Model Output Discussion 14th May 2012 Onwards

[Cheshire Freeze]

Crikey, that's a very defeated post considering its 16th May.

No one knows what kind of summer we are heading to, the charts continue to show a cool unsettled spell generally in the reliable.

But if we all go back to basics: these are models (computers) and will almost definetly change output several times as we enter FI.

I Understand your point of 'patience needed' being used on the winter thread and look what winter we had -well very poor for cold and snow lovers.

Fact is - its much easier to achieve in this country warm/very warm spells in summer than it is to achieve cold/very cold spells in winter.

Have patients yes, it's only mid may and the models are already starting to shift to a warmer outlook if unsettled, but it's a start at least.

If we are still in this pattern in mid July then I would be concerned but certainly not on Wednesday 16th May

Not defeatist at all......no-where in that post did I say that summer was over; it hasn't even started yet! In fact, some previous posts of mine over the past month have said that I fully expect a hot period around the end of July/August.

My previous post was alluding to the pattern here and now and its progression over the next 10 days.

[Bottesford]

GFS is looking very good again tonight from mid next week with High pressure taking control in the north first before heading over all the UK

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

I'd say the majority of those charts say to me - chilly and cloudy as they are dominated by NEly feeds. High pressure is around but mostly out to the west which leaves us on the cool side. We need to see high pressure build from the south east if we've any hope of more reliably settled sunny & warm weather.

[I remember Atlantic 252]

GFS is looking very good again tonight from mid next week with High pressure taking control in the north first before heading over all the UK

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

The very last few (deep FI) look ugly to me (south) cold and raw, with snow for Scottish hills only and no warm weather

[ANYWEATHER]

GFS is looking very good again tonight from mid next week with High pressure taking control in the north first before heading over all the UK

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

Gavin. If you had a Pound for every time Gfs proggs High Pressure in FI you would be a very Rich man! Looks to me a very unsettled and at times very cool spell in the near to medium term especially for the Southern half of the Uk although not entirely!!

[PubliusEnigma]

ECM brushes away any suggestion of temps rising to the mid teens this weekend.. Friday sees dull raw easterlies across most of england

with a slow moving or stationary front leading to potentially high rainfall totals and low temps maybe single digits under the heaviest of the rain.

Just across the channel mind you a warm and humid SSW flow keeps almost all of europe in summery weather were its been for what seems

like ages now.

Saturday is a bit of a downgrade on the previous output. Low pressure wobbling around the southern half of the UK, close to SW England and Wales. with North

easterly winds nationwide, and probably leaden skies and light patchy drizzly rain with heavy spells in western parts. Becoming a bit brighter in the far N of Scotland

the extensive cloud cover should prevent a frost on Saturday night though. Crucially the trough that was over Ireland has edged east easing any sense of milder weather

away into the north sea, with some active thundery weather likely over France and Benelux with the benefit of much higher temps here.

Temperatures recovering on Sunday thou to 10oC or 11oC though away from the Far SEast according to the GFS

Very wet indeed in the South on Sunday again according to the Fax chart under attack from the north and the south.

Note how close the warmth is to our shores some 150 miles South east of the SE coast of England.. but no cigar...

[Geordiesnow]

Problem with the GFS charts that even though they eventually hint at a pressure rise, it comes from the wrong direction and whilst the weather may turn drier, there won't be much in the way of heatwaves but for those who might want things to turn drier then the models do hold some promise to some extent, especially the further North you are.

ECM at 144 hours is interesting a little unexpected, the blocking breaks down quicker than the UKMO/GFS and it allows a ridge to form, wait and see how long this run wants to keep that ridge for during the rest of the run.

To me, the outlook at this moment in time does not look to promising but as ever, the detail will change and there is perhaps just chinks of light at the end of the dark tunnel for those who wants a warmer and drier outlook but at this moment in time, its nothing to get carried away with.

