Model Output Discussion 14th May 2012 Onwards

[phil nw.]

I take it this is the answer to the long-range models showing the greenland block being replaced by low pressure?

Hi Robbie,

I am guessing you are refering to the CFS charts?

If so i can`t really comment as i don`t use them.I try to stick to the tools from the NOAA site-ie the 500hPa charts up to 2 weeks at most and of course daily outputs and the mean hts etc.I try and look for trends in those although as John H has commented in the past the weather can still prove us wrong at even closer ranges.

For this reason i tend to leave those longer range charts alone.

Edited May 29, 2012 by phil n.warks.

[Gavin P]

Useful video by Gavin P (check out his site for his latest vids: http://gavsweathervids.com/) about the models for the next two weeks. Plus today's and tomorrow's thundery potential. Indeed, as is shown on the models, such as the 0Z ECMWF, those Lows out to the West seem eager to spring back into action increasing the chanes of disturbed weather for most (though changes regarding the Lows' positions could still occur).

Hey, thanks for posting Alex.

[Robbie Garrett]

Hi Robbie,

I am guessing you are refering to the CFS charts?

If so i can`t really comment as i don`t use them.I try to stick to the tools from the NOAA site-ie the 500hPa charts up to 2 weeks at most and of course daily outputs and the mean hts etc.I try and look for trends in those although as John H has commented in the past the weather can still prove us wrong at even closer ranges.

For this reason i tend to leave those longer range charts alone.

Hello,

That's fine, just making a cross reference that you can see the northern blocking (which is likely to be Iceland/Greenland block), in the medium range looking like the following '"with hints of a retrogressive pattern as i suggested earlier-those Northern heights becoming less of an influence with time to be replaced by low pressure to our immediate north.A more conventional UK Summer pattern.""

CFS was yesterday showing this, haven't looked at todays but it was consistently showing for the last week or two (with different synoptic's thereafter) that high pressure was to get flattened out by low pressure, with high pressure building over the UK with it centralised over Europe.

I guess the most likely pattern to develop over the next few weeks is likely to be southwesterly dominated, with the occasional southerly. Perhaps a quite thunder summer outlook? Depending on if the azores wants to build a slack high pressure into Europe?

UK Outlook for Wednesday 13 Jun 2012 to Wednesday 27 Jun 2012:

Indications are that most areas will be rather changeable with periods of showers or longer spells of rain interspersed with drier and brighter interludes. There are some signs that southern areas may see more in the way of unsettled conditions, especially from the middle of June. Temperatures are most likely to be near or above the seasonal average, but perhaps cooler in the south.

And having read the Metoffice update, I guess if the south had unsettled conditions the UK would have a north/south split with High Pressure across the north likely centered around Iceland instead of Greenland, with the chance that it could sink??? When was the last time a Summer Started off with more settled conditions towards the North??

Cheers.

[The Northern Ramper]

The met have been saying this for a while now.

[TonyH]

After a cool end to the week with maxima of 12-15C likely on Friday for many of us, daytime temperatures will most likely rise to near normal by Monday, with highs of 15-18C, although nights will remain chilly.

With charts like these and 10c uppers still in the SW really can't see it being that cool for central and western parts. More like 18-20c I would imagine here.

In fact uppers for the south and west are lower on Monday:

GFS now supports this showing appreciably higher maxima for Friday:

Edited May 29, 2012 by TonyH

[damianslaw]

A slow transition to significantly cooler and generally more changeable conditions is being shown by all the models tonight.

ECM and UKMO show the atlantic trough making inroads into western parts early next week, as we see heights ridge SW out of Greenland and the scandi trough languishes in situ. GFS is also painting a similiar synoptic pattern though less bullish in how quickly the trough arrives.

Its a complex set up, the atlantic doesn't look as if it has much oomph to it, and the jetstream isn't on a crash course for southern europe, these factors will make it much easier for the azores high to ridge NE behind the trough, but much will depend on the position of heights to our NW. We could end up with the trough stuck in limbo over the country - much like previous summers, but this may only be a temporary affair. ENSO is neutral at the moment, I don't claim to know how ENSO behaves, but I understand neutral ENSO state favours mid atlantic blocking?

In overview - a change to more typical early June fayre, no washout, but also no heatwave, to expect the conditions of the last 10 days to last another 10 days would be unprecedented for this time of year...

[William of Walworth]

We're pretty used to listening to the 'Winter's over before it starts' soothsayers, but those who frequent the MDT across all seasons and all weathers can normally be relied upon to be a little less melodramatic! OK things are set to go downhill bigtime regarding temps across the rest of this week and yes the holiday weekend does look cool/very cool and a little unsettled, but even come the end of it we'll still be in the week 1 of a 13 week Summer. Again I know it's tempting to assume the pattern will set up much as across the last 3 or 4 summers, especially as the northern blocking seems determined to remain in place, but as the last week or so has shown things can change both quickly and dramatically.

