

 

[knocker]

The EPS 8-13 anomaly continues the theme of eroding the Greenland block and pattern change. We have a filling upper low east of Iceland with some ridging mid Atlantic. Ergo a WNW flow with some unsettled weather mainly in the north with temps still a little below average.

[NO LONGER POSTING]

I am more interested in the coming days at what the models predict temp wise on the ground and what actually happens.

 

I think the temperature won't be as low (away from the night) in anyway sunshine that happens.. Given we are rapidly approaching May and the sun gains ever more strength 

 

Personally where a 10-11 may show 13-15 maybe achievable and in any sun that will feel pleasant out of the wind

Time will tell! 

 

 

[Frosty.]

1 hour ago, weatherguru14 said:

Seems your nitpicking from one run as failed once again.,,not suprising though..

Indeed I cherry picked the best chart from the Gfs 00z which just so happened to be the last chart of the run but hey, I'm just looking for signs of a major warm up after the upcoming cool / cold spell is over and I'm sure there are many others who share my view!

[Milhouse]

47 minutes ago, Surrey said:

 

 

Personally where a 10-11 may show 13-15 maybe achievable and in any sun that will feel pleasant out of the wind

Time will tell! 

 

 

Even in the northerly air stream there are pockets of less cold uppers which spread south during next week so the potential is there for some calmer, less cold days where it should feel fairly pleasant. That is before the winds turn round to a milder westerly direction at the end of the week.

[Tim Bland]

surprised there isn't more excitement about the impending northerly and late arctic blast.  Meto supporting the output for snow & potentially accumulating at night early next week.  I know it is spring but the weather over the next 7 days will be from boring with thunder, Hail & snow all in the forecast!  

 

 

[knocker]

2 hours ago, Frosty. said:

Indeed I cherry picked the best chart from the Gfs 00z which just so happened to be the last chart of the run but hey, I'm just looking for signs of a major warm up after the upcoming cool / cold spell is over and I'm sure there are many others who share my view!

I'm sure that many would agree with the sentiment expressed but but perhaps not with the method employed for the search. 

[Frosty.]

1 minute ago, knocker said:

I'm sure that many would agree with the sentiment expressed but but perhaps not with the method employed for the search. 

The method employed was fine, this is the model output discussion and its ok to mention any timeframe, all I did was show what I considered to be the best looking chart on the Gfs 00z run. All I'm doing is looking for signs of warmth beyond the imminent much cooler spell.

[IDO]

After the last few days it is disappointing to see the JMA 28 day forecast, with the UK stuck under lower pressure as higher pressure migrates into a HLB.

Week 2:   Week 3-4: 

Bringing below average upper temps. This is similar to how GFS is panning out in FI, though CFS has the HLB further east. So a while to wait before we see the 18-20c we saw over the last couple of days, assuming the forecasts are correct; possibly not until June at the earliest!

Thankfully rainfall totals look low so overall fresh with some sunshine between the showers and some cooler days incoming. 

[karyo]

2 hours ago, Tim Bland said:

surprised there isn't more excitement about the impending northerly and late arctic blast.  Meto supporting the output for snow & potentially accumulating at night early next week.  I know it is spring but the weather over the next 7 days will be from boring with thunder, Hail & snow all in the forecast!  

 

 

It looks very exciting with much more convective activity than a similar set up would offer a couple of months ago!

Last Saturday was a great example here with sunshine one minute and thnder with hail and snow the next! Beautiful sky too with plenty of cbs.

Karyo

[Summer Sun]

GFS shows high pressure slowly building in by the end of next week

Still chilly but maybe the bank holiday weekend will be settled if not chilly

Edited April 21, 2016 by Summer Sun

[knocker]

The GEFS anomalies in the 8-13 range continue with the pattern change that has been indicated for two or three days now. Erosion of the Greenland ridge and the UK trough and increasing influence from the Azores HP., Thus upper wind backing NW and temps gradually rising to average.

Edited April 21, 2016 by knocker

[knocker]

The ecm ops has high pressure pushing in from the west late next week which is temporarily interrupted by a rogue shortwave emanating from the Iceland area from Thursday which briefly deepens and then fills en route to Scotland by midday Saturday bringing a brief return of the northerlies with the HP just to the rest. This almost certainly will be subject to reevaluation in future runs.

[Frosty.]

I wish we had seen charts like these within the reliable timeframe during the winter, just imagine how cold it would have been with a sustained Arctic flow for around a week or so which is more or less what the Ecm 12z op is showing this evening with reload after reload of arctic air digging south with the strongest thrust during the first half of next week. It looks like we will see a return of night frosts and becoming cold enough at times for the showers to turn wintry with a mix of rain, hail, sleet and even snow, the snow especially on northern hills but also in some of the heavier showers further south but we should all see sunny spells too and out of the chill Northerly breeze and in any decent sunshine it would still feel pleasant but the outlook is unseasonably cold for much of the next 7-10 days judging by this run.

