Model Output Discussion 31/03/14 onwards.

[knocker]

Indeed. Some 850 and 500 means from the 12z.

Edited April 28, 2014 by knocker

[Frosty.]

High pressure domination is looking more likely, a significant change in the 6-15 day met office update with increasingly warmer days next week and a reducing risk of ground frosts. The cold has been toned down from sharp frosts to ground frosts, chilly days have been replaced by average temperatures with pleasantly warm sunny spells and mainly dry weather for the bank holiday weekend, only exception to the fine outlook is the northwest corner of the uk where the atlantic could gain control but for most of us it is looking very good by the time we reach the weekend onwards.

[Polar Maritime]

Yes, After this cool blip the models are showing we could be heading for some proper seasonal Spring weather.

[draztik]

GFS still not on-board!

 

 

GFS 18z, ECM 12z - Bank Holiday Monday.

 

This is almost a week away, so much uncertainty lingers. GFS is the odd one out into mid term, when compared to the ens. But the ensembles have been useless recently... so who knows.

 

As for the latest EC32, its showing a warm May .... throughout! That is another flip from its previous update!

 

My hope; we get a settled May and June and a changeable cooler July & August. Thank you, please! And that is often the case... after a mild April-June... summer doesn't always live up to expectations.

Edited April 28, 2014 by draztik

[Frosty.]

I can see why most of the coldies have left the forum in disgust, no cold weather last autumn, winter and now spring..it's been a horror show for coldies but hopefully our luck will change later this year. The models are now firming up on another warm and settled outlook and hopefully the azores high will visit the uk often this summer.

Edited April 28, 2014 by Frosty.

[knocker]

The plot thickens

 

A brief glimpse at the GFS 00z run shows a significant change to the previous consensus for the weekend and it will be interesting to see the ECM after espresso time.

 

Regarding the upper air the colder air from the Atlantic is intruding into Ireland by Monday with the warmer air pushed SE into France. This has led to a somewhat different surface analysis.

 

On Saturday the UK is in a slack area of high pressure with no precipitation and temps in the high 50s to low 60s. Some SW winds just sneaking into western Ireland.

 

By Sunday the high has sneaked off to Hamburg and the low pressure if effecting Ireland and NE Scotland with a frontal system lying west of Ireland. Patchy rain in the north and quite cool in Scotland but okay in England with temps in the low to middle 60s.

 

By Monday the Atlantic low has taken over giving a SW flow over the UK and the high pressure has collapsed. This is some change of direction. Giving wet weather in Scotland, Ireland and Wales with an accompanying drop in temps in all areas except the east of England to mid to high 50s. The latter area will still be in the low to mid 60s.

 

All temps for 12z.

 

Never count your chickens but on the other hand……………………..

Edited April 29, 2014 by knocker

[shaky]

Gfs still not agreeing that is crazy!!I have this horrible feeling gfs is right or we will get a middle ground solution at best!!

[Polar Maritime]

Yes the GFS is showing unsettled conditions moving in off the Atlantic by the 4th, After a few days of dry weather. ECMWF delays this by a day or two..

 

Edited April 29, 2014 by Polar Maritime

[Summer Sun]

We a different picture this morning compared to previous runs will be ineresting to see what the ensembles show later

 

 

UKMO still looks fine for BH monday but the Atlantic is looking closer

 

 

GEM however looks fine for the longest period

 

 

ECM also shows the high declining into next week

 

Edited April 29, 2014 by Summer Sun

[Captain Shortwave]

Disappointing runs this morning. Trust the GFS to trump every other model including its own ensembles at the worse possible moment where 25C probably could have been reachable next week given some of the runs we saw.

The whole bank holiday weekend still looks decent though. 

[IDO]

Looking at the GFS mean at T192: 

 

It remains constant with its trend for lower heights from the west early next week. It had been split 50-50 for several days but the the last 5/6 runs been slowly heading towards any heights collapsing. The Control and op have led the way for the last few runs highlighting this development. This is now looking the way forward.

 

ECM as per usual, run with a solution and then suddenly flip and today looks like it may be the turning point.

 

ECM at T168:    T192: 

 

Lots of people knock the GFS but they spotted this a while back and again it appears they may have nailed the trend.

 

Further out on the GEFS it looks like height rises from the AH is only delayed and by D10 the ensembles are suggesting a return: 

 

 

This at the moment is showing high confidence, the only variable is how far north it will ridge. Early days yet for this scenario.

Edited April 29, 2014 by i'm dreaming of...

