Model Output Discussion 14th May 2012 Onwards

[tinybill]

well looking deep into F1 no real sign of any warm weather its looking unsettled till at least to may 31 at the moment

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=6

Edited May 15, 2012 by tinybill

[shedhead]

I think those of us looking for dry, warm and sunny weather have to accept things are not about to change dramatially anytime soon, but as I said yesterday the slow, steady improvement looks set to continue, with drier, warmer conditions gradually taking over as the 2nd half of May unfolds.

[reef]

The GFS and ECM seem to be completely at odds with each other for the weekend and beyond, so I think its wise not to look beyond then without a bucketload of salt.

The GFS shows a shortwave pushing down the country in the latter half of this week, giving two cool, wet days in the southern half of the UK with Northern areas remaining, cold, cloudy but dry under an easterly flow. This then moves south before another small shortwave moves into Scotland on Sunday giving heavy, possibly thundery showers in the North, but turning drier in the south. This then moves southwards but fades away over Northern England leaving us in a weak northerly flow. The air is cold enough to give sunshine and heavy showers to most areas, though it is eventually mixed out to leave warmer days as the Azores high tries to push in. Shower activity generally remains for the south however.

The ECM on the other hand shows low pressure anchored to the south as high pressure builds to the North of the UK. As with the GFS, the initial low over the south then moves away into the continent but instead we are left with a strong north-easterly wind over much of the country. This leads to the usual scenario of dry and cloudy weather in the eastern and central areas with temperatures held up by night and pegged down by day. Far western areas would be sunnier and warmer, though as ever its difficult to predict cloud levels in such a setup.

So although 850hPa temperatures look to be much higher, it may very much be the case that weather on the ground isnt much better (possibly worse even) than now. Theres still a lot of uncertainty though beyond Friday, with the GFS in particular looking extremely messy. In the mean time its looking like a cool northerly flow with a couple of harsh frosts tonight and tomorrow night for the time of year.

[johnholmes]

ECMWF and UK Met along with its Fax charts are probably a better guide out to T+120/144 than GFS at the moment in my view.

[shedhead]

ECMWF and UK Met along with its Fax charts are probably a better guide out to T+120/144 than GFS at the moment in my view.

Rarely is that not the case imo.

[bluearmy]

High pressure could be the new trend according to what Matt Hugo has tweeted today

Thats a tad misleading gavin. becoming more settled (or less unsettled) as we head throught the remainder of may and less chilly. does he say settled ? as for june, no strong signal. your post would lead many to think we are going to see spring quite soon.

[Downburst]

Thats a tad misleading gavin. becoming more settled (or less unsettled) as we head throught the remainder of may and less chilly. does he say settled ? as for june, no strong signal. your post would lead many to think we are going to see spring quite soon.

June? lets not worry about that as we need something out of May yet and are only half way there. If we can stick to 2 weeks out we are already over extending ourselves. I am happy with the 12z GFS forecast as it builds that ridge this way. Clearly an improved outlook on that run and some signs at long last of a break in the unsettled theme.

[Zenarcher]

Looking at the GFS and ECM ensembles for Saturday 19th of May to Friday 25th of May. This weekends weather looks changeable but in terms of pressure we are likely to see high pressure building to our North meanwhile lower pressure sits to the South.

For next week between the 21st and 25th they both show signs of high pressure taking charge. At first its looking likely it will be in charge over the North before becoming more widespread down to Southern parts. I would expect temperatures to be rather warm at times just depends where the high pressure builds from.

[johnholmes]

High pressure could be the new trend according to what Matt Hugo has tweeted today

come on Gavin stop misquoting the man.

Had you looked at a more lengthy comment from him, see this link, you would perhaps not have made the above comment. His ideas generally fit with both longer term UK Met or indeed what some others have also been suggesting.

this is the link

http://matthugo.wordpress.com/2012/05/15/mid-may-analysis-longer-term-thoughts/

My own views have been well posted regarding how the 500mb charts are showing some POSSIBLE slow changes.

[Bristawl Si]

come on Gavin stop misquoting the man.

Had you looked at a more lengthy comment from him, see this link, you would perhaps not have made the above comment. His ideas generally fit with both longer term UK Met or indeed what some others have also been suggesting.

this is the link

http://matthugo.word...-term-thoughts/

My own views have been well posted regarding how the 500mb charts are showing some POSSIBLE slow changes.

"Misquote" - i think that's an understatement JH.

