Convective/storm Discussion Thurs 23>>>>>>>>>

[maidstone weather]

ESTOFEX ain't having it tomorrow Paul S/Nick :ph34r:

[Wilxy]

Rain has got heavy now.

Wow so unexpected v heavy rain or downpour here currently.

[Noctilucid]

Interesting, lets see if Romford can make it at least one day of thunder heard every week for 6 weeks in a row. :ph34r:

Edited July 28, 2009 by jshaw

[sunny scunny]

Very dark here and it's just started chucking it down :ph34r:

[Costa Del Fal]

Just had a torrential downpour here-pretty much the only one in this band of rain!!!

This does not bode well for tomorrow-very concerned for parts of SW England, Gloucestershire, West Midlands, Worcestershire and Herefordshire.

[Wilxy]

Just had a torrential downpour here-pretty much the only one in this band of rain!!!

This does not bode well for tomorrow-very concerned for parts of SW England, Gloucestershire, West Midlands, Worcestershire and Herefordshire.

Looking better here for downpours now on latest bbc forecasts.

[Costa Del Fal]

Looking better here for downpours now on latest bbc forecasts.

Although they can be fun we dont really want them here this time. The July 2007 flood in our areas was terrible. The West Midlands, Worcestershire and Gloucestershire was hit so bad.

[SteveB]

Although they can be fun we dont really want them here this time. The July 2007 flood in our areas was terrible. The West Midlands, Worcestershire and Gloucestershire was hit so bad.

It looks very wet indeed tomorrow. Thats if the path shown is were it ends up.

[Andy Bown]

The BBC Points West forecast showed very heavy rain over Wiltshire/Somerset/Dorset/South Gloucestershire mid-afternoon tomorrow and the forecaster spoke of the cold front bringing the risk of hail, thunder and strong gusts of wind.

I think it's important to not look at the radar mid-morning and let hopes be dashed, because the rain will be moderate in this area until the heavier rain develops into the afternoon.

[Wilxy]

The BBC Points West forecast showed very heavy rain over Wiltshire/Somerset/Dorset/South Gloucestershire mid-afternoon tomorrow and the forecaster spoke of the cold front bringing the risk of hail, thunder and strong gusts of wind.

I think it's important to not look at the radar mid-morning and let hopes be dashed, because the rain will be moderate in this area until the heavier rain develops into the afternoon.

Latest bbc graphics on the national forecast looks even better now so tomorow will be so intresting.

[dave48]

The BBC Points West forecast showed very heavy rain over Wiltshire/Somerset/Dorset/South Gloucestershire mid-afternoon tomorrow and the forecaster spoke of the cold front bringing the risk of hail, thunder and strong gusts of wind.

I think it's important to not look at the radar mid-morning and let hopes be dashed, because the rain will be moderate in this area until the heavier rain develops into the afternoon.

Good shout. Looking forward to tomorrow.

[Paul Sherman]

ESTOFEX ain't having it tomorrow Paul S/Nick

http://www.ukweatherworld.co.uk/forum/forums/thread-view.asp?tid=31759&posts=4

Maybe Estofex are gonna have to play Catch-Up MW!

Still looking like game on to me and a lot of others over on Ukww - See Above!

Paul S

[maidstone weather]

http://www.ukweather...d=31759&posts=4

Maybe Estofex are gonna have to play Catch-Up MW!

Still looking like game on to me and a lot of others over on Ukww - See Above!

Paul S

I like the sound of that Fingers crossed!

Cheers Paul

[Cookie]

very heavy rain here and a couple of rumbles of thunder.

got this from the local weather station

===== TSentry™ THUNDERSTORM ALERT NOTIFICATION ======

issued by Hebrides Weather (www.hebwx.co.uk)

-----------------------------------------------------

Alert message issued at Tue Jul 28 20:21:08 2009

-----------------------------------------------------

Warning: Thunderstorm detected within 250 mi range!