[knocker]

Looking at the ECM. Maintaining a blocking upper ridge on Sunday but after that a retreat to allow in the Atlantic air leading to a surface analysis about 24 hours behind the GFS.

 

I would like to say one thing en passant. Yesterday I was smacked on the back of the legs for advising someone to consult professionals when requiring a forecast. I stick by that.

Edited April 29, 2014 by knocker

[Gibby]

HERE IS THE LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM TODAY MONDAY 28TH APRIL 2014.

 

THE CURRENT GENERAL SITUATION. The UK lies in a slack East flow around Low pressure over France. A trough of Low pressure is expected to move NE across the SW approaches later tonight.

 

GFS GFS today shows High pressure sliding down across the UK over this coming weekend with dry and fine weather for many over the Bank Holiday weekend with inherently cold air, especially by night before things warm up early next week as the High slips South allowing Westerly winds to develop. The trend then is shown for troughs of Low pressure to cross the North and eventually the South too at times but with some further injections of higher pressure now and again with fine and dry interludes in temperatures close to average.

 

UKMO High pressure moving down over the UK at the weekend will settle near Southern England on Bank Holiday Monday with fine, dry and increasingly warmer weather with sunny spells. NW Britain may become rather cloudier later but are shown to stay dry out until the expiry of the run.

 

GEM The GEM operational today shows High pressure maintaining control over most of the UK through next week as it drifts from it's position over the UK at the weekend to a point to the east through the week. Temperatures as a result would rise with some warmer continental air wafting up across the UK later in the week with any cloud and occasional rain restricted to the very far NW.

 

NAVGEM sides with GFS  with lower pressure moving back down over the UK through the early part of next week with some rain at times for all, first in the North but later in the South too as Westerly winds bring more cloud and a Westerly breeze increasingly evident through next week.

 

ECM too this morning shows High pressure close to Southern England losing grip somewhat as we move through next week, at least for a time. In this period the fine weekend will be eroded by cloud and some rain moving down across the UK for a time through the middle period of next week. Temperatures would become somewhat warmer, especially in the sheltered SE later.

 

MY THOUGHTS There has been a few changes since yesterday morning's output. The anticipated lengthy spell of High pressure shows signs of being interrupted at least for a time after the Bank Holiday Weekend as much of the output indicate a strong risk of a period of more unsettled weather to move down across the UK for a time through the midweek period. My own thoughts are that beyond this High pressure will re-establish itself towards the South or SW with a NW/SE type scenario setting up with Southern and Eastern Britain becoming dry and bright while NW areas see the biggest risk of seeing more in the way of rain at times in a SW flow. Temperatures look like settling close to average though it could become quite warm in the SE at times later.

[Frank Trough]

Disappointing runs this morning. Trust the GFS to trump every other model including its own ensembles at the worse possible moment where 25C probably could have been reachable next week given some of the runs we saw.

The whole bank holiday weekend still looks decent though. 

 

I think the disappointment is relative! Bank holiday weekend still looks excellent at this stage (considering it is a bank holiday!) - bit of a break down next week before high pressure rebuilds for the following weekend! The other good news is that the cold has gone now - in fact (I can't copy and paste charts in my new browser? annoying) the 850's now don't go below zero for Hampshire at all. Different oop north obviously but compared to what was being shown it's a big change.

 

Plenty of time for tweaks to bank holiday weekend for better or worse but at least Saturday and sunday look like almost countrywide decent days. I'm looking forward to some drier weather - it's been really wet down here since Easter, surface flooding again places.

[shaky]

Back to reality again from the ecm this morning and its just typical that the gfs is right again and the ecm backs down!!hey at least we still got a very good warn and sunny bank holiday to look forward to!!

[Frosty.]

The cold has gone is the story of the weather models for the last 6 months, the cold was always in FI on the models and self destructed before it reached the reliable timeframe, very bad luck for all the coldies but hopefully this coming autumn and winter will be much better. Latest models show another fine and pleasantly warm spell on the way.

[I remember Atlantic 252]

Back to reality again from the ecm this morning and its just typical that the gfs is right again and the ecm backs down!!hey at least we still got a very good warn and sunny bank holiday to look forward to!!

 

ECM FI fantasy again last night, GFS looks right again for next week, could change back but unlikely, GFS is showing the likely, average May setup

[MR EXTREMES]

it would seem the only model showing something remotely summer like is the gem but this model has a strong bias towards high pressure as seen through winter.

ecm and gfs difference is the ecm wants lower pressure to track futher north , now if the ecm is correct then in time we can see it either remaining average spring like with low pressure slowly exerting its influence from the nw, or not shown yet but the azores heights building from the sw pushing lower pressure north of the uk into scandi area although there are some what higher heights here in the later ecm output.

