Astronomy, Photography and Weather
August 24, 2019, 09:10:51 pm
Welcome, Guest. Please login or register.

Login with username, password and session length
News: IAA lecture programme continues alternate Wednesdays from September - an excellent programme of lectures- Queens University Belfast - Bell Lecture Theatre. Also keep an eye out for the Summer Events
 
  Home Help Search Gallery Staff List Login Register  

Possible Stormy Spell 13th to 19th Nov

Pages: 1 [2] 3 4 ... 6
  Print  
Author Topic: Possible Stormy Spell 13th to 19th Nov  (Read 3271 times)
Padraig OBrien
Full Member
***
Posts: 192



View Profile
« Reply #15 on: November 12, 2009, 10:07:30 pm »

Wow thats some read!!!!! Shocked
Report Spam   Logged

LG Renoir KC910 8 Mp Camera Phone
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #16 on: November 12, 2009, 10:41:00 pm »

Bad flash floods in Cork yesterday...



Credit: Irish Weather Network.
Report Spam   Logged

martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #17 on: November 13, 2009, 02:55:32 pm »



TORRO TORNADO WATCH 2009/009

A TORNADO WATCH has been issued at 13:20GMT on Friday 13th November 2009

Valid from/until: 13:20 - 14:00GMT on Friday 13th/Saturday 14th November 2009, for the following regions of the United Kingdom & Eire:

Parts of (see map)

All of England and Wales

S Scotland

Eire
N Ireland

THREATS

Tornadoes; wind gusts to 80mph; hail to 15mm diameter; CG lightning

SYNOPSIS

Rapidly deepening low exhibiting warm-seclusion characteristics will push an active set of fronts across the British Isles today and tonight, and then an active occlusion/trough eastwards across southern parts tomorrow.

Convection is currently occurring in the strong warm advection regime near SW England, and will spread northwards this afternoon and evening across western parts. This brings the risk of strong winds and hail, and CG lightning, but also a slight risk of tornadoes - the risk extending along the south coast and perhaps into other areas of S England this afternoon along the northward moving front.

Overnight tonight a strong cold front will surge eastwards bringing squally wind gusts of up to 65mph inland and 70mph on the south coast, some aided by convection. In addition, a chance exists for a few tornadoes, perhaps strong. This risk is mainly for central and southern England and Wales.

Later tonight and through tomorrow morning, an active occlusion will be pushed eastwards across England and Wales, again especially across southern parts. Some severe convection may accompany this, bringing wind gusts of up to 80mph in exposed SW'ern parts, and 60-70mph elsewhere. A risk of tornadoes exists with this too, especially if convective lines develop.

The purple area on the WATCH map is the region deemed most at risk from severe winds - a dangerous situation as inland gusts this high are rare in southern Britain.

Forecaster: RPK
Report Spam   Logged

Padraig OBrien
Full Member
***
Posts: 192



View Profile
« Reply #18 on: November 13, 2009, 04:55:12 pm »

Quite a set up so and so

Very nasty looking skies here atm very dark
Report Spam   Logged

LG Renoir KC910 8 Mp Camera Phone
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #19 on: November 13, 2009, 05:11:11 pm »

ESTOFEX have a level 2 out for S. UK!!!, first time I've ever seen this. Level 1 area also extended across much of Ireland and UK.



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 -30C 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.

... Extreme NW-Spain and extreme N-Portugal ...

Difficult to determine the environment, where current thunderstorm activity is embedded. At the tip of the WCB, a warm and moist inflow beneath eastward spreading cooler mid-level air supports numerous thunderstorms, and conditions remain supportive at least until "landfall" of this warm conveyor belt. In fact, up to 500 J/kg MLCAPE, roughly 100 J/kg 0-3km CAPE, LCLs below 500m, 20m/s 0-1km speed shear and 200-300 m^2/s^2 SRH1 are supportive for tornadic supercells (a strong event possible), next to damaging wind gusts, given 35m/s at 850hPa. Therefore, a level 2 was included. The severe risk will be maximized probably between 17-21 UTC, decreasing rapidly over the Bay due to the clipping of the inflow by the Iberian Peninsula. The risk also decreases to the south along the west coast of Portugal, as shear gradually relaxes.