Thanks for this highly common-sensiblist post shedhead, I'm also appreciating the much more objective recent contributions from phil.n.warks and Robbie Garrett, and that's not just about my own hopecasting from them. Their suggestions allow room for what we used to think of a more typical summer mix. HP ridging with some Lows too, whereas the way some others have determined that the first part of June (at least!) is a near-writeoff, just looks over determinist to me, not to say doom mongering and selectively pessimistic!.

Matters even for the upcoming weekend still don't seem fully nailed on yet. I'm seeing possible signals for a less powerful Northerly blast than in earlier runs. By no means a heatwave or anything like that, but could be pleasant enough in places, and still not many signs at least not at first?? of a washout.

Beyond that, well it is FI. But to tentatively guess, for me Northern blocking strong enough to prompt a rageingly powerful string of Lows from the Atlantic straight at us has been our fate in some summers, but I'm so far/for now having fewer fears about that than I've had in some recent summers, notoriously difficult though it always is to read into FI and beyond.

Edited May 29, 2012 by William of Walworth

[johnholmes]

quick notes from my 500mb anomaly checks this evening that take us into the first 7-15 days of June.

It would seem to suggest no 'Flaming June' in this time scale!

Tue 29 may

Ec-gfs

Ec now has one closed low centre just nw of uk with ridge beyond Greenland so flow is s of west with fairly low contour values

Gfs ridge not that different area but with two cut off lows not that different to its idea yesterday main one to ne of uk with less marked one well out in atlantic

Neither suggest more than unsettled

Noaa

All 3 today are of a similar idea

Similar to mon, +ve arctic area nw of Greenland, -ve and associated trough uk area from ne of uk to sw of uk for –ve area, flow is just s of west

[Robbie Garrett]

Thanks for this highly common-sensiblist post shedhead, I'm also appreciating the much more objective recent contributions from phil.n.warks and Robbie Garrett, and that's not just about my own hopecasting from them. Their suggestions allow room for what we used to think of a more typical summer mix. HP ridging with some Lows too, whereas the way some others have determined that the first part of June (at least!) is a near-writeoff, just looks over determinist to me, not to say doom mongering and selectively pessimistic!.

Matters even for the upcoming weekend still don't seem fully nailed on yet. I'm seeing possible signals for a less powerful Northerly blast than in earlier runs. By no means a heatwave or anything like that, but could be pleasant enough in places, and still not many signs at least not at first?? of a washout.

Beyond that, well it is FI. But to tentatively guess, for me Northern blocking strong enough to prompt a rageingly powerful string of Lows from the Atlantic straight at us has been our fate in some summers, but I'm so far/for now having fewer fears about that than I've had in some recent summers, notoriously difficult though it always is to read into FI and beyond.

Just had a look at the NAO, it does indeed point to Northern blocking. Everything that I am looking at points to June Atlantic onslaught, in terms of wetter weather, but temperatures don't look that bad in the more medium term. There seems to be some sort of rise in the NAO, from my view there looks to be a chance of another week or two of warmer weather, probably in the next few weeks, if the northern block can sink somewhat, and links up with the Azores, budging that low pressure towards Iceland way we may be in for a good chance of round 2 of what we have just had. But I am rather skeptic if this could occur, in the near distance... it probably wont show up till a few days (so no point looking at FI on the GFS etc) - the best bet would probably be wait it out game.

But to be fair look at the spell we have just had, I don't think anyone can complain. It was inch perfect.

Mixed bag, pretty much a standard British Summer is on the cards. So at least we can count ourselves lucky that we may indeed get some better settled spells, interspersed with mega-unsettled spells. But if anyone is for 3-6 weeks of wall to wall sunshine go have a look at www.firstchoice.co.uk I am sure there are plenty of opportunistic places there. (nobody quote me on this in September please lol)

I am not personally writing off June, but the outlook doesn't look good. Still July, August, September and October for Summery weather. (Sunny/warm, Clear Skies, fresh air)

Edited May 29, 2012 by Robbie Garrett

[lorenzo]

I think the last week or so has exceeded expectations, pretty similar to when we get a real pasting with snow, everyone wants more!

Special set up ensued, even by high summer, the spell of heat and perfection with the HP was astonishing.

Looking ahead I agree that we have a mixed bag of solutions. For something different and looking at where the sun and seasonal warmth may pull through, found that this is now on the ECM sample run, ( changes daily- well did a few months ago.). Not seen this cloud graphic supplied before.

Image not posted due to copyright. As per 12z Saturday looks like a fine day for much of the UK, clear skies.

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/high%2C_medium_and_low_cloud_cover!84!Europe!cloud!pop!od!oper!w_clouds!2012052912!!/

[William of Walworth]

Not much in that one for summer-hopers in June, Robbie, but thanks for it anyway.

At least leaves some scope for shortish? interludes of finer more settled-ish weather at times, inbetween the Atlantic attacking us. And plenty of room for uncertainty, still, which is why wait and hope is all us sunshine lovers can do for the moment.

