Model Output Discussion

[frostyjoe]

Good to finally see a change afoot with something a bit more interesting from Wednesday with the high slipping away, a short period of southwesterlies veering round to a more WNW direction.

Tuesday:

http://www.wetterzen...cs/Rtavn721.png

Wednesday:

http://www.wetterzen...cs/Rtavn961.png

Thursday:

http://www.wetterzen...s/Rtavn1201.png

Friday:

http://www.wetterzen...s/Rtavn1441.png

Saturday:

http://www.wetterzen...s/Rtavn1681.png

Could be a wet one.

So another few days of cool(th) then the temps on the rise with some rain, spring looks like finally arriving.

so its going to be cloudy and wet mild rubbish like this all week!!!

[DaBrigg]

We will finally get a taste of tropical-maritime air later next week by the looks of things. The high dew-points should be very noticeable after so many months of cold dry air. It will feel quite balmy, although not necessarily pleasant, if accompanied by breezy drizzly weather.

Probably the wrong place to ask, but is this the coldest the southern north sea has been for a few years?

Probably, and I suspect they will remain below average for some time yet. The UK Sea Surface Temperature thread has dropped back a few pages, perhaps it was time it was resurrected.

[sandstorm2]

They're here:

http://www.netweather.tv/index.cgi?action=charts;type=fax;sess=

Thanks Paul

SS2

[Thundery wintry showers]

Looks like the mild weather still shows up on the charts, but a large downgrade of the dry sunny high pressure stuff, with some fronts moving up from the SW at times. With an emphasis on tropical maritime air we are unlikely to see any "sunshine and showers" type stuff- just frontal moderate/persistent type rain with some windows of drier brighter weather in between.

It's up in the air as to whether we get some interludes of warm sunshine or it just ends up dull and damp. Much depends on the precise timing of fronts which is hard to pin down at this stage- the GFS 06Z has a very warm day in 6 days' time for instance with temperatures rising to 15-16C in places in sunshine ahead of the arrival of the subsequent frontal system.

Btw, although I can see what the post really means, "balmy but not necessarily pleasant" is technically a contradiction- see here:

Definitions of balmy on the Web:

* mild and pleasant; "balmy days and nights"; "the climate was mild and conducive to life or growth"; "a soft breeze"

But whatever the effects on human activities, the upcoming weather certainly looks like it will help to bring our wildlife into full flow with mild temperatures and plenty of moderate rain.

[DaBrigg]

Btw, although I can see what the post really means, "balmy but not necessarily pleasant" is technically a contradiction- see here:

I think I meant to use the word 'sultry' more so than balmy. Perhaps both words are little over-dramatic to describe run-of-the mill unsettled Spring weather, but I suspect the the air will feel noticeably moisture-laden relative to what we've become acclimatised too. "Mild and close" would be the most appropriate description perhaps.

I find it difficult to keep warm when dew-points are very low, regardless of what the temps are doing, but I might be a bit hyper-sensitive to such things.

[Thundery wintry showers]

Aye, hope you didn't take it the wrong way- I had a feeling you might have meant something along those lines- just a bit of pedantic-ness! Mild and unsettled (but as above, by no means dull and drizzly all the time- plenty of warm sunshine suggests itself for Tues/Weds on the GFS 12Z). We are still not a million miles away from an evolution to cold afterwards though, for we do get a ridge of HP develop over Scandinavia at around T+168 and it looks not dissimilar to the HP there around 12 March 2006 which was underplayed by the models beforehand.

Edit: UKMO having none of it though- on the UKMO I see nothing but mild SWs, probably cloudy and wet for the most part but the T+120 chart looks like HP might be close enough to give some very warm temps + sunshine towards the SE. Unless the ECM falls into line with UKMO tonight though I am more inclined to believe GFS.

[Ben_Cambs]

It seems very likely now that we will see milder weather, but in return expect it to be unsettled and wet for many areas by next weekend.

Cambs GEFS ens pressure:

.

Cambs GEFS ens 850's:

[Thundery wintry showers]

Unless the ECM falls into line with UKMO tonight though I am more inclined to believe GFS.

It has- so the implication is an extended mild spell, looking quite bright/warm midweek next week then probably cloudy wet and windy for most towards the end of the week (the SE could potentially see some very high temps though if HP is close enough to the SE).

Even though March has begun cold, a below average CET is starting to look no more than 50% likely IMHO.

[phil nw.]

It has- so the implication is an extended mild spell, looking quite bright/warm midweek next week then probably cloudy wet and windy for most towards the end of the week (the SE could potentially see some very high temps though if HP is close enough to the SE).

Even though March has begun cold, a below average CET is starting to look no more than 50% likely IMHO.

Yes quite a few days of comparative Warmth coming up it seems as the High moves across Fance bringing South Westerly`s in it`s wake.

Much warmer tonight at 6C -a sign of things to come.

Could be quite bright and warm in the South briefly but i think inevitably it wont last and cloud and dampness will move in later as the High slides South East.

Still the higher temps.will be a pleasant change after the raw chill of recent times.

[Guest North Sea Snow Convection]

Every positive indication that the mild south westerly dirge spell will be thankfully transitory and replaced by colder weather for the last week of the month.

ECM ensembles continue to show a cool off once more from next weekend. UKMO update is supportive of a fairly brief mild spell as well

Edited March 14, 2010 by North Sea Snow Convection

[reef]

Theres quite a spring change-around on the GFS 12z. Temperatures on friday reach 16C before a cold easterly kicks in and two days later maximum temperatures are 1-4C in the North with heavy snow.