Active warnings:

- CLOSE STORM WARNING

Close alarm range: 250 mi

Expanded info:

TRAC ID W-2694

BEARING 323.5 dgr

RANGE 77 mi

STRIKE RATE 3/min

PEAK RATE 4/min

CATEGORY WEAK

TREND NO CHANGE

Short info:

ID:W-2694 BNG:324 RNG:77mi CAT:WK SR:3 PR:4 TR:NC

Trigger configuration:

Close alarm mode: TSentry

Close alarm range: 250 mi

Severe storm alarm: Enabled

Severe stormcell alarm: Enabled

then just under 1 hr ago

===== TSentry™ ALL CLEAR NOTIFICATION ===============

issued by Hebrides Weather (www.hebwx.co.uk)

-----------------------------------------------------

Notification issued on Tue Jul 28 21:08:52 2009

------------------------------------------------------

No lightning activity detected in 20 minutes

Total time under alert: 0 h 47 m

[dogs32]

Estofex has a warning out for the West

and Amber warning's from the Met

Edited July 29, 2009 by dogs32

[SteveB]

Looks like a day of heavy rain, with again the exact track still not clear.

[Coast]

Maybe Estofex are gonna have to play Catch-Up MW!

I think they just have:

Storm Forecast

Valid: Wed 29 Jul 2009 06:00 to Thu 30 Jul 2009 06:00 UTC

Issued: Tue 28 Jul 2009 16:22

Forecaster: TUSCHY

A level 1 was issued for NW-Germany, E-Netherlands and E-Belgium mainly for severe wind gusts.

SYNOPSIS

The progressive weather pattern continues over parts of west/northwest Europe. A strong upper trough crosses UK during the day and enters the North Sea during the evening hours. A surface depression and the attendant cold front serve as foci for unsettled and windy conditions. Hot and stable conditions persist over the Mediterranean with warm and unstable conditions over eastern Europe beneath a weak upper trough.

DISCUSSION

...E/NE-France, Luxembourg, Belgium, the Netherlands and NW/N-Germany, 18 UTC onwards ...

Global models agree in a rapidly eastward translating upper trough, which crosses the area of interest during the night hours from the SW. Placed under the left exit region of a vigorous mid-/upper jet, a deepening surface depression over the southern North Sea will push an active cold front to the eastnortheast, crossing Belgium and Luxembourg between 18 - 00 UTC and NW-Germany until 06 UTC. The position of the depression is well captured in the NCEP-ensemble with slight oscillations regarding the strength still present. Rest of the models are in line with only marginal discrepancies regarding timing of the cold front passage.

Main issue is the strength and quality of the return flow ahead of the cold front. GFS forecasts an increase of surface dewpoints of roughly 10°C in 24h which seems too aggressive given current dewpoint reports further upstream. However, a tightening gradient ahead of the line ought to increase advection to the north, so coupled to ongoing evapotranspiration and moisture pooling along the front itself, at least mid-tens will be reasonable to forecast over NW-Germany, Luxembourg and E-France. Mid-level lapse rates steepen somewhat during the forecast and a small prefrontal tongue of 100-500 J/kg MLCAPE will likely persist during the night ahead of the cold front.

Marginal thermodynamics may be offset by very strong dynamics, as the trough draws near during the night. In addition, an unseasonable strong IPV anomaly accompanies the trough and there are indications that an active dry slot crosses the area of interest during the night and overtakes the surface cold front. This effect could offset the generally expected minimum of convective activity after midnight with those marginal MLCAPE values. In addition to that, GFS also inclines the trough in a highly negative tilt, which causes the cold mid-levels to rapidly spread eastwards atop the still warm and moist surface layer and therefore increases MLCAPE release again after 03Z.

