Astronomy, Photography and Weather
March 29, 2024, 08:01:43 am
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  

Thunderstorm Outlook - Wed Sept 3rd

Pages: [1]
  Print  
Author Topic: Thunderstorm Outlook - Wed Sept 3rd  (Read 451 times)
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« on: September 03, 2008, 10:58:16 am »



Synopsis Situation
A low pressure system over Northern Ireland during the morning will move across the north of the UK. An occlusion associated with the low will sweep across the north of the UK affecting parts of Wales, the northern midlands, and Northern England. In the far north of Scotland a further occlusion drifts into the far north of Scotland.

Northern Scotland
Some heavy showers and an isolated storm seem possible in association with an occlusion moving in. Instability is unlikely to be particularly high and the wind environment is not particularly indicative of severe thunderstorms. Light winds do indicate a possibility of weak funnels created from vertical vorticity sources especially along any convergence zone.

Northern Ireland
Once the occlusion moves away then Northern Ireland should see plenty of showers due to peak daytime heating and steep mid level laspe rates. Models are reluctant to break out much in the way of precipitation, despite having the highest forecast instability for the UK. Taking into account the wind field is fairly weak the risk of severe weather is not thought to be high enough for a slight risk to be issued.

North Wales, North West England, Western Scotland (See Text Area)
An occlusion swings across this region during peak heating hours with models suggesting some moderate rainfall from this in the period after lunch to mid afternoon. Instability from this looks quite low and forecast atmospheric profiles look moist all the way up, so although there may be a few embedded thunderstorms it seems unlikely that these will be severe. Attention is drawn to the fact that wind profiles are conducive to mesocyclone formation with an associated tornado risk; however updraft strengths may not be high enough for this to become a factor. Attention is also drawn to the Edinburgh Glasgow corridor where a low level convergence zone is forecast from mid afternoon onwards giving a slightly higher tornado risk. Instability does increase after the occlusion but wind fields by then are more benign. Taking all factors into account instability is not high enough under the occlusion to warrant issuing a severe thunderstorm risk, but this area should be monitored through the day for developments.


Issued by: Brickfielder - Forecaster for Netweather
Report Spam   Logged

Share on Facebook Share on Twitter

brianb
Hero Member
*****
Posts: 1228



View Profile
« Reply #1 on: September 04, 2008, 10:59:32 am »

Nothing for today Sep 4th?

I don't know where the energy is coming from but there appears to be fairly strong convection up here already. Not fierce electrical storms but I think there's at least some possibility they might develop. Surprised since there was no evidence of anything other than bits of cirrus & drifting patches of stratocumulus from midnight through to 5am ...
Report Spam   Logged
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #2 on: September 04, 2008, 01:06:49 pm »

Hi Brian,

The forecasters are giving nothing for Ireland today, the risk of storms is for mainland Britain. Still can't rule out some nice convection here due to ground heating or isolated showers. Did you hear anything about a waterspout being seen a few days ago from the north coast?

Here's the outlook for today....

http://www.estofex.org/

Low pressure system will hit Ireland over next few days from the SW. Looks like serious rainfall for some, and maybe some storms.
« Last Edit: September 04, 2008, 01:09:46 pm by martinastro » Report Spam   Logged

brianb
Hero Member
*****
Posts: 1228



View Profile
« Reply #3 on: September 04, 2008, 01:48:22 pm »

Quote
The forecasters are giving nothing for Ireland today, the risk of storms is for mainland Britain. Still can't rule out some nice convection here due to ground heating or isolated showers. Did you hear anything about a waterspout being seen a few days ago from the north coast?
I think it was a trough going through, the convestion is still visible to the ENE


No, I didn't hear about the waterspout.
Report Spam   Logged
martinastro
Martin Mc Kenna
Global Moderator
Hero Member
*****
Posts: 5182


Maghera, N. Ireland


View Profile WWW
« Reply #4 on: September 04, 2008, 02:22:28 pm »

I see what you mean Brian, good line of convection there.
Report Spam   Logged



Pages: [1]
  Print  
 
Jump to:  

Bookmark this site! | Upgrade This Forum
SMF For Free - Create your own Forum

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