Model Output Discussion 22/07/12 Onwards.

[Summer Sun]

Some lovely FI charts again tonight, makes a change for August

An August heatwave is still possible yet, were overdue a good August now 2003 is the last good one I can remember

Just look how far north the jet stream moves

Edited July 26, 2012 by Summer Sun

[Backtrack]

Some lovely FI charts again tonight, makes a change for August

An August heatwave is still possible yet, were overdue a good August now 2003 is the last good one I can remember

Just look how far north the jet stream moves

Wow Gav, those are some amazing charts! Heat being dragged from the continent. Very warm, high humidity and little cloud anywhere. With the jet stream so far North there's likely to be no spoilers such as trailing fronts from the jet.

I would love them to verify. Although I don't think they will unfortunately, they are only two weeks out, right about the time when I expected the initial burst of heat for August.

Edited July 26, 2012 by Backtrack

[Cheese Rice]

FI wouldn't happen because its the Azores high that is providing the warmth, the current pattern isn't conclusive of such a pattern. As such I'd disregard FI as its far too progressive as one would expect, although you can spot pattern changes from time to time.

[PubliusEnigma]

You can see the scenario playing out from above. The first cold front modelled to arrive is already over the south west and wales and is edging eastwards. Its quite a dry

affair and will serve nothing more than to steer the storms approaching from the front further east as the front clears east before the storms arrive ( which has very much been a pattern of the modern summer over the last years or so ). The storms will beef up over northern France before they change track slightly and move more ENE along the french coast into Benelux for a spectacular display here overnight Fri/Sat. The more active cold front will move south into the UK over night on Fri/Sat bringing the big drop in temps and cloudy skies. So the first front shields us from the thunderstorms, but temps not really falling more than about 7oC or so. Its the second cold front which will bring the drop to below average temps.

[Hathers]

Them charts look amazing. I have never seen the jet stream so far north.

[Sunny Android]

Don't think there would be a breath of wind in the whole of europe here (where are the isobars!!!)

ECM and ENS are very close with this senario too !

[Backtrack]

FI wouldn't happen because its the Azores high that is providing the warmth, the current pattern isn't conclusive of such a pattern. As such I'd disregard FI as its far too progressive as one would expect, although you can spot pattern changes from time to time.

Is it though?

Looks like a link up between the Azores High & a Scandinavian high to me, the latter has been suggested by GP.

[danm]

UKMO showing a relatively fine Monday for most, and possibly dry and fairly warm for the south east on Tuesday:

Edited July 26, 2012 by danm

[reef]

Some lovely FI charts again tonight, makes a change for August

An August heatwave is still possible yet, were overdue a good August now 2003 is the last good one I can remember

Just look how far north the jet stream moves

High pressure doesnt always equal warm, dry and sunny - August 2008 springs to mind.

The chart shown actually shows the high too far north, in this case southern areas are under quite a bit of cloudcover dragged in from the north sea with light rain and drizzle. The temperatures are also below average by day in the high teens, with the warmest areas being in the north and west:

http://www.wetterzentrale.de/pics/Rtavn3843.png

http://www.wetterzentrale.de/pics/Rtavn3844.png

http://www.wetterzentrale.de/pics/Rtavn38417.png

Its T+384 anyway, so as deep into FI as you can get.

[forecaster]

You can see the scenario playing out from above. The first cold front modelled to arrive is already over the south west and wales and is edging eastwards. Its quite a dry

affair and will serve nothing more than to steer the storms approaching from the front further east as the front clears east before the storms arrive ( which has very much been a pattern of the modern summer over the last years or so ). The storms will beef up over northern France before they change track slightly and move more ENE along the french coast into Benelux for a spectacular display here overnight Fri/Sat. The more active cold front will move south into the UK over night on Fri/Sat bringing the big drop in temps and cloudy skies. So the first front shields us from the thunderstorms, but temps not really falling more than about 7oC or so. Its the second cold front which will bring the drop to below average temps.