To harmonise all that, we expect the cold front to support isolated thunderstorm initiation over NE-France around sunset with increasing activity over E-Belgium, the eastern Netherlands and NW-Germany thereafter. A wavy, leading convection line is forecast along the cold front, given strong shear (25m/s at 0-6km, 20m/s at 0-3km) with a pronounced severe wind gust risk. This hazard could become more widespread over NW-Germany. An isolated tornado event can't be ruled out despite low SHR1 values but even a slight deviant storm motion could result in significantly better directional shear. The hail risk, although present, plays an subordinate role. The complete area was placed under a low probability thunderstorm area (not yet made public) with higher probabilities, where conditions look the best.

A strengthening jet below 700 hPa causes an enhanced severe wind gust risk over the Netherlands after 03 UTC. The thunderstorm risk looks too marginal right now to expand the level 1 more to the west.

E-France has to be monitored for initiation with better instability but marginal forcing.

And so have the UKASF:

Storm Forecast Issued: 2009-07-28 20:46:00

Valid: 2009-07-29 00:00:00 - 2009-07-29 23:59:00

Regions Affected

Western Scotland, Northern Ireland, east Ireland, Wales, Northwest England, Southwest England, Southeast England, East Anglia ( all parts of the UK are included in the WATCH )

Synopsis

A complicated setup across the UK on Wednesday. Cyclogenesis is forecast to occur as an area of LOW pressure develops and moves northeastwards over central UK to eastern Scotland by the end of the forecast period. A cold front, with numerous waves along it, will bring outbreaks of heavy across much of England and Wales. Although the front will effectively move eastwards during the course of the forecast period, more especially during the latter half of the period, the pulses of heavy and locally torrential rain will move northwards along the front itself, bringing an increased risk of flash flooding. There is a risk of embedded thunderstorms along the cold front, although the chance of these occurring seems somewhat less likely than thunderstorms behind the cold front. The cold front, and the associated heavy rain, should clear all parts of the UK (excluding E Scotland/NE England) by late evening. Across Ireland, Northern Ireland and Western Scotland, numerous showers and thunderstorms are forecast to develop in the airmass behind the cold front. The most favourable conditions will be across central/eastern Ireland - given the Polar Maritime airmass, hail can be expected to accompany many of the showers. These showers/storms are expected to move eastwards across the Irish Sea during the evening and may affect western parts of Britain during the remaining hours of the forecast period once the initial cold front clears these areas. Across Southeast England and East Anglia, but more particularly the Southern North Sea, embedded thunderstorms might develop either along the cold front, or along a trough behind the cold front, during the evening hours. Should any storms develop they would pose an enhanced tornado risk. However, this scenario is still uncertain, particularly as there is still some disagreement amongst the models. Southern North Sea and the Low Countries seems to exhibit more favourable conditions, but we will monitor the conditions on Wednesday and may issue an update if necessary.

Nothing yet from TORRO, a bit early in the morning for them!

Charts for today from other sources:

Looks like the main activity will be in Ireland and the West this morning, moving to the middle of the country (possibly top to bottom) but I can't yet see it affecting my little corner of the South East today, although we might see a fair bit of rain before the day is out.

Edited July 29, 2009 by Coast

[Tn9]

I think they just have:

And so have the UKASF:

Nothing yet from TORRO, a bit early in the morning for them!

Charts for today from other sources:

Looks like the main activity will be in Ireland and the West this morning, moving to the middle of the country (possibly top to bottom) but I can't yet see it affecting my little corner of the South East today, although we might see a fair bit of rain before the day is out.

So when we have applied sods law to all that info our chances are slimmer than normal,but a chance all the same,i will keep the eyes peeled then,you seem to have chucked the towel at the chickens before they have hatched,dont give up hope Coast,i look to you for inspiration every morning,and when you aint happy,then i is neither

[Coast]

you seem to have chucked the towel at the chickens before they have hatched,dont give up hope Coast

But we have ducks!

i look to you for inspiration every morning,and when you aint happy,then i is neither

Just can't get a positive hunch about the chances in our neck of the woods today (my enthusiasm hasn't wained though) as my very, very basic knowledge and round-up of all the clever people's information, gives me the feeling there isn't enough lift in that cold front when it gets to us.

