Model Output Discussion

[Wilxy]

hmm, 10c and sunny or 12c and rain. No contest for me.

I think it would be warmer than 12C in the summer from a SW'erly wind. Lets hope that the jet stream will move north soon.

Edited May 8, 2010 by weathercoxy

[SNOW GO]

WOWZERS!! WHAT A WARM UP IF THIS CHART COMES OFF MORE MODEL RUNS NEEDED THOUGH BEFORE WE GRAB THE SHADES AND SUNHAT!!

[Wilxy]

WOWZERS!! WHAT A WARM UP IF THIS CHART COMES OFF MORE MODEL RUNS NEEDED THOUGH BEFORE WE GRAB THE SHADES AND SUNHAT!!

Wow that looks tasty i sware it was looking so cold and dull right through into FI yesterday id love this to happen.

Although, gfs takes it further west so lets wait and see if a trend develops.

[SP1986]

Best burst the bubble now, that ECM scenario is the least likely to happen, even within a range of 600 hours!

A continuation (or from a preferential view, 'a drag') of the conditions we are experiencing currently.

Lots of cool, but mostly dry weather with perhaps some localised frost here and there.

[MP-R]

Wow that looks tasty i sware it was looking so cold and dull right through into FI yesterday id love this to happen.

Although, gfs takes it further west so lets wait and see if a trend develops.

The GFS on the other hand...

http://www.wetterzentrale.de/pics/Rtavn2521.png

Nothing is at all certain just yet. It would be quite good to get some unstable/unsettled weather before the next long anticyclonic spell whether it be cold or warm.

[Thundery wintry showers]

I think it would be warmer than 12C in the summer from a SW'erly wind. Lets hope that the jet stream will move north soon.

It would, but you're not comparing like with like- May is late spring not summer. But there are regional differences across the country- if you add fronts and tropical maritime airmasses to the mix, many western areas would often end up seeing cloud, drizzly rain and 12C, but eastern England would be considerably warmer and might be dry with the odd bit of sunshine especially towards the SE corner.

Regarding the movement of the jetstream, how strong and how far north are important factors. If the jet was to move a little further north than it is now, we'd end up with dull wet weather everywhere from low pressure right on top of the British Isles (although some could copy the infamous phrase "at least it would be milder"!). Significantly further north and it would be a different story, at least down south.

A slight change in the recent model outputs- the Arctic air is reserved for the Midlands northwards while south-eastern areas pick up a drier, cloudier, less cold NE'ly flow. As a result the sunshine and showers scenario (again with possible snow for some on the 11th) would be reserved for Scotland and northern England and possibly the Midlands.

[frostyjoe]

sure we had -1c this morning and its 11c already.

[johnholmes]

Snow caused a days play to be cancelled at either Derbyshire or Yorkshires county cricket grounds. It made front page headlines,here it snowed on June the 1st but did not lay but by the 4th of June the temperature hit 90f here.

at Buxton, admittedly the ground is probably the highest in England around 1,000ft.

In Manchester we went from a max of 6C to 30C in 6 days!

and to make this relevant to the title thread!

There is little to support any major change in the current synoptics way into May at the moment.

Edited May 8, 2010 by johnholmes

[Stormyking]

06Z isn't as bad In FI, looks warmer than it has been showing but yeh its only 1 run and can't trust anything into FI and especially from GFS lol.

Though for the time being still looking pretty chilly/cold for another week or 2 but lets keep our heads up and keep positive further on into the month and towards June

[damianslaw]

Sub 528 dam air moving through much of Scotland on Monday and then crossing into northern england on Tuesday, slowly retreating north again on Wednesday, so three preety cold days for May over Scotland and northern england from Monday to Wednesday. Showers on higher ground in the north will certainly be of snow, and it will feel very wintry indeed. Chance of some localised snow showers on lower ground in NE Scotland Tuesday and into Wednesday especially where any showers are heavy, evaporative cooling will come into play.

The synoptics early next week for the north are nearly but not quite the coldest we can get in early-mid May, if the low pressure anchored itself slightly further se with embedded fronts some very cold conditions for the time of year would result in the north, alas we are going to be in a drier sunnier airstream with only slight trough development.

Southern parts will escape the vagaries of the arctic air, but will still be cool/cold for the time of year.

Signs later next week for the ridge to the west to advect eastwards which may introduce some milder air, but its a long way off and it will only take shortwave development to the NW to kill off the chances of this happening, we could easily be staring at a cold wet affair next week as we see lower heights descend from shortwave development resulting in classic closed low over the country with that ridge staying very robust to the west.

[summer blizzard]

There does seem to be a signal for pressure to build and temperatures to recover after mid-month, though nothing spectacular.

Nevertheless, i do hope the ECWMF comes off, while temperatures would'nt be much above 20C, it would be quite sunny, especially east of the Pennines.

