Model Output Discussion

[Frosty.]

Disappointing meto update, mainly dry but rather cloudy sums it up but that is what the models are indicating next week and then something more unsettled which is in line with the latest gfs and ecm output, role on summer.

[Eugene]

http://www.wetterzentrale.de/pics/MT8_Manchester_ens.png

Looking very chilly and unsettled next weekend i notice a dip from yesterdays 850's as ever the end is an outlier.

[Rob]

nice southerly plume in the FI, low 20's out of that if it happens, but it will change

[Eugene]

before the high moves back in over us returning some very pleasant sunny dry warm weather .

LOL yes it will definately move over us and it will definately become warm in almost two weeks time just because GFS says so its the governor

[The PIT]

Looks like a slow gradual cool down is on the cards from both the ecm and gfs. A few days yet with temps above normal so make the most of it.

[Eugene]

UK Outlook for Sunday 25 Apr 2010 to Sunday 9 May 2010:

Staying unsettled for most areas, especially in the north and east, with rain or showers and feeling much cooler with temperatures generally below average for the time of year. Cold enough for snow at times over higher ground, especially in the north. Winds frequently moderate from the north or northeast, locally strong on windward coasts. The driest weather most likely in south-western parts. However there should be some good spells of sunshine in between the rain or showers, particularly in the south and west. There is a high risk of overnight frosts for some more sheltered parts.

Updated: 1301 on Sat 10 Apr 2010

People who take things too literally should worry more about this than the odd GFS FI outlier

[phil nw.]

Quote

UK Outlook for Sunday 25 Apr 2010 to Sunday 9 May 2010:

Staying unsettled for most areas, especially in the north and east, with rain or showers and feeling much cooler with temperatures generally below average for the time of year. Cold enough for snow at times over higher ground, especially in the north. Winds frequently moderate from the north or northeast, locally strong on windward coasts. The driest weather most likely in south-western parts. However there should be some good spells of sunshine in between the rain or showers, particularly in the south and west. There is a high risk of overnight frosts for some more sheltered parts.

Updated: 1301 on Sat 10 Apr 2010

People who take things too literally should worry more about this than the odd GFS FI outlier

Come on Eugene you know as well as i do that the Met.Outlook that far ahead is just as likely to change as GFS FI.

Settled but cooler during the next few days is all we can be reasonably sure of.

By the way what`s with the rude smiley?

[mushymanrob]

i hope all this dry weather in spring doesnt bode badly for summer

Edited April 10, 2010 by mushymanrob

[Frosty.]

People who take things too literally should worry more about this than the odd GFS FI outlier

Just as much chance of 18c and unbroken sunshine as that happening, latest models indicate we should make the most of another sunny and warm day tomorrow before the cloud rolls in early next week with patchy drizzle and temps several degrees down on current values, but who cares, most of us will be at work anyway.

[ANYWEATHER]

Slightly colder upper temps from today onwards for southeastern Britain, and much more in the way of cloud cover spilling in from the East as well as a noticable breeze picking up too! Looks as though the models are still singing the same tune for a Northerly ,but how potent and long it will last is of course impossible to say. Anyway some pleasant Spring warmth enjoyed by most over the last day or so and some more to be enjoyed picticularly in the North/Northwest over the next day or so....

[MR EXTREMES]

i think its a case of dont be fooled it very possible that most of the country is like to fair well places less likely to far best would be the east coast.

spring is here and its blooming lovely luv it.

my team in the fa cup final and 1 bbq already this year with garden getting done im happy.

we had a brillant winter models have done very well lately but might find it hard to place cloud cover.

[Derp Patrol]

No sign of a northerly on the GFS - looks like becoming cooler, but uppers hover around 0C for most of the country so it won't be cold, probably near average temps. Interestingly a southerly is shown in FI again in about 10 days time and the remainder of the run is warm, 20C likely from the setup being shown. This has been shown for a few runs in the past few days now, so I am pretty confident that things will warm up again in say 10 days time, fingers crossed

Edited April 10, 2010 by robthefool

[Costa Del Fal]

No sign of a northerly on the GFS - looks like becoming cooler, but uppers hover around 0C for most of the country so it won't be cold, probably near average temps. Interestingly a southerly is shown in FI again in about 10 days time and the remainder of the run is warm, 20C likely from the setup being shown. This has been shown for a few runs in the past few days now, so I am pretty confident that things will warm up again in say 10 days time, fingers crossed

Unfortunately it appears to be quite a large outlier on the ensembles.

[Ben_Cambs]

No sign of a northerly on the GFS - looks like becoming cooler, but uppers hover around 0C for most of the country so it won't be cold, probably near average temps. Interestingly a southerly is shown in FI again in about 10 days time and the remainder of the run is warm, 20C likely from the setup being shown. This has been shown for a few runs in the past few days now, so I am pretty confident that things will warm up again in say 10 days time, fingers crossed

http://www.null/two/ensembles/

Very little support from the GEFS ensembles in that respect though. The Northerly is becoming less likely to make an impact due to the Scandi trough being pushed North Eastwards on each run. Because its FI, ECM and GFS are majorly different to eachother at T+240 with GFS going for a pressure build from South East Europe while the ECM 0z went for LP over the UK, with the HP retrograding towards the US Eastern seaboard + Canada, that would open up an attack from the South West. IMO, best to stick within the T+144 timerange for trends and anything further out can only really be a possibility out of a few.

