Friday 13th / Sat 14th Storms

[Marcus_surfer]

When are the real severe winds going to hit?

[Lewis]

When are the real severe winds going to hit?

for you, around about now - although later on they will get much stronger

*Reason for edit - Adding more information

Edited November 13, 2009 by Lewis

[Marcus_surfer]

for you, around 10-11pm

oh thanks, we have gusts of around 40-45mph at the moment, nothing out of the ordinary for this area.

[coldfingers]

My update warns of severe gust potential across southern England tonight and early Saturday.

I would not be surprised to see 90-100 mph gusts developing by midnight in the southwest and then these would spread especially near any convective cells on the fast-moving occlusion, which could develop into a squall line for southeast England 0300-0600h ... sound familiar? Not saying quite as bad as Oct 87 but the tight upper wind gradient and sharp wind shear developing are certainly conducive for tornadic cell development.

Anyone who loves stormy weather should be prepared to do an all-nighter on this one ... I will, but that's no big deal as my night begins at 4 p.m. :)

Thanks Roger, Let's hope it doesn't get as bad as '87 as that time my house was in a sheltered position. Now I have moved and am only half a mile from the beach so if it does get that bad I wouldn't have a choice about doing an all-nighter! METO forecast for possibly severe storm 11 for Wight so that will be bad enough thanks. Mind you I do love storms.

[dogs32]

Very gusty here now with heavy rain....

not sure Lynxus but i would think with another heavy pulse comming up from the south for later will cause some flooding

[chapmanslade]

There seems to be quite a lot of confusion on here tonight about what is or isn't happening, or going to happen - together with the usual over excited posts.

Here is my take on what is happening in simplified terms.

So far we are experiencing the warm front with significant rain for some and wind speeds that are enough to cause minor damage but nothing serious. This is transfering east across southern UK and is preceeded by a very mild calm area. The wind went from calm to 40mph gusts here in about 2 hours.

LATER in the early hours of Saturday after a relative lull an area of strong convection will move east across southern UK accompanied by the strongest winds. There is a very strong jet streak above with the potential for sting jet development towards the south coast. It is this area of convection that will be responsible for the most damaging winds and will probably last in the region of 3 hours in any one place. I suspect it will affect the far SW around 03Z and the SE around 10Z. There are several factors influencing the wind speed and so actual figures will be +/- 15% of predictions in my opinion and will vary over quite short distances.

For many it will be far from exciting seeing bits of their house fall off or wash away, and a storm of this intensity is rare for the south of the UK but relatively common for the north of Scotland. I for one will find the event interesting but will be more than happy to miss any 60mph plus gusts thank you very much.

[Marcus_surfer]

If we have 85mph winds here my neighbours shed will take off

[Evening thunder]

There's a serious blob of torrential rain in the channel moving straight for the east Devon, Dorset coast could be intreasting if it keeps its intensity when it hits land.

Yep keeping an eye on that, if it does maintain its intensity the stream across the road thats already high will likely flood onto the road and into the front garden. It will of course add to the water that is to make its way into the main river near here meaning its quite likely to flood too.

Pretty blowy here and sounding rather stormy out, however its not too extreme. Shame i can't position my anemometer slightly better for winds in the south.

[Lynxus]

Very gusty here now with heavy rain....

not sure Lynxus but i would think with another heavy pulse comming up from the south for later will cause some flooding

Looks like it could be quite bad.

Still no rain here though.

VERY blustery now.

[Devon-Nelly]

Yeah same here my annometer isnt in a good spot but i cant move it anywhere really, which is annoying as the highest its recorded today is 10.3mph when i know for a fact we've at least hit 40mph so far.

[Lewis]

Yeah same here my annometer isnt in a good spot but i cant move it anywhere really, which is annoying as the highest its recorded today is 10.3mph when i know for a fact we've at least hit 40mph so far.

I use to have that problem at my old house, but luckily i have a gap between houses in my back garden and the wind can whistle right through, so it's perfect for catching the wind speed

Dont go moving it now though, it's to dangerous to be climbing about.