[Thundery wintry showers]

The synoptics early next week for the north are nearly but not quite the coldest we can get in early-mid May, if the low pressure anchored itself slightly further se with embedded fronts some very cold conditions for the time of year would result in the north

Yes, the synoptics for early next week are reminiscent of the second week of May 1995, which although cold and wintry for some (chiefly Scotland + N England) was not quite as cold as the first week of May 1979:

http://www.wetterzentrale.de/archive/ra/1995/Rrea00119950511.gif

http://www.wetterzentrale.de/archive/ra/1979/Rrea00119790503.gif

Like in the May 1995 instance most of the convection and snow potential is likely to be reserved for Scotland and northern England on this occasion. I think the key is more the slackness of the low pressure to the NE, rather than its positioning, resulting in a less pronounced flow and less instability. Embedded fronts are a double-edged thing because if they come too far south and east, they result in modified air, extensive cloud cover, similar daytime maxima, higher overnight minima and rain.

ECMWF shows an evolution that is quite plausible especially for this time of year- a slackening low pressure followed by a build of pressure from the SW, declining shower activity and rising temperatures.

[damianslaw]

Yes, the synoptics for early next week are reminiscent of the second week of May 1995, which although cold and wintry for some (chiefly Scotland + N England) was not quite as cold as the first week of May 1979:

http://www.wetterzentrale.de/archive/ra/1995/Rrea00119950511.gif

http://www.wetterzentrale.de/archive/ra/1979/Rrea00119790503.gif

Like in the May 1995 instance most of the convection and snow potential is likely to be reserved for Scotland and northern England on this occasion. I think the key is more the slackness of the low pressure to the NE, rather than its positioning, resulting in a less pronounced flow and less instability. Embedded fronts are a double-edged thing because if they come too far south and east, they result in modified air, extensive cloud cover, similar daytime maxima, higher overnight minima and rain.

ECMWF shows an evolution that is quite plausible especially for this time of year- a slackening low pressure followed by a build of pressure from the SW, declining shower activity and rising temperatures.

Thanks for putting up those two charts. The FAX chart for Monday and Tuesday more closely resembles the 1979 chart than the 1995 chart. Heights are progged to be lowest to the north east just off the coast of Norway rather than to our south west as is the case in the 1995 chart. What I mean is if those heights to the north east were slightly further south and I should have said west not east they would be able to pull in even less modified arctic air and also probably bring trough or possibly frontal activity at least to the north.

However, you look at it, the progged synoptics for early next week are preety chilly with some lovely pure arctic air for the north of the country - synoptics I'd be relishing if we were in the winter quarter of the year but less so now it is May (have to say though apart from the temps and cold wind, the brilliant sparkling air, chance of brilliant sunny skies and predominant dryness are good compensation - a far superior synoptical pattern than the westerly atlantic mild wet dull muck fest and the cloudy lack lustre eastern airstream).

[Derp Patrol]

i think its going to be intresting to see how long this cold northerly air will last. We usally dont want the alantic to win but i think we could do with it winning if theres gunna be any milder weather.

Yes I agree.. I much prefer south westerlies to easterlies, and sometimes northerlies. At this time of the year, Swerlies usually bring average-above average temperatures to my area from 17-20C with sometimes lots of sun if high pressure is close by, but sunny intervals otherwise. Depends where you live, but this cool weather is absolutely sickening.. the days are just a month and a bit from being at their longest, but I cannot enjoy the sun!

Edited May 8, 2010 by robthefool

[Wilxy]

Intresting that FI is starting to pick up on something a bit warmer and hope this trend continues.

[Stormyking]

I agree too about the Atlantic and i really am starting to kind miss the Atlantic as even Strong winds with Heavy rain is really interesting and also give thunder as well at times if it brings in alot of showers .

Yes Tom FI is showing some pretty decent temperatures and better weather but unfortuenatly it's one run and still in FI . Ah well i am still hopeful for a gradual warm up soon.

[Wilxy]

I agree too about the Atlantic and i really am starting to kind miss the Atlantic as even Strong winds with Heavy rain is really interesting and also give thunder as well at times if it brings in alot of showers .

Yes Tom FI is showing some pretty decent temperatures and better weather but unfortuenatly it's one run and still in FI . Ah well i am still hopeful for a gradual warm up soon.

I know, intresting aswel as ECM picked up on it but yes its only one run, be intresting what the run later shows.

[Thundery wintry showers]

Northerly regimes quite often do see the next change of pattern being a build of pressure to the south, which can then lead to either high pressure over Britain, southerlies (such as in the extreme switch-around in early June 1975 mentioned earlier) or rampant westerlies with a strong jet taking a relatively northerly track. In my long-range forecast I went for a warmer, unsettled third week in view of the above- it will be interesting to see if that verifies.