[damianslaw]

Tentative signals from some of the models today (ECM) longer term for the current high to ridge sufficiently north west for an attack from the south west, this is a pattern we saw in late feb and late march, it would result in a very unsettled cyclonic pattern, southerly parts could get quite warm as a southerly draw develops ahead of any low pressure.

Something to watch in the coming days, we don't want a return of the negative west based NAO steering low pressure over the country. A weak short lived northerly would be the symptom of the above, a stronger longer lasting northerly not so, I hope the latter occurs as this could result in the high then ridging back over the country.

[Cheese Rice]

The northerly keeps on showing on the GFS, although it wont happen the GFS is showing lows of -6.c which if it comes of would be very impressive for late April, especially as there isn't any snow cover projected.

Edited April 10, 2010 by 10123

[mushymanrob]

the fax at t120 allows a retrograde high and northern trough to introduce the northerly by c t168 as shown by the current ecm. so after the cloudier week a cool down is pretty inevitable. this is all perfectly normal, im sure no one expected these past few glorious days to continue forever!

[Frosty.]

A disappointing week coming up compared to this sunny weekend, much more cloud and temps several degrees colder than currently, cooler air already making inroads from the east with a max of 14c in london today, yesterday reached 19.4c in scotland and 20c is possible today in the highlands, astonishing to think just over a week ago there was a blizzard up there! High pressure will continue in the coming week but the pressure will be slowly seeping away with a much more unsettled weekend and following week, the ecm 00z looks particularly disturbed towards the end of it's run.

Edited April 11, 2010 by Frosty039

[Guest]

The northerly keeps on showing on the GFS, although it wont happen the GFS is showing lows of -6.c which if it comes of would be very impressive for late April, especially as there isn't any snow cover projected.

It wouldn't be that impressive 10123, sorry

Look at this from Torro, it shows record min temps for different times of year in the UK:

http://www.torro.org.uk/TORRO/britwxextremes/mintemps.php

-12.8C in late April, -9C in mid-May, -5.6C in the second week of June.

Tulloch Bridge was -2C last night, so another 4C in a colder airmass should be pretty easy to attain.

[The PIT]

Away from Scotland it looks like a long spell of fairly dry uninteresting weather coming up with the High only briefly control in deep FI allowing some rain into Northern Central England. ECM a bit more aggressive in deep FI with the low pressure pushing south but fairly well agrees with the GFS until well into FI.

So uninteresting often cloudy weather to come for the foreseeable future.

[Frosty.]

Aye, parts of scotland will probably hang on to reasonable spells of sunshine and decent temps during the next 5 days being closest to the main high whereas a cooler/cloudier NE'ly flow looks like taking control further south across the majority of the BI.

[damianslaw]

Still beond the reliable timeframe, however, both GFS and ECM in agreement towards the end of next week, for the high to retrogress north west and far enough to bring down a trough from the north introducing a colder unsettled northerly airstream.

UKMO less bullish with a northerly, keeping the high closer to the country, but the signals are becoming stronger for a northerly of sorts to develop later next week.

Key question, how long lasting will the northerly be and how potent. Every chance of shortwave development and low pressure pulling down from the north west giving less of the cold showery scenario and more of the cool wet cloudy variety with possible snow to northern hills. As I said this is still a long way off in weather terms, in the reliable timeframe turning cooler as the high begins to pull in cooler air from the north east particularly to southern and eastern parts, but dry and settled with no rain, cold nights for the north west.

[Snowyowl9]

Long while since we had a 2nd half april cold spell,which the the GFS is showing today.

http://www.wetterzentrale.de/archive/ra/1995/Rrea00119950420.gif

http://www.wetterzentrale.de/archive/ra/1995/Rrea00119950422.gif

http://www.wzkarten.de/pics/Rtavn2161.png

[Thundery wintry showers]

In the near term most parts look like having another sunny day tomorrow but quite chilly near the east coast with the wind off the sea. Low cloud looks like being more widespread over eastern England from Tuesday until Thursday, while western England stays sunny. The high pressure should be far south enough to keep all of Scotland, bar east-coast fringes, sunny and quite warm. So while we are staring at a spell of low cloud for some I don't think it's set to be as prolonged or intense as the models had suggested a few days ago.

The northerly in about a week's time looks potentially interesting but one big issue with it is that numerous shortwaves keep being spawned over northern Scotland, cutting off the polar flow and tending the weather more towards cool and wet rather than cold bright and showery- we may well see that west based negative NAO crop up again. The first chart Snowyowl9 posted (20/4/95) was a good example of a "clean" northerly which brought four consecutive days of sunshine mixed with wintry showers- there were some impressive hailstorms in the North East that day- but I think such a northerly is only about 20-30% likely from the current set of outputs.

[Rob]

Long while since we had a 2nd half april cold spell,which the the GFS is showing today.

http://www.wetterzen...00119950420.gif

http://www.wetterzen...00119950422.gif

http://www.wzkarten....s/Rtavn2161.png

It's one to watch but its still a long way off, any judging by the inconsistency of the models recently most likely won't happen