Model Output Discussion - 15th April Onwards

[damianslaw]

Anys suggestion of the trough backing westwards towards the end of the month have been fundamentally cast aside in todays models, the prospects of more of the same right through to the end of the month now look very high. Indeed the models are remarkably consistent in their outputs right through the end of the month. Also the BBC the other day unusually said the rest of the month would remain very unsettled - very rare for them to stick their neck out on broadcast, the Met Office must be very confident of the current pattern holding suit until at least the end of the month.

Models are showing a greenland high forming next week with the slow moving trough stuck across the country, certainly no sign of any warm up for the foreseeable future, dissapointing, but it is only April and this is the time of the year when cold northerlies and northeasterlies and chilly cyclonic conditions often wage battle with the atlantic and very often win. This April could turn out to be a month devoid of southwesterlies, it has so far been a very 'northerly' month. Some of the synoptical output for next week is very similiar to that of late November 2010.

April 2012 is certainly turning into one of the most unsettled and chilly Aprils' in a long while.. complete opposite of the likes of 2007 and 2011,the 6 week dry warm period from mid Feb-late March came far far too early..a bit like last years warm dry April and start to May which precedeed 3-4 months of mostly unsettled weather.. mother nature always balances herself out..

[SP1986]

18z no change.. unsettled and cool. Not much more to be said really. FI showing it's usually variation with high pressure and some warmth, but really I don't even buy the idea of it, nevermind the literal model portrayal.

I'm not finding these synoptics that interesting, but if they could produce interesting weather around here, then personally I would hold the pattern in higher regard. It's not very interesting at all locally, synoptically or in terms of weather. (In general breezy, cloud, a little sunshine, nothing much in the way of showers)

[stewfox]

I was quite interested as to why and how, but I take it this is part of the patterns we are seeing in the Nern Hemisphere. I take it that any major pattern change, such as warmer temperatures and high pressure should not be taken much into till at least +168 period.

CFS now indicating a very wet may, with temperatures closely at 12/14*C is thats below average right?? It's also indicating a very unsettled June/July and late July, Early August looks very confusing.... something to watch that's for sure. But to be fair, it would not surprise me if this was the case.

I remember someone posting how this year has panned it is very similar to the year, June and July was severe washout (Monsoon) conditions. What year was it??

Wet weather continues well into June, I take it a Scandinavian high in June???

And until the Jestream tracks north, the idea of Summer here we come is not going to happen!!

I would be very surprised if FI in the summer is now taken as 3 months, cf T72 somtimes in the winter, not prepared to write the summer of just yet in mid April.

Edited April 20, 2012 by stewfox

[SP1986]

The difference between the UK and Europe is quite staggering on the latest outputs. Europe will consistently get warm weather with only the UK getting colder weather, It's becoming the norm too, with UK in the past few years often standing alone at least 10C cooler than anywhere else on the continent. No chance of change either for the foreseeable future.

For those wanting warmth these runs do pose a severe set back, but for those wanting a cold scenario, the charts are as good as it gets with persistent very cool weather dominating for the next 2 weeks most likely.

It's not wise to write off summer based on current synoptics I agree, but we should keep it in our minds that it is a very realistic possibility that this summer will, in fact, be, a write off.

[Scorcher]

The difference between the UK and Europe is quite staggering on the latest outputs. Europe will consistently get warm weather with only the UK getting colder weather, It's becoming the norm too, with UK in the past few years often standing alone at least 10C cooler than anywhere else on the continent. No chance of change either for the foreseeable future.

This is a sweeping statement if I ever saw one. How then do you explain the spell in March in which Scotland was warmer than much of the continent? What you say is generally not true in my experience, yes the continent is often warmer in the summer months but this is a major exaggeration.

GFS and ECM both want to bring warm air into Central Europe in just over a week's time but it seems to only really affect Germany to any great extent, with much of France missing out on the heat as well as the UK, although I think things will become slightly warmer in the UK too.

Edited April 20, 2012 by Scorcher

[Summer Sun]

GFS 06z is showing some spring like temperatures for early May this morning, at least it would be better than what we have now

[Robbie Garrett]

No not writing it off, but the facts and figures are there and supportive of a very unsettled period. Considering how settled the past 14 months have been. Especially for the most southern parts of England, if ENSO and NINA conditions do have a delayed effect. Then the CFS is right in forecasting an unsettled period till at least the latter parts of July 2012. Let's see what the trough does in the next few days/weeks... as the tedency may be for it to move west, which would allow greatly for a humid but thundery unsettled start to Summer 2012.