What surface obs did you use to place the cold front? It's 1830Z now and no change has gone through Cardiff, but that analysis suggests it should have. If it's based only on the satellite imagery, that's a risky business.

[danm]

ECM showing fairly nice weather towards the south and east of the UK early next week, less so further to the north and west. A warm southerly feed is shown for Wednesday:

Monday:

Tuesday:

Wednesday:

Wednesday 850's:

More unsettled for most, however, by Thursday (still some way off though):

[Summer Sun]

High pressure doesnt always equal warm, dry and sunny - August 2008 springs to mind.

The chart shown actually shows the high too far north, in this case southern areas are under quite a bit of cloudcover dragged in from the north sea with light rain and drizzle. The temperatures are also below average by day in the high teens, with the warmest areas being in the north and west:

http://www.wetterzen...s/Rtavn3843.png

http://www.wetterzen...s/Rtavn3844.png

http://www.wetterzen.../Rtavn38417.png

Its T+384 anyway, so as deep into FI as you can get.

Not according to Backtrack, he is suggesting little cloud anywhere and very warm with dry heat

Wow Gav, those are some amazing charts! Heat being dragged from the continent, meaning dry heat. Very warm, high humidity and little cloud anywhere. With the jet stream so far North there's likely to be no spoilers such as trailing fronts from the jet.

I would love them to verify. Although I don't think they will unfortunately, they are only two weeks out, right about the time when I expected the initial burst of heat for August.

[snowfluff]

Not according to Backtrack, he is suggesting little cloud anywhere and very warm with dry heat

Sorry, Cant see how you can get "dry heat,very warm,and HIGH humidity" all at the same time?

Edited July 26, 2012 by snowfluff

[Backtrack]

Sorry, Cant see how you can get "dry heat,very warm,and HIGH humidity" all at the same time?

Well heat is dry regardless of the humidity. It's not as if you step outside on a hot summers day with the sun cracking the flags only to walk back inside soaked.

Continental heat is often dry with low humidity, so I got that a little muddled when I was typing it - my bad.

[mountain shadow]

I cannot see any positivity in the model output tonight for warm and dry. Both ECM and GFS have an upper low encamped on or around our shores from now until T+240.

That can only mean above average rainfall for the end of July and start of August although as ever better towards the south and east.

[OldMetMan]

There is quite a consistency in the model output today for the continuation of the upper low near or over the UK within the reliable timeframe so the likelihood of a return to anything summery such as we have had this week seems remote. The risk of thunderstorms in the next 24 hours seems to be decreasing steadily, even though a trough is still approaching us from the SW, there seems little weather on it, as there does on the cold front associated with the low moving down towards us. I guess there is still a chance for some heat storms in the SE tomorrow but the hot air seems to be getting replaced quite steadily as winds turn more towards the W and NW so the window for this to happen looks small.

I apologise to the Met O for my comments earlier in the week regarding the likely weather for the Olympic Opening Ceremony - clearly they saw the situation as marginal at best and not worthy of any sort of warning so it's time for me to eat humble pie!

However, with LP likely to dominate for some days, we again run into a situation where local high rainfall totals are possible, especially as thickness values are forecast to fall quite a lot so plenty of scope for intense convection.

As I see it at this stage, even at such a long way out, the GFS could well be onto something building pressure NE to Scandinavia, but it will take its time for sure. The upper low may finally sink away to the SE during August, allowing us the benefit of a more long-lasting upper ridge, but I still have a feeling we may have to wait until September to see any persistent dry weather.

Just as a PS, I notice some sharp radar echoes are currently showing up in the Channel with one or two lightning plots but the mid- to upper level flow is veering more to the W, so it's touch and go as to whether they will get to our shores!

Edited July 26, 2012 by OldMetMan

[William of Walworth]

Had a chance to look at some of the links and output properly now, unlike this morning. Models seem broadly in agreement for next week -- more reliable part of timeframe -- which does indeed look like delivering plenty of rain for plenty of places with that slow moving low so close.

