Wednesday could see a severe spell of weather, depending on the extent to which convective activity occurs.

After all, a high-moisture airmass is predicted to advect northward from the continent, potentially at low levels, in which case it could become very unstable.

As the intensifying low pressure develops and moves close to the UK, this currently looks sufficient to create strong vertical wind shear, which is a key ingredient for organised convective weather that could be severe in nature.

GFS looks to be producing a MCS (mesoscale convective system) from this potential. I'm not sure about ECM but it does bring a lot of rain to the west in particular as NSSC has pointed out for us.

Obviously UKMO is showing a setup that would be far less threatening so... we'll see. Having read many accounts of what this kind of system can do in the USA, my imagination is running wild, but I'm not expecting anything like as intense as those events can sometimes be!

Originally Posted by: North Sea Snow Convection

Wednesday continues to threaten to be a horror show - most especially though the GFS which keeps insisting on ratcheting up all the wrong ingredients ECM is not quite as bad, and shows a less stormy swathe of precipitation, although still heavy in western areas.

http://en.vedur.is/photos/atlant_evr_urkomuspa/120812_0000_90.png

UKMO still shows what would be the most preferable scenario of all and makes much less of the low

Either side of that it looks like some sunshine, some showers - the showers mostly in the north and west other than some rain generally tomorrow

The Met/o fax for Wednesday looks pretty nasty for the time of year;

http://www.wetterzentrale.de/pics/brack2a.gif

After that clears though its warm and changeable thereafter.

Originally Posted by: Gavin P

Here's todays video: Soaking Rain On Wednesday: http://www.gavsweathervids.com/

Quite an unusual event this (if it comes off as progeed) with 15c+ 850's fueling an intense area of low pressure just to the south-west approaches.

What are we looking at here - a severe and intense downpour. How much rain 50mm to 75mm??

Well at least the weather did the decent thing and gave the Olympics some breating space in the tune of some relatively OK weather.

So its back to the crap summer next week so it seems.

Well. Lets not let it upset us.

Anyay before I go OT any more.

The models on GFS.

Doesn't all look bad - some is - but not all of it - Out to 28th.

http://www.jp2webdesign.co.uk/ds/gfs.htm

Originally Posted by: Steam Fog

Originally Posted by: Hungry Tiger

Well at least the weather did the decent thing and gave the Olympics some breating space in the tune of some relatively OK weather.

So its back to the crap summer next week so it seems.

Well. Lets not let it upset us.

Anyay before I go OT any more.

The models on GFS.

Doesn't all look bad - some is - but not all of it - Out to 28th.

http://www.jp2webdesign.co.uk/ds/gfs.htm

 

First half of summer was certainly very poor. Second may end up being quite a bit better. Not the whole way through obviously and rather depends which way the FI see saw goes. But the last week of July, second week of August have been pretty pleasant.

IMBY taking all things into account its probably the best 3 week spell of summer weather since 2006 (the week of low pressure last week only delivered a few showers in total here). Late June/early July 2010 is also a contender but i recall it being rather cloudy at times.

The models show a change to a more changeable regime through the coming weeks with the emphasis switching to spells of rain or showers punctuated by drier and more settled periods. With southwesterlies prevailing it should be consistently warm by day and by night. Still very acceptable conditions for Summer and a far cry from the dreadful pattern of June.

Just a sign that winds may tilt more westerly to end the month so temperatures dropping back. But thats a long way off.

Edited by user 12 August 2012 12:54:49(UTC)  | Reason: Not specified

Originally Posted by: Gavin P

Originally Posted by: Hungry Tiger

Originally Posted by: Gavin P

Here's todays video: Soaking Rain On Wednesday: http://www.gavsweathervids.com/

Quite an unusual event this (if it comes off as progeed) with 15c+ 850's fueling an intense area of low pressure just to the south-west approaches.

What are we looking at here - a severe and intense downpour. How much rain 50mm to 75mm??

 

Difficult to say, but in the video I say theres the possibility of 50mm in places. I suppose it will depend whether we get embedded thunderstorms or whether its just a general thundery/torrential rain. Certainly looks quite unusual.

Does look unusual to see temps as high as these near such a depression

http://www.wetterzentrale.de/pics/Rtavn7817.png

http://www.wetterzentrale.de/pics/Rtavn782.png

Appears almost tropical

http://www.wetterzentrale.de/pics/Rtavn784.png

met office forecast for my area weds / thurs does not look that bad, so we will have to wait and see.