Thunderstorm/Convective Watch: Summer 2010

maquiladora

Looks like a bit of an upgrade on the 12Z GFS from the last run for Wednesday.

Deep Easterly

Fax chart has the front wavering over Leinster on Wednesday afternoon: (size reduced as those charts are huge!)



Could be a wet day in places.

Gerry howley

very interesting movements we cud do with a thunderstorm a bit of drama .fingers crossed:)

Deep Easterly

Gerry howley wrote: »

very interesting movements we cud do with a thunderstorm a bit of drama .fingers crossed:)

The set up is certainly interesting in itself. Moist tropical maritime airmass clashing directly with dry polar airmass:



which the frontal zone posted above is more or less where these two airmass meet. It would be heart-breaking if this type of set up did not bring a few flashes and bangs at least some parts of Ireland as it passes through, whether they be contained within the actual front or in the showers that develop in its wake during Wednesday afternoon.

Although I already know that any thunder will avoid my patch as usual

IMC042

If only forecasts were right it would definately be an exciting day!!

I know this map is not very credible though.

TORNADO = ORANGE / SPOUT = GREEN INDEX - WED 22 SEP, 12.00PM

maquiladora

IMC042 wrote: »

If only forecasts were right it would definately be an exciting day!!

I know this map is not very credible though.

TORNADO = ORANGE / SPOUT = GREEN INDEX - WED 22 SEP, 12.00PM

Lumi

Deep Easterly wrote: »

.

Although I already know that any thunder will avoid my patch as usual

Seeing as the reverse psychology technique has had a zero sucess rate this summer, how about trying a different tactic for a change.


Focus on the picture and think positive thundery thoughts for Tuam

IMC042

Just seen the weather on RTE. They seem to think its just a band of showers, possibly heavy, that will quickly pass over during tuesday night / wednesday.

Not a word about thunder. But then, when have they ever been right?

Su Campu

Ya know, the setup Wednesday is looking awfully similar - if not identical - to 25th/26th July 1985!

maquiladora

Well if that doesnt jinx it into oblivion, nothing will.

Deep Easterly

Fionagus wrote: »

Seeing as the reverse psychology technique has had a zero sucess rate this summer, how about trying a different tactic for a change.


Focus on the picture and think positive thundery thoughts for Tuam

Thanks F, won't hurt to give it a go I suppose...:pac:

18z GFS CAPE chart for Wednesday afternoon:



Still showing the slight upgrade from the 06z run as Maq pointed out earlier.

IMC042

Since we are being positive now, I expect a tornado similar to this to form near my house and pass straight by me some time on wednesday / thursday!!! FACT

maquiladora

Looks like a minor downgrade again on the 0Z run in terms of the spread of good amounts of CAPE. Will have to wait for the 06Z to see if this is a trend.

Also, Met Eireann still not mentioning any thundery potential at all for Wednesday...

Wednesday morning will be wet over much of Leinster and east Ulster with further rain. Brighter weather with occasional heavy showers will gradually extend from the west to all areas through the morning and early afternoon. Highest temperatures of 16 to 19 degrees with light to moderate southwest breezes.

maquiladora

Well the 06Z GFS has swung back the other way and is showing better CAPE/LI figures, over a wider area and for longer. :pac:

Iancar29

HERES TO WEDNESDAY ! :rolleyes::rolleyes::rolleyes:

maquiladora

Most of the island of Ireland inside the blue "significant tornado" area tomorrow afternoon. :pac:

Not sure how reliable those kind of charts are but there could be be a few funnels at least.

maquiladora

12Z GFS looks like another slight upgrade again from the 06Z for tomorrow afternoon.



Met Eireann forecast hasn't updated on their website since 05:08AM. So still no mention of thunder there...

IvySlayer

Hope this stays true

Su Campu

maquiladora wrote: »

Most of the island of Ireland inside the blue "significant tornado" area tomorrow afternoon. :pac:

Not sure how reliable those kind of charts are but there could be be a few funnels at least.

Here's a guide to using the Lightning Wizard charts.

The tornado parameter is only an experimental index and shouldn't be taken too literally on its own.

Significant Tornado Parameter is a composite index based on deep layer and low level
shear, CAPE, CIN and LCL height. It highlights regions where these ingredients for
tornadoes come together most, although it does not tell which necessary ingredient may
be lacking most. Composite indices cannot replace a detailed analysis, but serve well as
an alert to the forecaster.

I reckon the heaviest of the showers will be in the east and north at first, but with the trailing occlusion edging southwards, it sould give the trigger for some more organised thundery rain in the northwest and west.

IMC042

RTE have updated their forecast and have included the potential for thundery showers tomorrow.

WEDNESDAY 22 SEP

A generally cloudy start to Wednesday, with further rain, persistent and heavy in parts of the east and southeast. Brighter showery weather in the west will spread to all areas by the afternoon, but some of the showers will be heavy and possibly thundery. It will remain mild and humid, with temperatures reaching between 17 and 19 degrees

maquiladora

Su Campu wrote: »

Here's a guide to using the Lightning Wizard charts.

The tornado parameter is only an experimental index and shouldn't be taken too literally on its own.



I reckon the heaviest of the showers will be in the east and north at first, but with the trailing occlusion edging southwards, it sould give the trigger for some more organised thundery rain in the northwest and west.

Take a look at the same chart but with the latest output

http://lightningwizard.estofex.org/Europe/gfs_stp_eur27.png

Notice within the blue area this time there is a small yellow area in the east, looks like a slight upgrade for tornado potential just west of Dublin. :P

Su Campu

ESTOFEX have highlighted the whole of Ireland with a chance of thunderstorms tomorrow.

Storm Forecast
Valid: Wed 22 Sep 2010 06:00 to Thu 23 Sep 2010 06:00 UTC
Issued: Tue 21 Sep 2010 21:57
Forecaster: PUCIK


SYNOPSIS

At midlevels, a ridge of high geopotentials will stretch from the Southwestern Mediterranean into Central Europe and Southern Sweden. This feature will have a slow eastward movement, especially at its northern fringe. To the west and east of the ridge, troughs are simulated by models. A shallow cold core low will move over Southern Italy during the day and this feature will significantly contribute to the destabilisation over this region. At upper levels, a polar jet-stream will be curved around the synoptic features desribed above. To the south, an anticyclonically curved subtropical jet-stream will stretch across the Southwestern Mediterranean (Iberian penninsula).

Several regions might experience thunderstorm activity but it does not seem that any will include an organised severe thunderstorm risk as no sufficient overlap of instability, wind-shear and forcing is forecast. It might be worth mentioning that Central Tunisia and eastern coastal seas of Tunisia might see some severe thunderstorms during the late afternoon and evening hours, but this regions is obviously out of the scope of the forecast map.

Su Campu

maquiladora wrote: »

Take a look at the same chart but with the latest output

http://lightningwizard.estofex.org/Europe/gfs_stp_eur27.png

Notice within the blue area this time there is a small yellow area in the east, looks like a slight upgrade for tornado potential just west of Dublin. :P

You mean around the Celbridge area??!!

IMC042

Absolutely pelting it down here now in cork! very windy too! i'm waiting for the fireworks

ninebeanrows

Some chunky stuff into the southwest already tonight.


(Copyright Met Eireann)

maquiladora

http://andvari.vedur.is/athuganir/eldingar/

A few strikes off the west coast already.

Su Campu

Latest aviation forecasts have slight chance of moderate thunderstorms for Donegal and Sligo airports, and heavy thunderstorms at Derry and the two Belfast Airports. Moderate rain showers for the others.

snowjon

Su Campu wrote: »

Latest aviation forecasts have slight chance of moderate thunderstorms for Donegal and Sligo airports, and heavy thunderstorms at Derry and the two Belfast Airports. Moderate rain showers for the others.

ooo - excellent! I hope we see a thunderstorm - I've only seen one weak thunderstorm here this year!

maquiladora

http://www.meteoalarm.eu/index2.php?country=IE&day=0&lang=

Su Campu

snowjon wrote: »

ooo - excellent! I hope we see a thunderstorm - I've only seen one weak thunderstorm here this year!

They put it down as a 30% probability, so don't get too excited just yet!! :P