I have repeatedly mentioned that I am not writing Summer off, just the fact that very high temperatures 33+ would likely not be possible because of the synoptic setup, would likely mean plenty of cooling off with severe thunderstorms.

The CFS looked very flirtacious with two options, a mid Atlantic ridge (azores high) keeping us dry but because the jet is so far south, I don't think this will happen, so that gives the second option more chance to run it's money and that's northern blocking in the form of a belt of high pressure over Scandinavia and Greenland, which is quite credible because the synoptics are delivering this.

Personally, I think the scandinavian ridge if it does indeed form, may sink into Europe come June/July and as the jet gets cut off by the Azores High (August time) there will be a low pressure area stuck in the eastern atlantic to the south west of the Bay of Biscay and we may well get a Summer around about that time period.

However just had a brief overlook of the GFS, and it is indicating a change from cooler/colder conditions to some warmer conditions. But still remaining unsettled... and the trough is moving (coming cut off from the west) but people have said not till +168 can we believe it's happening, and that the rest of the run is conclusive to a pattern change.

So no, not writing Summer off just merely pointing out that unsettled doesn't necessarily mean a crap Summer, it could mean a clear, warm, humid and thundery one...

Edited April 20, 2012 by Robbie Garrett

[Polar Maritime]

The difference between the UK and Europe is quite staggering on the latest outputs. Europe will consistently get warm weather with only the UK getting colder weather, It's becoming the norm too, with UK in the past few years often standing alone at least 10C cooler than anywhere else on the continent. No chance of change either for the foreseeable future.

For those wanting warmth these runs do pose a severe set back, but for those wanting a cold scenario, the charts are as good as it gets with persistent very cool weather dominating for the next 2 weeks most likely.

It's not wise to write off summer based on current synoptics I agree, but we should keep it in our minds that it is a very realistic possibility that this summer will, in fact, be, a write off.

I agree something is effecting the Jet Stream, as the last 4 years have been a stark difference regarding the climate in Northern latitudes.

I do belive solar activity is the big player in this. http://iopscience.iop.org/1748-9326/5/2/021001

[Scorcher]

GFS 06z is showing some spring like temperatures for early May this morning, at least it would be better than what we have now

Yes Gavin definitely still some hope for warm weather fans, again I think people are writing this off too quickly, similar to how many were convinced high pressure would re-establish itself quickly at the beginning of April. Not settled my any means but we may at least lose the below average temperatures for a while.

[Polar Maritime]

Yes Gavin definitely still some hope for warm weather fans, again I think people are writing this off too quickly, similar to how many were convinced high pressure would re-establish itself quickly at the beginning of April. Not settled my any means but we may at least lose the below average temperatures for a while.

All down to cloud cover off the North sea, with a nagging N/E wind it want feel that warm unless the cloud clears.

Dont get me wrong i want a hot summer to, It's just not synopicly looking good atm.

Edited April 20, 2012 by Polar Maritime

[Anthonyb]

Reading through posts I find it hilarious that on 20th April I read

" the summer sypnotics look like being a wash out"

"let's write off summer 2012"

" based on the models a hot summer does not look on the cards"

Do me a favour - since when is FI 4 months away!!!

Just because we are having a similar April to the washout summer does not mean it will follow suit... Utter nonsense.

If we were in August making these bold statements about what winter will hold I'm pretty sure you would all be slated or laughed at so what the hell is different here.

Although I do find it highly amusing that you all seem so confindent about August 2012 weather....

Of course we may have a rubbish summer and I know you are all reading what the models look like right now, come this time next month they could change/they may not 50/50

I'll say it again it's 20th April not 20th July.

Edited April 20, 2012 by Anthonyb

[reef]

How about we talk about what the models are showing and not what we think might happen in the next 3 months? I would bet with a lot of confidence that no-one can even predict over a week away with any accuracy right now, especially so with the current flabby setup.

[Thundery wintry showers]

Indeed, there is currently a fair amount of uncertainty over the track of the frontal system on Monday/Tuesday for instance, which has been revised further south in the last couple of runs. If it is revised much further south, then most of us will be left with a continuation of the sunshine-and-showers regime through to at least Tuesday, but a toning up would result in cloudy wet conditions for most on Monday and possibly Tuesday too. The odds, in my view, currently favour a rather wet Monday in the south and brighter showery weather in Scotland and northern England (though possible low cloud near North Sea coasts) and then a showery day for most on Tuesday.