[wishingforsnow]

1 hour ago, knocker said:

The GEFS anomalies in the 8-13 range continue with the pattern change that has been indicated for two or three days now. Erosion of the Greenland ridge and the UK trough and increasing influence from the Azores HP., Thus upper wind backing NW and temps gradually rising to average.

I'm loving the sight of the Greenland high slowly being eroded after these reloads of Artic air. Spring 2016 is a mixed bag so far in my opinion but the sooner that Greenie high is eroded to make way for warmer weather the better.

As for next week, I don't think it's looking particularly bad with sunny spells as well as the odd passing shower but it will feel unseasonably cold again. It's like a yo yo   Also the sight of snow for some could be welcoming considering we just had another snow starved wet and windy winter, depending on how one feels about Springtime snow.

Edited April 21, 2016 by wishingforsnow

[Fourty Point Three Degrees]

in my opinion the very first signs of summer start appearing around 10th May with almost full blown summer daylight. I hope snow wont be on the menu, seeing snow showers within the long summer daylight hours just spoils things.

[knocker]

The NOAA and ecm 6-10 are singing from the same hymn sheet and the pattern transition is becoming evident but more so when one moves on a couple of days

The EPS 8-13 has a slack area of low pressure Greenland/Iceland area with weak troughs western Atlantic and North Sea and strong ridging Western Russia. Just weak influence from the Azores to the SW thus a zonal unsettled flow with temps a tad below average. This develops into a trough mid Atlantic by the end of the run. The NOAA 8-14 is not in complete agreement with this but it's not a million miles away.

 

Edited April 21, 2016 by knocker

[knocker]

A quick look at the latest EC32 means update

A start of the pattern transition Friday with the weakening of the Greenland ridge and the movement of the trough situated to the east NW thus beginning the process of backing the upper flow. It should be said that this doesn't indicate an immediate panacea temperature wise but a move in the right direction,Weather still unsettled.

This process is pretty rapid and by May 2nd the Greenland ridge is no more and we have a slack low pressure area Greenland/Iceland and a zonal flow with weak troughs western Atlantic and to the east with the Azores HP maybe just influencing the south of the UK thus the unsettled weather perhaps more concentrated to the north.

Briefly, until May 9th we have the Azores HP ridging very adjacent to the UK so a period of more settled weather and temps picking up quite well without any indication of it being blazingly hot. Too soon for that.

After that a return to zonality but no strong signals so best left to the professionals.

Regarding the Bank Holiday it looks touch ago as it's caught in the transition but certainly looking more hopeful particularly if you are Cornwall bound.

Back to the GFS this morning

Blizzard alert

It has a shortwave developing south of Iceland Thursday which it deepens and moves SE to be over Scotland in the next 24hrs. Be afraid, be very afraid. This is just posted out of interest and comes with a major health warning.

 

Edited April 22, 2016 by knocker

[Polar Maritime]

Certainly a 'Wintry' week coming up, With a pretty deep low moving South by Friday as Knocker points out giving possible blizzard conditions for parts of the North.. Lots to keep tabs on over the coming days with interest.

Edited April 22, 2016 by Polar Maritime

[mb018538]

UKMO in their update last night seem fairly bullish about things changing in the 10 day range, with higher pressure moving in. It does appear that this northerly isn't going to stay around forever, and something will change at the turn of the month.

Just to add, the extended ECM and associated ensembles look promising this morning after May begins.

Edited April 22, 2016 by mb018538

[knocker]

The ecm also moves the HP in from the west on Thursday and develops the low Iceland but tracking it SE north of Scotland before saying helllo to the Atlantic.

[Gibby]

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON FRIDAY APR 22ND 2016

THE CURRENT GENERAL SITUATION High pressure is receding away to the West of the UK over the next day or so with an occluded front close to Southern Britain moving away South too tomorrow leaving the UK in a protracted cool Northerly airflow across the UK for some considerable time thereafter.

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

CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK Colder uppers are spreading down from the North across the UK over the next few days with the freezing level falling to as low as 2000-3000ft across all parts of the UK by the end of the weekend. Any showers will fall as snow above 1000ft at times especially across the North and East.

http://www.snow-forecast.com/maps/dynamic/uk

http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif

MODELS-2 WEEK HEADLINE Becoming colder at the weekend with cool nights and sunshine and showers looking likely with a continuing night frost risk thereafter. Perhaps becoming less cold as we enter May.

THE GFS JET STREAM FORECAST The Jet Stream is in the process of change as the flow becomes directed South across the UK over the next few days. It then remains in situ for the next week under the influence of Low pressure to the East of the UK. Then through the second week the theme is for the flow to back to a West to East flow and later a cyclonic flow as Low pressure transfers to the west of the UK.