« Last Edit: November 13, 2009, 05:20:27 pm by martinastro » Report Spam   Logged

Roman White
Hero Member
*****
Posts: 1479


Poltava, Ukraine


View Profile WWW
« Reply #20 on: November 13, 2009, 05:36:22 pm »

ESTOFEX have a level 2 out for S. UK!!!, first time I've ever seen this. Level 1 area also extended across much of Ireland and UK.
Mmm... looking forward for any reports  Roll Eyes
Report Spam   Logged

SkyWatcher 130/900mm EQ3, Bresser 76/700mm, 20x90 bino. and other, Olympus SP-550UZ
Eclipse & comet chaser, occultation & meteor observer
Poltava Astronomy Portal
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #21 on: November 13, 2009, 05:44:57 pm »

This is fast becoming the most interesting severe weather forecast and event of the year for the UK. The net is buzzing with storm chat. There's a real possibility of a tornado outbreak from this storm. Severe weather warnings appearing everywhere, even for NI for flooding. 74mph gusts already reported at Land's End with thunderstorms moving into the SW coast of Britain. This is from the UKASF...

A very deep area of LOW pressure to the Southwest of the United Kingdom will bring severe weather to parts of the country over the next 24-36 hours. Heavy, slow moving rain, with an increased risk of embedded thunderstorms, will affect parts of England and Wales through the rest of today and tonight. Torrential, persistent rain may lead to local flooding in places. Conditions will be quite favourable for the development of tornadoes, which if they do occur could be moderate in intensity and cause structural damage. Very strong winds will affect southern England and south/west Wales this evening and tonight, with gusts up to 80mph possible in exposed locations. Winds may be strong enough to cause structural, power and transport disruption.
Report Spam   Logged

markt
Hero Member
*****
Posts: 1416

West Midlands, UK


View Profile
« Reply #22 on: November 13, 2009, 05:55:18 pm »

Tis' pretty wet here in the west mids at the moment, winds not kicked in yet, though i'm sure they will...
Report Spam   Logged

Padraig OBrien
Full Member
***
Posts: 192



View Profile
« Reply #23 on: November 13, 2009, 07:07:20 pm »

Heavy rain here now winds have really kicked off now
Report Spam   Logged

LG Renoir KC910 8 Mp Camera Phone
paulster78
Hero Member
*****
Posts: 752


Omagh, N. Ireland


View Profile WWW
« Reply #24 on: November 13, 2009, 08:55:33 pm »

Yeah Padraig the Republic is getting some very heavy rainfall right now. Dry here with only a slight breeze.
Report Spam   Logged

martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #25 on: November 13, 2009, 08:56:41 pm »

Reports of flooding and damage in the S of Britain with lightning/possible power flashes and trees brought down through a house, and another incident on a car, the occupants of which were cut free by the firebrigade. Strongest radar echoes at the moment are over Ireland.
Report Spam   Logged

Padraig OBrien
Full Member
***
Posts: 192



View Profile
« Reply #26 on: November 13, 2009, 10:46:27 pm »

Quite a show over there just had a very squally heavtyish shower if i can put it that way quite strong winds the rain band is well gone now from here Huh?? i though different
Report Spam   Logged

LG Renoir KC910 8 Mp Camera Phone
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #27 on: November 13, 2009, 10:48:21 pm »

The ROI have been getting intense radar echoes now for some time, there's a nasty large persistant white return in SW Ireland (inland) which appears to be rotating when I flick through the Met O radar during the recent updates. I wonder if it's a convective cell rotating?
Report Spam   Logged

Padraig OBrien
Full Member
***
Posts: 192



View Profile
« Reply #28 on: November 13, 2009, 10:53:35 pm »

What  I don't understand is that even when the heaviest rain is forecast for the east of the country the west always gets it worse?Huh?
Report Spam   Logged

LG Renoir KC910 8 Mp Camera Phone
brianb
Hero Member
*****
Posts: 1228



View Profile
« Reply #29 on: November 13, 2009, 11:02:02 pm »

Quote
when the heaviest rain is forecast for the east of the country the west always gets it worse?
Easteners and southerners are soft. The South East of England is making a big fuss over the sort of storm I'd expect to see here three or four times every winter.
Report Spam   Logged


Pages: 1 [2] 3 4 ... 6
  Print  
 
Jump to:  

Bookmark this site! | Upgrade This Forum
SMF For Free - Create your own Forum | Buy traffic for your forum/website

Powered by SMF | SMF © 2016, Simple Machines
Privacy Policy