[Dave Clarke]

A point to note, that the last strong storm in the south/south east was 18th Jan 07, and a lot of trees that would normally be felled by autumnal storms are still standing due to lack of anything for nearly 3 years. Tonight could see quite a few trees down in the south/south east.

[coldfingers]

METO Flash warnings out for the South

South West England: Cornwall & Isles of Scilly Devon Dorset Plymouth Somerset Torbay Severe Gales 1800 Fri 13 0100 Sat 14 An area of very strong winds will spread northwards across southwestern England during the evening. Gale force southerly winds are expected, becoming severe in places, with gusts as high as 65 to 75 mph. These winds are likely to cause damage to trees with possible disruption to travel.

The public are advised to take extra care and refer to the 'Highways Agency' for further advice on traffic disruption on motorways and trunk roads.

Issued at: 1543 Fri 13 Nov

London & South East England: Brighton + Hove Hampshire Isle of Wight Portsmouth Southampton W Berkshire W Sussex Severe Gales 1900 Fri 13 0200 Sat 14 An area of very strong winds will spread northwards across southern England and the West Midlands during the evening. Gale force southerly winds are expected, becoming severe in places, with gusts as high as 65 to 75 mph, especially in coastal areas. These winds are likely to cause damage to trees with possible disruption to travel.

The public are advised to take extra care and refer to the 'Highways Agency' for further advice on traffic disruption on motorways and trunk roads.

Issued at: 1628 Fri 13 Nov

Let's hope people have the sense to pay attention to the warnings rather than moan afterwards if they get injured. Hopefully everyone will stay safe.

Edited November 13, 2009 by coldfingers

[Zenarcher]

Ive uploaded the xcweather map and put on what current wind speeds are. Also the current NW radar. Around the South West England reporting wave height of 16ft.

[Snow Queen one]

I for one am not looking forward to this storm. Last time in 87 i was in an old victorian house which stood up well to the winds. The estate i now live in was hit pretty badly by the storm and the houses round here lost their roofs. I knew this before i moved here and thought it would be unlikely to happen again. I have had no trouble with my roof since and have had extensions pu ton the house so am hoping the work i have done is of a better standard to the builders who built this house in the first place.

Stay safe everybody and i hope it is not as bad as predicted.

It is a bit breezy outside at the moment dry the rain has stopped for now and very mild about 14 deg.

[Nick F]

18z WV imagery this evening shows a pronounced 'dry punch' on the rear-side of the cold front approaching from the SW, this dry air aloft will likely increase potential instability and may allow some of the stronger winds of the low-level jet aloft to sink to the surface as damaging wind gusts in any convective cells that form along the cold front moving NE:

Given backed winds ahead the cold front towards the surface from S/SE and strong SWerly winds aloft creating strong wind shear - certainly potential for tornado or two, even a strong one, given potential instability likely as dry air intrusion overlaps forced ascent of warm moist Tm air ahead of front + damaging convective gusts as the cold front passes through perhaps even a 'sting jet'.

[dogs32]

Looks like it could be quite bad.

Still no rain here though.

VERY blustery now.

are you serious Lynxus...we have had heavy rain now for a few hrs..

a feww nasty gusts here now.....

Edited November 13, 2009 by dogs32

[littlemissy]

According to Dunkeswell weather station we are having gusts around 54mph, and sustained winds 32mph.

Pressure 990hPa and falling.

[Wynn D Woo]

are you serious Lynxus...we have had heavy rain now for a few hrs..

a feww nasty gusts here now.....

We seem to have missed the worst of the rain, nearby stations are touting 4.8 - 5.0mm of rain for the day so far, which is less than i had hoped for, pity as Im more interested in rainfall than strong winds.

[Dave Clarke]

Sig tornado risk on Oscar's Lightning Wizard site for early hours of Sat am

[dogs32]

We seem to have missed the worst of the rain, nearby stations are touting 4.8 - 5.0mm of rain for the day so far, which is less than i had hoped for, pity as Im more interested in rainfall than strong winds.

have you got the Squally winds over there...

we have quite damaging gusts here.....you can here the wind high up howling...

my shed roof is bending with the gusts

showery in nature

Edited November 13, 2009 by dogs32

[West Sussex Kate]

Hold onto your hats!!

