Convective/Thunderstorm Discussion: Summer/Autumn/Winter 2014-15

Hal1

Seen a wall cloud over city west and funnel or lowering at least very close to the ground. I pulled in a few times but could not get a decent pic due to trees and whatnot. I drove up around blessington lakes but was just met with a torrential downpour. I would have been to the north east of the above pics.

Larbre34

Some rumbles of thunder in Aughrim, Wicklow. Dry so far.

Penname

Sky coming to life over North Kildare. Ten rumbles so far. Camera ready! Woo hoo!

ninebeanrows

Big gusts with the arrival of this shower here. Skies look menacing.

Hail now.

Lady_North1

Thunder and hailstones over Swords a little while ago. Not enough though.

sunbabe08

But of course the east coast gets all the action. Not a peep in tramore except heavy rain

tylercollins

If you're easily offended with bad language then I'd advise you NOT to watch either of these videos!

Large hail storm over Derry this afternoon around 2:30PM.

Hail 1cm - 1.5cm large.



Most impressive thing I've witnessed weather wise so far.

https://www.youtube.com/watch?v=vzmBPNsIHkk

https://www.youtube.com/watch?v=ME6NUOtSPU8

fleet_admiral

My brother was taking part in a regatta in Skerries today. He was telling me there was some fork lightening

Video

tylercollins wrote: »

If you're easily offended with bad language then I'd advise you NOT to watch either of these videos!

Large hail storm over Derry this afternoon around 2:30PM.

Hail 1cm - 1.5cm large.

Was probably this cell around 2.35?

tylercollins

Yeah that's the very one. I was meant to screenshot that, cheers

whitebriar

Thunderstorm here south of Arklow at the moment

Kermit.de.frog

Decent opportunity for a few strikes and some more hail locally this afternoon particularly midlands, east and north as convection gets going. Some nasty downpours around.

pad199207

A good bit away but some great potential for the end of the week

SEPT 23 1989

BBC Countryfile forecast last night said there would be disruption on Friday and they had it tracked moving up over the South East of Ireland

Larbre34

Yes BBC reiterating that this morning, using the technical term 'humdingers" to describe potential storms, although that was mainly for the south of England.

Will be a very interesting weeks of watching to see what, if any, scraps we can pick up from the continental flow. If there are two things that get the forum hopping they are storms and s*** (never in July;))

maquiladora

Not sure we'll see anything special over here, it's too far away yet to know the exact positioning of the low. We'll probably be too far west to get any significant heat from the plume but low-20's do look possible, so it'll feel warm even if storms don't materialize.

Kermit.de.frog

I think there is a very high risk of storms materialising - both inland convection and some goodies from Biscay should do the trick. Only broad outline of risk areas can be given at this stage though but I have a good inkling about the end of the week. I think we will see some action and potential for some big storms by our standards. Very warm, humid and unstable air. It's all there

I'm looking forward to it.

Storm 10

On the forecast on radio at lunchtime Joan said to keep a watch on the weather forecast as they will probably be putting out warnings for the weekend about thunderstorms.

Harps

People starting to get excited here already with the met mentioning thunder on Friday since yesterday. A good chance of a classic Spanish Plume setup but all far too early to nail down specifics so it could still be anywhere from Ireland to Germany that get the storms

Video

GFS is showing -10 - 11 LI in some places on the continent - downgrade for us for homegrown storms though but if something drifts in from south east it could be intense! Will keep checking the 00 and 06 runs of the GFS because the others are always wrong.

maquiladora

Couple of days away so changes can still be expected, but the south of England is looking like the prime location for storms to pop up overnight Thursday into Friday morning with the possibility of an MCS crossing the channel from France.



For Ireland, looks like a moderate risk of storms later on Friday. Doesn't look like being any more significant any previous stormy days this year. Still a few days away though, so subject to change. It should feel quite humid at times too though obviously not as warm as over in the UK since the plume looks set to mostly miss us.