There is growing model agreement on a rather stagnant setup towards the end of the week. What we often get from this is a belt of north to north-easterly winds to the north (associated with a mix of sun and scattered wintry showers), a returning polar maritime airmass to the south (with sunshine and thundery showers) and a slow-moving rain belt marking the boundary between the two airmasses. However on this occasion we have the added complication that if low pressure ends up further west than currently progged, then continental air may filter in from the south-east, in which case the situation may get particularly messy.

[AWD]

According to Matt Hugo, who has access to the EC 32 dayer, this mornings run basically suggested a brief warmer and settled spell in early May, before returning to cooler and more unsettled conditions again Mid May!

Perhaps what the GFS has been showing in FI lately is on the right track! Growing support for some warmer temps in early May, if only briefly!

[Summer Sun]

GFS 12z continues to build high pressure building as we leave April and enter May

Hopefully the end is in sight to this cloudy wet weather and we can finally enjoy some proper spring like weather

Edited April 20, 2012 by Gavin D

[Alex]

Doubt it will last unless upstream patterns start to change. Really we need GP to tell us what would Kickstart a summery period of weather which seems so far away at the moment.

[rob48]

GFS 12z continues to build high pressure building as we leave April and enter May

<snip>

Hopefully the end is in sight to this cloudy wet weather and we can finally enjoy some proper spring like weather

What we have at the moment is "proper spring like weather".

Very nice it is, too.

Edited April 20, 2012 by Bottesford
Removed long quote

[Summer Sun]

Rainfall totals are shown to drop very low from late April and early May in the East in line with GFS 12z building high pressure, next week should see some useful totals again

Edited April 20, 2012 by Gavin D

[Uncle_Barty]

I always say that you can't tell what the weather will be doing several weeks hence, but on the other hand I know where SP1986 is coming from on this occasion...

Watching the models in recent days has brought that sinking feeling of deja vu from recent summers, with blocking out west stretching towards Greenland and a persisent upper trough over or just to the east of the UK.

It is also true that recent patterns have stuck around for 3-4+ months at a time, notably the pattern that lasted from last September through the autumn.

If the pattern we have seen recently establish remains for a similar period then it will write off the bulk of summer as we sit here and watch more eastern parts of Europe bake while we see the "cancelled" banners appear across the posters of planned outdoor events again and again up and down the country.

GFS hinting at HP forming to the N of the UK by days 9-10 but I would have low confidence in thast at the moment.

[Robbie Garrett]

Coldest May is 6-800 miles North east of us according to GFS FI. If the models are overdoing this high to our north, then I Wouldn't be surprised the trough staying put, any any high pressure that builds sticks to Greenland, and the trough sinking further south. -10 uppers in may would be nice.

[No Balls Like Snow Balls]

GFS 12z continues to build high pressure building as we leave April and enter May

Hopefully the end is in sight to this cloudy wet weather and we can finally enjoy some proper spring like weather

I thought we were already enjoying some proper spring weather in the form of April showers.

[Summer Sun]

ECM builds pressure for a short time before low pressure returns

Edited April 20, 2012 by Paul

[damianslaw]

Not much to add - models continue to paint a very unsettled picture as we end the month and enter May. Upstream pattern well into May suggests no immediate change in the current set up. We may see a spell of drier slightly more settled weather early in May, but there are no indications of the trough suddenly moving eastwards or westwards anytime soon.

This is a very stubborn set up, synoptics which ruled the roost during the last 5 summers... mmm a common theme is developing here..though this year these synoptics have arrived much earlier rather than during May.

We saw superb quite exceptional synoptics in March... lets hope the last week of March 2012 doesn't end up being the equivalent of last years easter week, which for many especially in the north brought the best conditions of the year in terms of sunshine, dry very warm weather.

[Glacier Point]

Doubt it will last unless upstream patterns start to change. Really we need GP to tell us what would Kickstart a summery period of weather which seems so far away at the moment.

...some limited suggestion here that with angular momentum falling back to a more Nina like pattern, the ridge might build over the top of the trough week 2-3 settling things down finally for the north of the UK to start, these more settled conditions heading southward over time.

CFS week 3 & 4 height anomalies:

http://origin.cpc.ncep.noaa.gov/products/people/sweaver/cfs_fcst/images1/wk3.wk4_20120419.z500.gif

[bluearmy]

suggestions from noa cpc that although we remain under the influence of the trough (centred over n iberia), the 552 dam mean thickness lifts out to the north of the uk days 10/14 which would allow the temps to recover, maybe to a little above average with a continental drift. staying fairly unsettled in general though. (better the further nw you are). i see no consistent trend beyond the sinking south of the trough centre week 2.