[Summer Sun]

ECM brings in high pressure around the same time as GFS

Bring in on I say with those uppers it won't be cold, it would be much warmer than of late

Edited May 16, 2012 by Gavin D

[Snow Shoes]

I think some of the comments posted earlier regarding June-September being "el scorchio" look like more of a "hopecast" to me, as no real evidence to suggest that this summer will be anything other than average (at best)

Edited May 16, 2012 by Snow Shoes

[Summer Sun]

ECM ends less settled but still warm

[Bottesford]

Now that is indeed a nice chart! That would be both sunny & warm. FI as things stand but certainly encouraging!

Not convinced the high will be that far east just yet but fingers & toes crossed...

[Cloud 10]

Good ensemble support for that high pressure on the 12z ECM at 168 hrs.

[PubliusEnigma]

Tuesday shows an interesting COL situation, with the UK sandwiched between two Low pressures with two peripheral ridges

at either end. Under a cool slack North easterly flow, some parts could see some very lively showers, if not thunder and hail storms

in this set up. One to keep an eye on !!

Having a look further out in FI on the GFS. The Northerly just doesn't want to leave the UK. with a Euro Low propping up the high

to our west, although by now, most of west and central Europe will be a lot cooler, more like the UK, but with the trough having moved

away to the east a bit, the wettest weather should be further to east over Germany. We could still be seeing frosts at night as we move

into June.

Edited May 16, 2012 by PubliusEnigma

[johnholmes]

I think that a change in the upper air pattern is now pretty clearly going to occur by the month end. Below are my comments on the charts for the 10 day checks I do every 10 days.

They both continue the theme of a ridge across the the north=Scandinavia to southern Greenland/eastern n america, both also have cut off low in mid atlantic, ec shows 500 flow as s of west with gfs very slack and e in north and about west in south

Good similarities with noaa from last evening

I think its now possible to accept what the upper flow by the last few days of may is going to be a fairly slack affair although just what that will turn out to be is still a bit open

Noaa has a trough(much less pronounced than for some time) to east of uk with other 2 suggesting it to be well west of the uk

Thus the deep upper trough for so long over the UK area is being predicted to change

adding to what I posted this morning having seen both the 6-10 and 8-14 day outputs from NOAA this evening I made these rough notes

Noaa has now turned to the other two and has the trough as they do=west of the uk with a +ve area quite marked now just nne of the uk with a ridge showing just ne of the uk in the 500 flow

With all 3 now showing similar patterns I think its fairly certain that the pattern by about 27-28 may is as shown this evening and this morning

=ridge over n or ne of uk and upper trough to west of uk flow into uk will be south of west at 500mb

So we have quite a shift in pattern from that issued by the 3 outputs on 10 may for 20^th may

with all 3 now showing very similar pattern it is unusual if the actual pattern does not follow the prediction pretty closely

Thursday am=a further refinement suggests as the upper ridge develops just north or NNE of the UK the 500mb flow is going to have an east flow be it south of or north of=a fairly settled countrywide settled spell is perhaps being indicated?

Edited May 17, 2012 by johnholmes

[Anthonyb]

I think some of the comments posted earlier regarding June-September being "el scorchio" look like more of a "hopecast" to me, as no real evidence to suggest that this summer will be anything other than average (at best)

And there is no evidence to say it will be average either.

It's mid May so who knows... In 30 days time we could or may not be in a heat wave.. You just don't know

[Bottesford]

GFS this morning has us under somewhat higher pressure squeezed between two lows to the west and east of us. Looks a bit unusual to me.

Jetstream remaining to our south so I can't see anything that will bring us much warmth.

Before that - chilly north easterlies...

[Summer Sun]

GFS 06z is not as settled as the 12z last night

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

[Buzzit]

While the GFS Ensemble Mean Temp for London remains relatively consistent run to run in FI, there is a much wider divergence between GFS mean, control, and op on the 6z run than of late, with the op being a cool temp outlier in FI.

Edited May 17, 2012 by Buzzit

[Summer Sun]

The met office are now showing a much better outlook for next week with much of the UK seeing some good sunny spells for a time. Temperatures will be below average at first but will probably recover to nearer normal, and may become locally warm during the second half of next week

However, cloud and rain is likely to spread northeastwards into England and Wales later next week and the most likely scenario is for unsettled conditions to persist in these areas for the rest of the month, Other areas are more likely to see more settled, sunnier weather continuing

http://forum.netweat...60#entry2304632

Edited May 17, 2012 by Gavin D

[phil nw.]