I would still maintain that some elements of far-FI output, ie for the following week, still has plenty to play for, but I'm not allowng myself to be as hopeful/optimistic as Gav and Backtrack yet.

Big ifs still attached, but if those GFS FI charts, or anything like them, were to verify, even if only partially, the week starting 6th August could possibly develop very interestingly for summer-preferrers.

But equally possibly, those ideas may well not deliver anything like that .....

Apologies to shed for getting snappy at your post when I saw it early this morning -- it was very early morning when I posted, and I was short of time to take your thoughts in properly ... otr to check anything for myself. Apols.

Old Met Man's more measured thoughts also taken on board as a suitable corrective against any over-optimism for August.... yet!

Edited July 26, 2012 by William of Walworth

[Snowy Easterly]

GFS 18z looks less cool, in fact by midweek it gets warm again, if this were winter we would be having a hissy fit on the downgrade of the northerly

Edited July 26, 2012 by Snowy Easterly

[Cheese Rice]

GFS is already painting August a much better summer month than June or July.

Each run is pushing the troughing further west, as such we are seeing warmer uppers pushing into the UK. As such we finally see a return of average, perhaps slightly above average temperatures across eastern parts of England (Yorkshire Southwards).

I expect subsequent runs to push the trough even further west allowing the whole of the UK to enjoy temperatures around 19-22.c. A big relief across northern UK that has constantly seen temperatures no higher than 16/c.

[A Winter's Tale]

Hello everyone.

This week has seen some pretty hot temperatures in places with maxima into the low 30s in London. Temperatures have also reached 20C up in the north of Scotland too but it looks like a change is on the way.

Tonight should be largely clear away from western Scotland and Ireland and Northern England into NE Scotland. There may be some showers in NE England overnight but the showers should fade away and clear into the north sea. There'll be some light rain moving from the west to bring some rain overnight in western Scotland. Overnight minima of 12-19C. At dawn tomorrow, there should be clear skies and early morning sunshine in most of Northern Ireland, Wales and England but Scotland and the far south of England may remain cloudier with a few sunny intervals and showers are expected around the Channel Coast and in the Scottish Highlands. As the morning moves on, the cold front in Scotland should move eastwards to bring cloud to N Wales and NW England and the south of England may also remain overcast with showers near the SE. Western Scotland should also see some showers too in the cooler airstream. Come lunchtime, eastern areas could be best for sunshine as western areas may be at risk of cloudier skies but some north sea coasts and the far south east again may continue to be cloudy. Into the afternoon and in England, E Wales, Ireland and E Scotland there should be good periods of sunshine with some cloud cover from time to time and again the SE, NI and W Scotland should continue to see showers. Western areas should generally have a cloudier afternoon than elsewhere but sunshine can't be ruled out. Maxima of 17-24C. The rain and showers in the far SE of England should leave the London area for the evening and clear periods amongst the clouds are possible in time for the Opening Ceremony of 2012 London Olympics. Ireland and SW England, Wales, NE England and S and E Scotland could have an evening of sunshine as some showers continue in the NW and cloud cover may move eastwards to bring an overcast spell to some eastern areas of England. For Friday night, generally the bulk of inland England and Wales should have a clear night with the majority of cloud cover in western and northern areas so North Sea coasts may be best for clear skies but the far SE may hold on to the cloud cover of earlier in the day. Minima of 11-15C.

For Ireland, Scotland, Wales, the SW and NW of England it seems that Saturday could indeed by a day of generally cloudy skies with some light rain and showers near the coasts and across Scotland with Northern Ireland perhaps seeing some more persistent rain. The eastern half of England should be best for sunshine on Saturday. A cooler day with maxima of 16-21C. There should be fewer showers on Saturday night with only the coasts at risk. Again, Ireland, Scotland, Wales and Northern England will probably be cloudiest as the south east of England remains best for clear skies. Minima of 10-13C.