I've just read Matt Hugo's thoughts and they're screaming more of the same to me well into June but with a slow rise in temps, which would be expected for June anyway.

Has Gavin D got access to a completely different version?!

[andy100]

Changes are finally showing now GFS has high pressure building across the North from the 21st it then covers all the country by the 25th

http://www.jp2webdes...o.uk/ds/gfs.htm

Yawn.

[Alex]

A sudden change of direction showing on the GFS output this evening, with some warm uppers filtering into southern areas from the continent early next week before high pressure pushes down from the north at the latter stages of next week. Fingers crossed!

[The Northern Ramper]

Caution should remain but the FI trend for several days now is for high pressure to build during next week.

[tinybill]

A sudden change of direction showing on the GFS output this evening, with some warm uppers filtering into southern areas from the continent early next week before high pressure pushes down from the north at the latter stages of next week. Fingers crossed!

diff to what john hammomd is saying rain at the weekend again

[Summer Sun]

diff to what john hammomd is saying rain at the weekend again

The beeb forecast sun for today only yesterday and it was flaming cloudy and wet, the sun has just got out so I shouldn't worry too much, 24 hours seems hard enough for them to forecast some times,

Back to the models GFS is much more like it lot's of HP around and warmer temps fingers crossed GFS is taking us in the right direction

http://www.null/ds/gfs.htm

[ribster]

The beeb forecast sun for today only yesterday and it was flaming cloudy and wet, the sun has just got out so I shouldn't worry too much, 24 hours seems hard enough for them to forecast some times,

Back to the models GFS is much more like it lot's of HP around and warmer temps fingers crossed GFS is taking us in the right direction

Gavin, you've been touting this for weeks and weeks, if I had a fiver for every time you've said it, I'd be booking a holiday to somewhere with some warm sunshine! Odds, are as we edge ever nearer summer, one might expect to see some warmer temps and sunshine, at this rate it will be the longest day! As it happens, it's rained here in some form or other for the last 45 days...

Edited May 15, 2012 by ribster

[Summer Sun]

ECM also builds high pressure for next week

Nice to see the models becoming consistant

Edited May 15, 2012 by Gavin D

[PubliusEnigma]

ECM also builds high pressure for next week

Nice to see the models becoming consistant

Gav.. this is a bit of an outlier to my mind as is not consistent with the Met O medium ranger, the Beeb outlook and most other long range forecasts.

This is however is the perfect HP set up..................If it were only late january ! :o

This place would be in meltdown with ramping galore..

[PubliusEnigma]

With such a long fetch over the cold north sea, despite the milder uppers, an inversion and low SST would lead to possibly worse weather than we have now with maybe four or five days of continuous overcast raw, dull and damp days with patchy light rain on and off. Continental NW Europe away from the British Isles would fare much better though.. Also the high on the OOz Ecm run at T240 is centred just WSW of Scotland.. Lets see if the 240hrs on the 12z migrates this High to Greenland opening up a blast from the N or NE ?

Edited May 15, 2012 by PubliusEnigma

[Summer Sun]

ECM end's with High pressure in control

[Alex]

diff to what john hammomd is saying rain at the weekend again

I never said dry, warm uppers would mean better temperatures and I said high pressure from late next week.

[PubliusEnigma]

And there we have it.. The north pole via the back door.. Easterlies over the uk, COLD easterlies fed from the pole via Scandinavia..driven around a Cold High near Iceland ( previously centred west of Scotland on the 00z with potentially a lot of moisture in its circulation given the fact its centred in Mid North atlantic.

NO sign of anything warmer away from the channel Islands and maybe the far SW of England..

[camiscool]

enigma stop it. picking out bad charts to wind people up.

[PubliusEnigma]

Why do HP's never topple or sink in Spring and Summer but nearly always do in winter.. There's a conundrum for you !!

[Alex]

And there we have it.. The north pole via the back door.. Easterlies over the uk, COLD easterlies fed from the pole via Scandinavia..driven around a Cold High near Iceland ( previously centred west of Scotland on the 00z with potentially a lot of moisture in its circulation given the fact its centred in Mid North atlantic.

NO sign of anything warmer away from the channel Islands and maybe the far SW of England..

Well that's definitely at odds of the upper temps being shown, quite widely 5-10c across all areas by the end of next week on both the GFS and ECM. These uppers would most definately with a bit of sunshine produce anything between 20-25c.