Friday, temperatures widely in the teens:

http://www.wetterzentrale.de/pics/Rtavn13817.png

Two days later, strong easterly winds with temperatures close to freezing in the north with heavy snow:

http://www.wetterzentrale.de/pics/Rtavn18017.png

It'll probably be gone in the next run, but it would be fantastic to see after a spring so benign of any extremes last year.

[cooling climate]

Theres quite a spring change-around on the GFS 12z. Temperatures on friday reach 16C before a cold easterly kicks in and two days later maximum temperatures are 1-4C in the North with heavy snow.

Friday, temperatures widely in the teens:

http://www.wetterzen.../Rtavn13817.png

Two days later, strong easterly winds with temperatures close to freezing in the north with heavy snow:

http://www.wetterzen.../Rtavn18017.png

It'll probably be gone in the next run, but it would be fantastic to see after a spring so benign of any extremes last year.

With blocking increasing again to the north the models in the last five or six days have been hinting of

a northerly or a east of north airflow. It may of course amount to nothing but I think its worth keeping

a cautious eye on.

[Frosty.]

The week ahead looks like gradually becoming wetter and breezier but continuing mild with a generally sw'ly flow but the gfs 00z indicates a cold easterly across the north in around a week but no support for that from the ecm although a dip in temps is probable next weekend with a return of overnight frosts but good spells of sunshine too.

[frostyjoe]

Theres quite a spring change-around on the GFS 12z. Temperatures on friday reach 16C before a cold easterly kicks in and two days later maximum temperatures are 1-4C in the North with heavy snow.

Friday, temperatures widely in the teens:

http://www.wetterzen.../Rtavn13817.png

Two days later, strong easterly winds with temperatures close to freezing in the north with heavy snow:

http://www.wetterzen.../Rtavn18017.png

It'll probably be gone in the next run, but it would be fantastic to see after a spring so benign of any extremes last year.

oh how i would love that!!! it would be great to get into wintery weather aswell as summery weather.. i miss the wintery weather! but it will probably be downgraded and downgraded to it eventually gets to 8c or so. but then again if frosty says sunshine itll likely get to 10c like the last high pressure.. somehow i dont think that 3c is possible

Edited March 14, 2010 by frostyjoe

[Ben_Cambs]

oh how i would love that!!! it would be great to get into wintery weather aswell as summery weather.. i miss the wintery weather! but it will probably be downgraded and downgraded to it eventually gets to 8c or so. but then again if frosty says sunshine itll likely get to 10c like the last high pressure.. somehow i dont think that 3c is possible

But in retrospect, mild spells this winter have been gradually downgraded. One time in late Jan/Early Feb the models were showing Bartlett highs, but look what happened afterwards. I agree with CC that we are still at risk of a colder spell from the North or East, due to many factors.

But the 00z OP had little support from its members but if next few runs start to show this then the ens might start to agree more, though probably unlikely. Just a guess though.

Edited March 14, 2010 by Snowman0697

[bluearmy]

at last we have a rise in heights over europe to help begin spring - however, as is mooted above, more chance of another cool spell before months end rather than any sustained spring warmth.

[Thundery wintry showers]

Indeed, the "switch-around" is still there for central & northern districts on the GFS 06Z with plumes of warm air followed by a surge of cold polar air from the north, although southern parts stay in the mild air. ECM has also shown some movement towards that scenario this morning, while UKMO keeps it mild but brings in more of a polar maritime influence for T+120-144- suggesting less mild with sunshine and showers.

So while a mild spell now looks likely, its duration is still up in the air.

[cooling climate]

Indeed, the "switch-around" is still there for central & northern districts on the GFS 06Z with plumes of warm air followed by a surge of cold polar air from the north, although southern parts stay in the mild air. ECM has also shown some movement towards that scenario this morning, while UKMO keeps it mild but brings in more of a polar maritime influence for T+120-144- suggesting less mild with sunshine and showers.

So while a mild spell now looks likely, its duration is still up in the air.

GFS at t168 shows maximum temperatures of only 4 or 5 on the south coast hardly mild.

This of course could be far different come the day but since we are commenting on what

the models show.

[mushymanrob]

not sure i understand some posts here.... missing wintry weather after 3 months of the coldest winter for 30 years?... :unsure: its not gone yet!

todays charts look to me like pretty normal march weather, a right good mix! colder in the northeast, milder in the southwest.. some rain, some sun... smashing spring weather!

[yamkin]

JMA 12Z (13th March) 192h is going for :unsure: Be interesting to see if today's 12Z shows the same.

[Rob]

models hinting that the cold will return with a vengence!

[The PIT]

models hinting that the cold will return with a vengence!

FI stuff and likely to go the way of the last potent northerly. Even in FI land is a very short affair anyway. Although GP did say possible northerlies I wonder what his thoughts are now.

[Guest North Sea Snow Convection]

GFS at t168 shows maximum temperatures of only 4 or 5 on the south coast hardly mild.

This of course could be far different come the day but since we are commenting on what

the models show.

GFS wants to bring in another cold spell.Will the other models pick up on it?

ECM is a big mild outlier towards the end of the latest output. A return to colder conditions seems likely after a relatively brief south westerly mild snap this week.

Edited March 14, 2010 by North Sea Snow Convection

[johnholmes]

JMA 12Z (13th March) 192h is going for Be interesting to see if today's 12Z shows the same.

and how often as JMA validated compared to GFS

ECMWF

UK Met

at this time scale?

[yamkin]

and how often as JMA validated compared to GFS

ECMWF

UK Met

at this time scale?

Not as much, but you never know. It will be interesting to see if JMA continues the trend.