<Trying not to foucs on my main holiday aroudn the weekend of the 24th -- still much too far ahead!>

[Radiating Dendrite]

In regards to Saturday, I am surprised to see such low temps being predicted (13c in Leeds for example). Surely with clear skies and a strong sun, we could be looking at temps getting up to around the 17/18c mark??

The 850hpa temps have improved on recent runs, and the SW could now be in for quite a warm day (low 20s) on Saturday.

[shedhead]

In regards to Saturday, I am surprised to see such low temps being predicted (13c in Leeds for example). Surely with clear skies and a strong sun, we could be looking at temps getting up to around the 17/18c mark??

The 850hpa temps have improved on recent runs, and the SW could now be in for quite a warm day (low 20s) on Saturday.

Indeed, as far as southern and particularly southwestern parts of the country are concerned the charts are taking on more of a winter type look, at least in so much as the closer we get to an event, the further and further north the colder air gets held. If this trend continues we may well see a fairly warm start to the holiday weekend down here, the danger being when the two air masses do engage it could deliver a wet spell for Sun/Mon.

Edited May 30, 2012 by shedhead

[tinybill]

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=6

no change from yesterday even deep f1 its still nasty is it going to be a nice wet british olympics in july !!!!

[shedhead]

http://www.meteociel...hp?mode=2&ech=6

no change from yesterday even deep f1 its still nasty is it going to be a nice wet british olympics in july !!!!

Even if that chart for June 15th were to verify, I'm not sure what bearing it's likely to have on events between 27th July - 12th Aug. Perhaps you'd be kind enough to enlighten us all?

[Thundery wintry showers]

The Jubilee weekend will most likely start off with sunny intervals, broken cloud and only isolated showers during Saturday and Sunday, but temperatures will be variable, ranging from near average in the west and south to somewhat below in eastern Scotland and NE England with the winds coming in off the North Sea. There is slight potential for some frontal rain to come into the south on Sunday but I reckon that it will probably only graze the south coast. Monday looks like having sunshine and showers for most, but some coastal areas, including the Tyne and Wear coast, will probably stay convection-free due to onshore winds.

The GFS and UKMO outputs from Tuesday onwards look scarily reminiscent of recent summers with the southerly tracking jet speeding up somewhat, but ECMWF has frequent ridges of high pressure into central Europe promoting a warmer cyclonic south-westerly type over the British Isles. I'll wait until tonight's runs before reaching a conclusion on the more likely outcome.

[Summer Sun]

Eary outlook for the bank holiday weekend suggest's it will be cooler than of late but only a low chance of it been wet, there will also be sunny spells at times

[johnholmes]

Even if that chart for June 15th were to verify, I'm not sure what bearing it's likely to have on events between 27th July - 12th Aug. Perhaps you'd be kind enough to enlighten us all?

one has to agree with your assessment of that post.

Its hard to decide if some, and there are a number on Net Weather, simply are not too well up in meteorology or love trying to wind folk up?

[Downburst]

The long Range Forecast was supposed to be updated towards end of this month. Does anyone know when it will be posted? Thanks

[Methuselah]

The long Range Forecast was supposed to be updated towards end of this month. Does anyone know when it will be posted? Thanks

I believe that it'll be posted at the end of the month.

[Robbie Garrett]

Not much in that one for summer-hopers in June, Robbie, but thanks for it anyway.

At least leaves some scope for shortish? interludes of finer more settled-ish weather at times, inbetween the Atlantic attacking us. And plenty of room for uncertainty, still, which is why wait and hope is all us sunshine lovers can do for the moment.

<Trying not to foucs on my main holiday aroudn the weekend of the 24th -- still much too far ahead!>

I can see a plume happening late June/Early July at latest and this is not hope-casting but the long range models have been very brave regarding a settled period in July, followed by some fairly unsettled weather, followed by a fairly decent August/September spell. I think personally, the weather may well match 2005/2006 for this Summer, with a fairly neutral NAO come end of June throughout July, August and September, with a good chance of it going negative in time for Winter.

In essence the following could probably come to fruition for June looking at Models.

A typical summer month, characterised by some very warm or hot weather interspersed with some very wet and thundery weather.

I can understand that we are going to have a fairly negative NAO, but it's only a forecast, I can see it heading back to neutral by mid June at latest, and this is backed by the CFS.

It's showing it for Mid July, but I suspect we may get somewhere nearer this late June.

Just to add, it looks highly likely that June 2012 may be scripted to this, as this is what the long-range Models are showing. http://www.metoffice.gov.uk/climate/uk/2005/june.html

Edited May 30, 2012 by Robbie Garrett

[Mapantz]

Models showing it to be pretty wet in the south on Sunday. On Monday, the BBC were saying 'Dry jubilee weekend' I thought at the time that it was a bit outlandish of them to say that.

[Summer Sun]

I believe that it'll be posted at the end of the month.

Well there isn't long now tomorrow is the last day of spring

[johnholmes]

A pdf with some ideas on the various factors that may influence the start of summer and my ideas on what this may mean over the next 3 weeks

Forecasting for early-mid june.pdf

Edited May 30, 2012 by johnholmes

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

Looking like a cold start to the new year