I'll try and be inspirational on other occasions!

[Harry]

But we have ducks!

Just can't get a positive hunch about the chances in our neck of the woods today (my enthusiasm hasn't wained though) as my very, very basic knowledge and round-up of all the clever people's information, gives me the feeling there isn't enough lift in that cold front when it gets to us.

I'll try and be inspirational on other occasions!

If we get the sun out this afternoon (which looks possible) heating should give some additional lift and energy.....................hopefully

[dogs32]

Think tornadoes, of course, and you think the American Midwest. Yet I remember reading that the UK, for its land area, has more tornadoes than any other country in the world. So is the UK the real Tornado Alley?

While there are an estimated 50 tornadoes in Britain each year, very few are more than an F3 on the Fujita scale. In fact, the most intense recorded tornado in the UK occurred way back in 1091, demolishing churches and houses in London.

And a 2003 study suggests that per land area, the Netherlands in fact has more tornadoes than any other country, with the UK in second place.

I Havent seen one here Yet

Sorry went on a Tangent

going back today I think we are in for a nice deluge as the system down South moves up.

Cant see any sferic's though at present.

But over the last hr or so the rain as intensified in a few places..

Edited July 29, 2009 by dogs32

[Harry]

I've seen two definite funnels in the UK, which isn't bad

Sat24 showing some really quite 'lumpy bits' in that rain mass, indicating that in some areas it is intensifying quite nicely (or badly depending on how you're viewing it)

Window of clearer skies moving towards the SE from Northern France. How much the clearer skies spread in and precisely how the front aligns itself throughout the day will give us in the SE and better indication of whether convective stuff is reasonably possible or not.

GFS storm risk currently has areas of the SE at 40-50%...not too bad really.

[dogs32]

rain fairly heavy here at present.

See what you mean Harry does look like the depth of the clouds on radar seem to be increasing.

At present cant see much in the way of Thunder for today though.

But just heavy rain mainly

Edited July 29, 2009 by dogs32

[dogs32]

MET UPDATE,,09.51

North West England

Wales

Yorkshire & Humber

North East England

Heavy Rain Wed 29 Jul

There is a moderate risk of severe weather affecting much of Wales, Northern England and Southern Scotland during Wednesday. Rain will spread northeastwards during Wednesday, becoming heavy and persistent. Rain will slowly clear eastwards later in the day. Rainfall totals of 20 to 50mm are likely, with a small risk of 70-100mm locally.

Issued at: 0947 Wed 29 Jul

Surprised realy that there are no warning's here as it's been very heavy here for some time

Edited July 29, 2009 by dogs32

[sunny starry skies]

From BBC today: Funny how it's always a 'mini-tornado' or a 'funnel cloud' to the UK media - surely something like this that causes damage on the ground classifies as a fully-fledged (albeit small) tornado. Cookie, did you see this at all? Presumably from the storm warning you posted?!

sss

http://news.bbc.co.uk/1/hi/scotland/highlands_and_islands/8173784.stm

A number of cars and homes have been damaged by a mini tornado which hit the Isle of Lewis.

The twister, in Stornoway, flipped one car upside down, narrowly missing the fuel depot near the ferry terminal.

Slates, ridging and iron-work were also ripped off some houses following the weather phenomenon which happened just after 2200 BST on Tuesday.

Lightning also caused power to be lost across the town after residents reported hearing a 10-second blast.

Leicestershire couple Darren and Cathie Cassie and their two children had their camper van shaken so hard that one of the children was thrown out of a bunk and only a tractor parked next to the caravan stopped it overturning.

Mrs Cassie told BBC Scotland: "The van started to shake, almost like you were in an earthquake and then it tipped sideways.

"Fortunately we were parked right next to a tractor. It tipped into the tractor and then tipped back again..... [more in the link]