Yes signs are there in most outputs for a gradual warming and a drier outlook as we go further into next week.

As some of us have suggested before nothing obvious and dramatic but a steady erosion and warming out of our stubborn upper trough which now seems underway will eventually lead to some warmer air in the mix along with rising pressure.

Details of course are still to be firmed up beyond the weekend- shown by differences in the daily runs for next week.

It may well be the improvements will be less tangible around some eastern coastal districts where a cool Easterly breeze would likely bring cloud and mist along with depressed temperatures,however further west it could well be quite pleasant and sunny from midweek.

Edited May 17, 2012 by phil n.warks.

[The Northern Ramper]

GFS 06z is not as settled as the 12z last night

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

Gavin you have been around here for a while now and as such you know not to follow every run and especially not to compare them.

[phil nw.]

Let`s stick to discussing the model runs please.

Thanks.

[reef]

The GFS 6z looks anything but warm and sunny with high pressure anchored to the north-east and then eventually over Greenland.

The weekend looks pretty unsettled for southern areas with heavy showers, though eastern and north-eastern England look to be overcast and cool with drizzle. Scotland looks to have a much better weekend with some sunshine, but depending on the location of the high eastern areas could well suffer with haar. Temperatures wont be anything special either, with southern areas scraping into the mid-teens.

The best chance of drier sunny weather comes at the start of next week as we're left in a shallow ridge before the low to the south-west makes its way towards us. Again, southern and western areas look the best bet for sunshine and warm temperatures, with 15-18C not out of the question. The east and North east remain under an easterly influence though which suggests again it will be pretty dull and cloudy.

FI then sees high pressure transfer over to Greenland with the main trough over or slightly to the west of the UK. This leaves the us in an unsettled regime with heavy showers and bands of more prolonged rain and temperatures struggling to the mid-teens at best.

Overall, those looking for settled and more importantly warm weather wont get what they ask if this run were to come to fruition.

[Downburst]

Can someone who understand the Teleconnections explain what's going in here? Azores High and Scandi High meeting up and for a time blocking North Atlantic. Surely with all the MJO and ENSO talk so often used here this has to be an inspired instance of something related to that at work? I am amazed at this chart as it's not normal at this time, reminds me of December 2010 period to be honest.

[bluearmy]

the cpc charts seemed to be quite solid on a decent mean block becoming established to the north of the uk 6/14 days and the troughing held over the continent. the fi ops are very keen to retrogress these heights quite quickly and bring in another trough to nw europe. the retrogression has long been the trend in the fi ens but not as quickly as the ops seem to want to do. at least a few better days in the offing later next week. beyond that, who knows. i wouldnt be so sure that the block will hold firm close enough to the uk to deliver more than a few days of better surface conditions. i guess any change in the long established lw pattern will take some time to be modelled correctly. maybe its just fi shannanigans from the ops.

[AWD]

IMO the GFS 12z run is a rather mixed run this evening with a bit of everything.

From now until the start of next week it is a predominantly cloudy picture across most of the UK. Patchy light rain will affect many places at times, with the South seeing the warmest temps.

As next week progresses we start to see a warmer and drier flow inherit. High Pressure settles things down mid week with some rather pleasent weather away from the East Coast.

This is however, not here to stay with pressure starting to drop to the South West as we edge into next weekend, with the South West seeing some rain whilst the north east hang on to the drier conditions.

Into FI and things slowly start turning more unsettled and slightly cooler again across the whole of the UK as the Atlantic edges in from the west, bringing rain and showers to most.

So, we do have a window of opportunity for some decent, more springlike weather next week, but if this run were to verify it wouldnt be here for all too long. However, with other different outcomes being modelled of late for the close of the month, I would be more cautious than ever about FI for now, and just concentrate on the reliable ( ie the next week or so ).