Iancar29

I think Maq , that theres a good chance of high based MCS hitting here too , thursday night into early friday could .


NMM-18 km


Decent Mid level instability

PPN


Warm , moist airmass moving into the south ...


Strong low level shear and good deep layer shear , will give some fairly hefty downpours and the chance of some funnels if anything can become surface based for a time.





Shall be interesting to keep an eye on indeed ...

maquiladora

Would love to see an MCS here Ian but I think that heavy precip shown above is due to the triple point of the low rather than the model predicting an MCS. Could well be some embedded thundery activity within it though.

Iancar29

Would be a high end level 2 Estofex alert for England and wales if the models locked in on this ....


Met Office on the ball already it seems..

Issued at:
1204 on Tue 15 Jul 2014

Valid from:
0300 on Sat 19 Jul 2014

Valid to:
2355 on Sat 19 Jul 2014

Areas of heavy, thundery showers may develop over England and Wales from early on Saturday before moving northwards during the day. The development of these is uncertain but where they do form some torrential downpours are possible with frequent lightning, hail and locally strong gusts. Significant flooding is possible where these do occur from surface water as well as small, fast responding watercourses. The frequent lightning, hail and strong gusts could also be an additional hazard. The public should be aware of the risk of disruption from any of these elements. This alert is likely to be updated in the coming days.

Chief Forecaster's assessment

Following a build of very warm and humid air from mid-week onwards there is the potential for the development of large thunderstorms over England and Wales from early on Saturday. In this situation large amounts of energy are available in the atmosphere and this coupled with high moisture content can lead to torrential downpours along with frequent lightning activity, hail and locally strong gusts. In this situation many elements need to come together at the same time to form these thunderstorms and so there remains large uncertainty in their development. This alert is therefore likely to be updated in the coming days.

maquiladora

Could get up to around 25 in the west on Thursday. Nice. :cool:



By Friday though we are back down to high teens to low 20's which is pretty much par for the course this summer. So nothing exceptional there in terms of heat but Thursday looking very nice for western parts.

You can see the effect of the plume on the continent and UK, just too far east for us.



Best of the CAPE on Friday looking like mid to high hundreds with LI up to around -3, so enough for a few storms to pop up, but nothing severe if this were to verify.



Saturday looking a bit better at the moment, but thats further away again so even more susceptible to change.



Finally, precip accumulation is nothing to write home about on the 12Z GFS. Around 5-20mm over the next 4 days, though theres little point at looking at these kind of charts beyond 24 hours since they can change so much.

maquiladora

12Z ECM showing +20 850 temps reaching southeast England on Saturday! Meanwhile in Ireland...

Hopefully whenever the next plume comes along it heads a little more in our direction. :cool:

maquiladora

Latest WRF showing huge CAPE for northern France on Friday, up to 4,200 J/kg.

Iancar29

I'm still keeping an eye on tomorrow night , friday morning . High based storms making there way into the S and SE . Some very heavy downpours can be expected there with theta E values in the 30s!


Friday day fairly messy for us , TS risk shifts to the west and midlands mainly, but wherever thunderstorms can fire , supercell characteristics are possible . Large hail , frequent lightning and possible funnels/ weak tornado .

Saturday then more of a risk the East and north for some surface based storms , lacking shear though that day for anything severe IMO.

maquiladora

For early Friday, a bit of a western shift on the models since yesterday. South of England still the prime location but now a moderate risk of some thundery rain reaching the south coast area here in the morning.





Later in the day then the risk of thundershowers extends to western and midland areas.

Saturday now doesnt look very interesting for Ireland but showing good potential for severe storms for eastern England.

Still all subject to change.

maquiladora

It will feel very humid Thursday night into early Friday morning as the western flank of the plume brushes us. EURO4 is showing 850 temps up to 14, and surface temperatures of up to 21 degrees - at midnight with 95-100% humidity. Kick off the duvets. :pac: