Thunder Potential - UK & Ireland - Thurs-Sun

[martinastro]

Just a quick heads up - GFS showing good CAPE in conjunction with warm to hot temps and humidity which could trigger a few convective showers and isolated thunderstorms over N. Ireland, Ireland and Britain from Thurs to Sun. Thunder was reported yesterday evening from elevated convection over Magherafelt.

[martinastro]

Storm Forecast Issued: 2010-05-20 21:36:00
Valid: 2010-05-21 00:00:00 - 2010-05-21 23:59:00

Regions Affected
E/NE Scotland (Wales, N England, S Scotland & Northern Ireland included in the WATCH)

Synopsis

A broad area of HIGH pressure, "Siegbert", situated across the United Kingdom will dominate the weather on Friday.

Local convergence zones are forecast to develop across some parts of Scotland, N England, Wales and Northern Ireland during the day in response to daytime heating. This will provide focus for scattered, fairly isolated, sharp showers with a low risk of a localised thunderstorms.

Any showers will be very slow moving and this, combined with torrential downpours, increases the risk of flash flooding. Showers will gradually ease in intensity and coverage during the evening hours after sunset.

[Padraig OBrien]

Had a hot and sultry day here Max temp 24c. Feels thundery now with thunderstorms now being reported West of here!

[martinastro]

Seen those t-storms on the radar Padraig - looked great. That's a good radar return from those showers moving N at the moment.

Conor seen a huge cell with anvil before sunset this evening in the NE with solid dark towers at the back of it.

[R Newman]

What Radar do you use martin, I am looking at the Met Eireann site, had a really heavy shower 2 hrs ago here in Galway, some lightning, seems to have formed into a small supercell. Heading your way!


Ronan Newman

[martinastro]

Hi Ronan

I use the Met Office radar...

http://www.metoffice.gov.uk/weather/uk/radar/

Those showers have moved over the far W of NI now - no more sferics on the charts at this time but they still do look intense. That sounds like a great cell you had!

[martinastro]

Outlook for Sat...



Storm Forecast Issued: 2010-05-21 23:37:00
Valid: 2010-05-22 00:00:00 - 2010-05-22 23:59:00

Regions Affected
Northern Ireland (C + E Scotland and N England included in the WATCH)

Synopsis

A broad area of HIGH pressure, "Siegbert", continues to sit across the United Kingdom, dominating the weather on Saturday.

Local convergence zones are forecast to develop across some parts of Scotland, N England and Northern Ireland during the day in response to daytime heating. This will provide focus for scattered, fairly isolated, sharp showers with a low risk of a localised thunderstorms.

Any showers will be very slow moving and this, combined with torrential downpours, increases the risk of flash flooding. Showers will gradually ease in intensity and coverage during the evening hours after sunset.

However, current guidance suggests showers are likely to develop across Northern Ireland in the evening hours, drifting slowly northeastwards with a moderate (>40%) risk of electrical activity, hence the need for a Thunderstorm Threat Level here.

[martinastro]

For Sun...



Storm Forecast Issued: 2010-05-22 21:28:00
Valid: 2010-05-23 00:00:00 - 2010-05-23 23:59:00

Regions Affected
SE Scotland, NE England, Yorkshire & E Midlands (C, E + S Scotland, NW England, NE Wales, N Midlands and N East Anglia included in the WATCH)

Synopsis

A broad area of HIGH pressure, "Siegbert", continues to sit across the United Kingdom, dominating the weather on Sunday.

Local convergence zones are forecast to develop across some parts of E + SE Scotland and NE England during the day in response to daytime heating and falling heights. This will provide focus for scattered, fairly isolated, sharp showers with a low risk of a localised thunderstorms.

Any showers will be very slow moving and this, combined with torrential downpours, increases the risk of flash flooding. Showers will move slowly southeastwards, gradually easing in intensity and coverage later in the evening after sunset. There is a chance for the development of a convergence-type funnel.