Showery weather and thunderstorms from the Atlantic are most often associated with polar maritime air, or in some cases returning polar maritime (when low pressure is centred out west and throws up sunshine, showers and thunderstorms from the south and south-west). Those setups generally rely upon the jet being quite weak, because a strong jet will usually mean a succession of fronts moving from west to east bringing extensive cloud cover and bands of light-moderate steady rainfall. May is a time of year when showery "Atlantic" types are relatively common, because the jet tends to be weakest in mid to late spring, though a rampant jet and a stream of frontal depressions are possible at any time of year- take the second halves of Mays 2002 and 2003 for example.

On the other side of the coin I'm not seeing many vibes from the teleconnections experts that we will see any significant pattern change any time soon- and the pattern of mid-Atlantic ridge and northerly/north-easterly winds is a pattern that can recur repeatedly throughout a given month.

[Stormyking]

Northerly regimes quite often do see the next change of pattern being a build of pressure to the south, which can then lead to either high pressure over Britain, southerlies (such as in the extreme switch-around in early June 1975 mentioned earlier) or rampant westerlies with a strong jet taking a relatively northerly track. In my long-range forecast I went for a warmer, unsettled third week in view of the above- it will be interesting to see if that verifies.

Showery weather and thunderstorms from the Atlantic are most often associated with polar maritime air, or in some cases returning polar maritime (when low pressure is centred out west and throws up sunshine, showers and thunderstorms from the south and south-west). Those setups generally rely upon the jet being quite weak, because a strong jet will usually mean a succession of fronts moving from west to east bringing extensive cloud cover and bands of light-moderate steady rainfall. May is a time of year when showery "Atlantic" types are relatively common, because the jet tends to be weakest in mid to late spring, though a rampant jet and a stream of frontal depressions are possible at any time of year- take the second halves of Mays 2002 and 2003 for example.

On the other side of the coin I'm not seeing many vibes from the teleconnections experts that we will see any significant pattern change any time soon- and the pattern of mid-Atlantic ridge and northerly/north-easterly winds is a pattern that can recur repeatedly throughout a given month.

Thanks for that again , another Interesting read up, Im learning more and more by the minute.

Surely the Atlantic will show signs of waking up soon but wonder how long it wil be before it does.

[SP1986]

Just thought I'd say I sent an email to NOAA asking why the GFS is producing incorrect minimum temperature forecasts, I hope if I get an answer it will put it to bed. Once I do get an answer I will stop going on about it

[Milhouse]

After several days away from model watching its good to come back and see things looking a lot better now than when i left. About 5/6 days ago the situation looked awful. We did actually get a couple of very nice days last week but temperatures were definately struggling to get much above 12c. On into next week it looks much the same for the first half but someting of a change later on with signs at last of temperatures recovering.

[Bartlett Low]

Just thought I'd say I sent an email to NOAA asking why the GFS is producing incorrect minimum temperature forecasts, I hope if I get an answer it will put it to bed. Once I do get an answer I will stop going on about it

Well the reply will be an interestng read for sure, Stephen. Its been going on for a quite a while, hasn't it. Anyone who regularly checks the internet (gfs generated) automated forecasts / temps will surely have been scoffing at some of the projections this spring for sure. I've lost count of the times I've seen really low max's projected with wintery precipitation forecasted but in reality its been cool and 10c-13c.

Edited May 8, 2010 by Bartlett Low

[snowlover2009]

I have a good feeling about this summer. Why are people writing it off already? Wasn't it the same in November 2009, when it was extremely wet and then followed by the coldest winter in 30 years???

May 1996, saw one of the coolest or coolest CETs and that led to a fine summer. May 1995 and 97 and 75 had snow in may and had almost the exact pattern for this week, 75 had snow in some parts at the start of June.

I have my own opinion, that cool Mays can favour a decent summer. Here is hoping....

[Bartlett Low]

I have a good feeling about this summer. Why are people writing it off already? Wasn't it the same in November 2009, when it was extremely wet and then followed by the coldest winter in 30 years???

May 1996, saw one of the coolest or coolest CETs and that led to a fine summer. May 1995 and 97 and 75 had snow in may and had almost the exact pattern for this week, 75 had snow in some parts at the start of June.

I have my own opinion, that cool Mays can favour a decent summer. Here is hoping....

Someone will give you the stats that there is no scientific correlation whatsoever.....

[Stormyking]

I have a good feeling about this summer. Why are people writing it off already? Wasn't it the same in November 2009, when it was extremely wet and then followed by the coldest winter in 30 years???

May 1996, saw one of the coolest or coolest CETs and that led to a fine summer. May 1995 and 97 and 75 had snow in may and had almost the exact pattern for this week, 75 had snow in some parts at the start of June.

I have my own opinion, that cool Mays can favour a decent summer. Here is hoping....

This was what I was thinking about, I do remember November being very mild and very wet without anyone knowing that winter was going to turn out the way it did.

I do think summer will sort itself out and reckon it will turn out warm or very warm but it will be a slow progress in my opinion. I would'n remember any of those year as in 1996 and 97 I was too young to remember and 75 I wasn't even born but yeh will have to keep fingers crossed and positive