Convective/Thunderstorm Discussion 2013/14

Would have loved to have seen that.

Thought id start a nice fresh one considering the week ahead

With the heat building in this week there also comes with , the risk of some "heat thunderstorms" . These are usually storms that kick off within high pressure zones but with some moisture to feed it. Storms that go up in high pressure areas generally do well for sferic activity but may not go severe with lack of shearing in general. I remember one such storm a few years back , i was watching a storm in the Mullingar area all the way from Trim, was a great evening sitting out in my friend's garden watching for distant strikes

We are looking at a possible 5 straight days of TS risks around most of the country. Inland areas will favour with the stronger surface heating.

Tomorrow , SUNDAY kicks the action ( RISK ) off with -4LI broadly , some isolated -5 LI and some lovely 1200-1300 J/Kg cape we all must think its a dead cert, but a CAP ( convective inhibition on charts ) will alway be around in high pressure scenarios to spoil the fun. Tomorrow's CAP looks weakest around the -5LI region . SO id go for The Cork , Tipp and surrounding areas for the best chance of anything 2moro.





Monday

Monday looks better again for many with some nice puurty colours on the LI charts , -6 BROADLY and 1500 cape !!
( must check hi res charts to confirm this )

the CAP on monday looks weaker for anywhere inland this time .
I choose inland counties with high ground/mountains that may help trigger some storms.



Tuesday

Tuesday , now if i had a car , i'd be chasing then! , simply amazing values in terms of LI and CAPE , -8 LI with near 2000 Cape !!!

CAP looks weaker again in inland areas but this time storm risk favouring northern areas this time with some better lapse rates on the cards.







Hopefully now we can get some storms to kick off to bring down the humidity over the coming days . If anyone from the Dublin region is thinking of going chasing Monday / Tuesday and would like a storm wingman , pm me :cool::pac:


Now off to get ready for work ...

If the inversion layer stays away for a could part of tuesday , i really do think its worth a chase !! ... Never saw such values in the near term on GFS !!



For those trying to understand the CAP .. hears a picture that may help





Think of it like shaking a coke bottle , all it wants to do is to escape the bottle , but isnt going anywhere with the CAP still on !

This is why seeing LI of -9 on the 0Z GFS was so interesting.

Lower than -7 is very rarely seen in the UK, let alone the smaller landmass of Ireland.



It hasn't been repeated on the 06Z GFS btw.

12Z GFS, Tuesday still looking like the day with the best potential.

LI of -7, up to around 2,000 j/kg of cape. Precip showing up under the area of highest instability.

Wine Goddess wrote: »

Thanks so much - I've only just got my head around the snow jargon so this is a great help!
BTW what does CAPE actually stand for?
(and mean......thanks)

CAPE = Convective Available Potentail Energy . .. Basically it's the strength of uplift of a parcel of air from the surface .

To really see it at its best , America is the place to be , 4000 - 5000 cape on a high risk day , you literally see the clouds explode upwards !

Only just home from work and back it at 5 so can't look at the charts much but nice to see Maqs post with Tuesday still looking nice .

And yes WC ,a good sea breeze may help near costal areas , tryin not to get excited . Ha

Small chance in the south this evening maybe?

At first glance the right ingredients are there. This is more than enough to produce good thunderstorms :



And if all conditions were ideal, there would be no doubt about it :



But those storm risk charts don't take into consideration the strong cap that will prevent cumulus from towering. So unless the cap breaks there won't be anything. Estofex forecast doesn't show anything, so the chances look slim for today.

Storm 10 wrote: »

How come no mention of storms on ME for the week ahead

Low risk because of the strong cap at the moment. And if it does happen would be fairly isolated.

Comparing radar echoes on ME to visible satellite loop on UK Met, the echoes moving southwest in the vicinity of Westmeath and Offaly are not apparently weather phenomena. Flocks of birds or insects? This has happened on occasion with U.S. radars near the Gulf of Mexico.

Possibly just local flocks coming far inland in response to what must have been unusual stimuli in atmosphere and possibly magnetic environment.

Something was definitely moving southwest and it wasn't related to cloud cover. I noticed that whatever it was dissipated over the Offaly-Laois border region around 6 p.m. after travelling steadily southwest from around Armagh and Louth to that position.

As I've seen examples of the travelling shore birds and a postulated insect migration on LCH and s.e. VA radars I have to say it looked rather similar to those. But it may just have been some odd form of radar interference not related to any actual object(s).

Well it does look like the cap will just be too strong this week, the models have backed off now from showing any afternoon/evening precip in the days ahead - so bad news for thunderstorm lovers but good news for heat fans that don't want any showers!

Friday is looking good at the moment on the 12Z GFS. It would be a nice way to finish up this heatwave - out with a bang!

some big storm like looking clouds building to the west of me here. Seems to be convecting from the conemmara mountains.

Weathercheck wrote: »

Wouldn't count out the chance of a small shower exploding through the CAP later in the midlands, GFS has a wee signal for it and added to the huge CAPE values

It's a real shame about the cap! It's like having all the ingredients to bake the perfect cake but not being able to put it in the oven.



Friday looks looking like the most realistic chance on the GFS.

Just a reminder there should finally be all the right conditions for some thunder showers this afternoon & evening in northern / northeastern parts.

highdef wrote: »

Thanks for that. With the cold front approaching and temps so high in eastern areas, I will be keeping an eye on any cloud build up

The action looks like it might be happening a bit further north, but we'll see what happens in a few hours.

First sight of cumulus in 2 weeks!!! Down here in Wexford

Looks like a cell has fired up north west of Enniscorthy

Indeedy, they dp - cells now seem to be firing up in a line inland from the south coast. A lot of CBs are now showing up on sat24, mainly from Tipp to Wicklow. Big cell now on radar just east of Clonmel and another has just appeared to the west. I would expect a lot more activity to appear from now on and through the evening. I'd say the sea breezes are playing a major part in their formation

Iancar29 wrote: »

First sight of cumulus in 2 weeks!!! Down here in Wexford

nimbocumulus :eek:

Rumbles just to the west of us started 5 minutes ago. No visible lightning

Met eireann saying there will be thunder in the east coast, hopefully some sparks.

Shall Friday be d Cap buster?!?.... We can only wait and see!

I wasn't born......