[Guest North Sea Snow Convection]

I for one am not looking forward to this storm. Last time in 87 i was in an old victorian house which stood up well to the winds. The estate i now live in was hit pretty badly by the storm and the houses round here lost their roofs. I knew this before i moved here and thought it would be unlikely to happen again. I have had no trouble with my roof since and have had extensions pu ton the house so am hoping the work i have done is of a better standard to the builders who built this house in the first place.

Stay safe everybody and i hope it is not as bad as predicted.

It is a bit breezy outside at the moment dry the rain has stopped for now and very mild about 14 deg.

I agree with you. I'm not looking forward to it either.

I am hoping that we might be that little bit further east from the worst of the weather. But that is not to wish it on anyone of course

[West Sussex Kate]

I agree i've only lived here for 6 months, i'd hate to have any damage to our new house!

[dogs32]

LEVEL 2

Forecast Update

Valid: Fri 13 Nov 2009 17:00 to Sat 14 Nov 2009 06:00 UTC

Issued: Fri 13 Nov 2009 16:55

Forecaster: TUSCHY

A level 2 was issued for the western English Channel and extreme SW-UK mainly for severe wind gusts and to a lesser extent for tornadoes.

A level 1 was issued for Ireland, Scotland and United Kingdom mainly for severe wind gusts and to a lesser extent for tornadoes.

SYNOPSIS

Please refer to the main outlook, issued at Thu 12 Nov 2009 21:22.

DISCUSSION

... Parts of the Bay of Biscay, the English Channel and UK ...

Latest remote-sensing data reveals an active warm conveyor belt (WCB), spreading NE-wards. Wave-like appearance in high resolution visible data and recently reported thunderstorms, embedded in this WAA regime, hint on CSI release, responsible for embedded line of enhanced convection (thunderstorms). Despite rapidly increasing wind fields, this activity of thunderstorms over SW/S-UK remains elevated in nature although not much BL modification is needed for near surface based activity. The main risk ought to be a severe wind gust risk although even an isolated tornado event can't be ruled out, given favorable backed wind profile and near zero CIN. Therefore, the low probability thunderstorm area was expanded significantly in all directions, to include active WCB, but also the anticipated more active backside of this belt due to the approaching cold front. Strong dry slot continues to punch northwards, a bit further west than what was expected yesterday. Enhanced convection is just about to reach Ireland, so the level 1 was expanded towards the west. Severe wind gusts and isolated tornadoes are possible over Ireland (most likely over SE/E-Ireland), W/central UK and most parts of Scotland. Degree of LL shear, increasing LL CAPE west of the WCB and low LCLs still indicates a chance for a strong tornado event, especially along the coast, where onshore swashing CAPE and shear overlap.

An upgrade was performed for the time-frame 00-06 UTC, although the severe risk continues later-on. Wrap-around moisture and already developing intrusion of dry high-level air just south of the warm core seclusion point to a developing sting jet event and cloud top loops show a warming trend along this spot. Despite a gradual decrease of deep convection in this area, a broad swath of deep convection is approaching SW-UK from the southwest. Forecast soundings and 06/12 UTC GFS runs still indicate an overlap of some CAPE (maximized over SW-UK, over the English Channel and over extreme NW-France). The overlap of 35-40m/s at 850hPa , approaching tongue of the wrap-around moisture and cool mid-levels indicate that not much is needed for damaging wind gusts producing deep convection and therefore a level 2 was issued to reflect the convective component in this concentrated severe wind event. A tornado event is possible along the SW/S-coast of UK and again, a strong tornado can't be excluded.

The most likely scenario will be an eastward racing forced line (EL temperatures below -30°C and beneath the left exit of a 65m/s mid-level streak) with the sting jet pointing into the backside of this line. After the passage of the line, thunderstorm chances most likely decrease over far SW-UK whereas damaging winds keep going. Thunderstorm chances will still be present further north along the W-coast of UK and Scotland also with severe wind gusts and an isolated tornado risk.

Edited November 13, 2009 by dogs32