Sunday indeed could be a day of more widespread shower activity across the British Isles and Northern Ireland and Shetland could see some more persistent rain. There could be more cloud cover in southern and eastern areas of Sunday and some brightness is possible from time to time in northern and western areas inbetween the showers but I'd say that the NE of England and some inland parts of England could be favourable for good periods of sunshine. Maxima could be 15-19C. Most of the showers should have died away by Sunday night with only the coastal regions of the far NW at risk of a few showers. Clear skies should be more widespread with Eastern Scotland and England looking best for clear skies and the thickest of the cloud cover should be restricted to western coasts. Minima quite cool at 9-11C.

Monday at the moment looks like a day with little in the way of long periods of sunshine with a gererally cloudy outlook for the British Isles but sunny patches are likely in places. Northern Scotland could have a wet day with light rain and showers but some drier periods are possible. Some light rain could also reach Southern Ireland. Maxima of 15-20C. Monday night also looks cloudy for most of us but some clear skies are possible in Scotland, especially near the North Sea. For parts of Ireland and Wales, the SW, parts of the NW and into central areas of England the models are showing some persistent rain moving in from the Atlantic. Minima of 9-14C.

I'm afraid that low pressure will become an influence again and the models are showing a return to heights over Greenland but it doesn't neccessarily mean that we'll see the same cool, dull and very wet conditions of June and early July. Showery conditions look likely in the next few days with a few fronts from time to time and there'll be a mixture of cloud cover and clear spells spread out across the British Isles. And in the chart shown below, you can get southerly winds if the positioning of depressions are favourable.

Although we are back to having heights to our NW and low pressure near/over the British Isles, following the model output for the near future (say 3-6 days) and you'll have an idea as to what the overall picture is and you may find that there could be a few decent days of weather that you can make out of this outlook. And also, having a regular glimpse to longer outlook may help to give you clues to whether the theme of the present/near future may continue and you can come up with your own interpertations to the outlook and possibly pin-point types of weather/synoptic for a certain time-frame for the British Isles.

[shedhead]

Not as bad as June is about the only +ive spin I can put on the overnight runs, with LP shown to remain in charge throughout the first week of Aug and if GFS is to be believed, deep into week 2 as well. As Summer so far has shown a deep, persistent trough pattern is difficult to shift, hence charts like this well into FI.

Edited July 27, 2012 by shedhead

[minus 9]

Why shedhead do you always find the worst charts of any given model run. Negative or what.

[legritter]

morn all ,going by current charts its looking like a very mixed 10days coming up with plenty of different synoptics on offer for all .low pressure over or to our west or north ,and even the possibility of later next week seeing some warm and humid air being pulled into the mix ,this with low pressure and still a strong sun will present some difficulties with local forecastingas the public will be involved with many outdoor events .seeing we are a nation obsessed with the weather it would be nice this evening to see MICHAEL FISH along with a few other ex bbc and tel presenters ,do a turn at the olympics, after all its the best of british and the weather is always the first on most peoples mind ,i hope they dont forget our CAROL KIRKWOOD AS HER SMILE IS AS GOOD AS THE SUN AFTER A WET DAY ,OF TO SEE IF CHART AS UPDATED CHEERS

[Robbie Garrett]

After a pretty successful July 2012 forecast. forum.netweather.tv/blog/316/entry-4429-summer-2012-long-range-forecast-v20-july-2012/

Here is August 2012.

Summary - With the NAO state forecast to head into a more negative state, again going neutral - August will be a pretty tough month to forecast. Indications are that there may be a settled period, but not until after another unsettled spell. Enjoy!!

Click here!!

Edited July 27, 2012 by Robbie Garrett

[shedhead]

After a pretty successful July 2012 forecast. forum.netweather.tv/blog/316/entry-4429-summer-2012-long-range-forecast-v20-july-2012/

Here is August 2012.

Summary - With the NAO state forecast to head into a more negative state, again going neutral - August will be a pretty tough month to forecast.Indications are that there may be a settled period, but not after another unsettled spell. Enjoy!!

Click here!!

Do you mean, not until after??