 

the gfs has lower pressure more into the west of the country moving more into southern areas of the uk but other than a brief flirt to the ne of colder weather it looks to be heading towards a more normal average spring like setup.

 

although i feel theres more changes to come over the next few days my thinking would be a more higher pressure dominated outlook.

[knocker]

Running through the ECM Ens mean 500mb anomaly for next week doesn't fill me with confidence given the changing evolution over the weekend. It has the AZ ridge over the UK but weakening. This leads from cyclonic influence over the UK in mid week to a weakish ridge by Friday. Frankly this is just out of interest as I'm sure it will change long before that.

Edited April 29, 2014 by knocker

[draztik]

Ecm control for bank holiday Monday now increasingly unsettled, esp so for the NW but no area immune from a more Atlantic influenced pattern. Kudos to the venerable gfs for picking up on this trend first. Seemingly dragging the other models with it.

Ecm control /Holiday Monday

Edited April 29, 2014 by draztik

[Frank Trough]

Ecm control for bank holiday Monday now increasingly unsettled, esp so for the NW but no area immune from a more Atlantic influenced pattern. Kudos to the venerable gfs for picking up on this trend first. Seemingly dragging the other models with it.

Ecm control /Holiday Monday

 

The 06z delays the onset of the Atlantic a little compared to the 00z and delivers a better bank holiday nationwide (the southeast still looks best, though).

 

But yes, at present it seems like the GFS idea of heights being shunted away next week is a good call, also supported by today's METO update. The details will change, though. Have a look at what the models were showing for today 6 days ago.

 

I'm wondering what model this guy uses?

 

"Jonathan Powell, forecaster for Vantage Weather Services, said temperatures are going to hover below-average for at least a week. He said: "We are looking at a northerly flow of air coming in from the Arctic. With windchill this could push thermometers as low as -5C. "Temperatures are going to sink decidedly below average for the time of year with the risk of very sharp frosts and a cold and bracing Bank Holiday next Monday".

 

He has a different concept of "bracing" compared to me, that's for sure.

 

Edited April 29, 2014 by New Forest Gump

[draztik]

Yep, the gfs 6z is more in keeping with its ensemble mean over bank holiday wkend, before diverging and giving us a more unsettled mid week! As for Jonathan Powell's assessment? I got nothing!

[DR(S)NO]

The 06z delays the onset of the Atlantic a little compared to the 00z and delivers a better bank holiday nationwide (the southeast still looks best, though).

 

But yes, at present it seems like the GFS idea of heights being shunted away next week is a good call, also supported by today's METO update. The details will change, though. Have a look at what the models were showing for today 6 days ago.

 

I'm wondering what model this guy uses?

 

"Jonathan Powell, forecaster for Vantage Weather Services, said temperatures are going to hover below-average for at least a week. He said: "We are looking at a northerly flow of air coming in from the Arctic. With windchill this could push thermometers as low as -5C. "Temperatures are going to sink decidedly below average for the time of year with the risk of very sharp frosts and a cold and bracing Bank Holiday next Monday".

 

He has a different concept of "bracing" compared to me, that's for sure.

Well , it was only a few days ago that this chart was being shown.....the weather can make fools of us all.Whats being shown today isn't necessarily correct either.

[William of Walworth]

Still time for more switches in positioning and detail before the weekend.

 

But in general I'm agreeing with the consensus on here right now -- High Pressure influence likely to be more transient/shortlived than yesterday's (overprogressive?) models were pointing towards (I've only scanned 00z and 06z output so far though)

 

On the brighter side for the rain averse, the actual weekend into Monday still looking dry for most, and even quite pleasant in some more Southern locations.

Edited April 29, 2014 by William of Walworth

[knocker]

Yep, the gfs 6z is more in keeping with its ensemble mean over bank holiday wkend, before diverging and giving us a more unsettled mid week! As for Jonathan Powell's assessment? I got nothing!

 

Agreed the 06 has backed off 24 hours. On Monday the frontal system is still just west of Ireland with the UK in a slack southerly from the rapidly retreating east HP. This naturally effects the earlier temp. assessment for the good giving a dry day and temps in the mid 60s for many.

 

Pretty cyclonic for the rest of the week with a low 996hPa in the North Sea on Thursday.

Edited April 29, 2014 by knocker