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

GFS OPERATIONAL The GFS Operational Run today shows a sustained cold and showery Northerly flow developing through the coming days and lasting for much if not all of next week. Then the pattern slowly changes passing through a transitional change of shallow and still showery Low pressure close to the UK before ending up with a deep Low developing just to the NW of the UK with wet and windy but less chilly conditions finally arriving towards the end of the second week

GFS CONTROL RUN The theme of the Control Run is very similar to the Operational in relation to the colder phase of the run with next week and next weekend maintaining a cool and showery feel. However, the run couldn't be different in it's latter stages as on this run High pressure replaces Low pressure crossing the UK and ending to the North with a warmer and continental feed of winds across the UK with a lot of dry and fine condition to end the period.

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

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

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=144&mode=0&carte=0

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=384&mode=0&carte=0

GFS ENSEMBLE DAY 14 DATA Still very mixed messages from the Clusters today  which show a bias of 60/40 in favour of High pressure ruling the roost over the UK in 2 weeks time. There is still a sizeable group though who still prefer a much more cyclonic pattern with rain at times across the UK at the same time point.

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 The UKMO model this morning still shows a cold and showery pattern developing across the UK in the coming days as Low pressure to the east and later NE dominates. Winds will be blowing from between North and NW strongest in the NE where the most frequent showers wintry on hills are expected with the risk of frost at night under any clear skies.

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

THE FAX CHARTS The Fax Charts today show a Northerly flow becoming established across the UK and far from straightforward as troughs are shown to be pulled South in the flow with cloudier skies and some rain being replaced by the coldest phase of the spell early next week under a more direct cold and showery Northerly by then.

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

GEM GEM this morning shows a sustained and cold run this morning with Low pressure to the Northeast or East and then over us for a time later maintaining cool and showery weather under Northerly sourced air throughout the 10 day period with a continued risk of frost at night for many and some snow over the hills at times for some.

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

NAVGEM NAVGEM N/A at time of issue. 

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

ECM ECM also shows the cold Northerly intensifying early next week with showers and very cold winds blowing down from the North before the pattern eases later as pressure rises to the South leading to lighter Westerly winds warming things up later and killing off the showers from all but the far North and hopefully limiting the risk of frost much more by the end of the period as rain moves across the North and West under more traditional SW winds.

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

ECM 10 DAY MEAN (12z) The 240hr mean Chart from last night is continuing the theme of the UK gradually lifting out of the cold spell as Low pressure gradually establishes closer to the NW of the UK with winds gradually settling West or SW with rain at times and higher temperatures together with some rain at times especially across the North and West.

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

NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS Changes in the models remains slow but there is a continuing if by some models a tantalising shift away from the coldest conditions lasting too long this morning as the theme of milder Westerly winds arriving towards the latter part of the period continues to be shown.

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.6 pts with UKMO at 99.4 pts and GFS at 99.3 pts.  At 3 days ECM is leading with 97.2 pts to UKMO's 96.5 pts while GFS lags behind at 95.4 pts. At 5 days ECM leads with 88.4 pts to UKMO at 86.2 pts and GFS at 83.0 pts. Then at 8 Days ECM has the leading spot from GFS with 61.9 pts to 56.0 pts. Finally at Day 10 ECM has the lead from GFS with a score of 43.2 pts to 35.9 pts.

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png

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  Today's output shows more of the same in terms of the UK moving into a cold spell of Northerly winds and how we eventually find our way out of the rut late next week or beyond. What we have today is an occluded front across the far South and SW of the Uk today making for it's own injection of cool and rather gloomy weather with some rain while the rest of the UK have another bright and dry day. The rain in the South is then chased away by tomorrow as cold Northerly winds begin to embrace the UK between Low pressure to the East and High to the West. The gradient between these systems then steepens next week with a stronger and unusually chilly spell for late April with a mix of sunshine and showers, falling as snow on hills and where showers don't occur frosts at night are likely widely. It's not until late next week when the cracks begin to appear in this set-up as winds look like backing towards the West or even SW with milder conditions albeit with rain at times developing. However, models like GEM this morning enhance the length of the cold spell throughout the 10 days and it is just one of many options on the table beyond next week. What can be said with some certainty there is no heatwave on the cards any-time soon although with bright sunshine between the showers and the additional hours of daylight we have now it' certainly not all doom and gloom and it maybe that it's just patience that is required before the current synoptic pattern realigns to offer us something rather warmer. Time of course will tell. No report tomorrow or Sunday. Will hopefully be back next Monday with some better news for warm seekers.  

Next Update Monday April 25th 2016 from 09:00

[Summer Sun]

London's snow row is upto 15 next Tuesday I don't recall seeing London get this high during all of winter

100 miles or so to the east the snow row for Norwich only gets upto 9 on Tuesday

120 miles or so up in Birmingham for Tuesday its 0 and the high is just 3