Convective/Thunderstorm Discussion 2013/14

Harps

Very heavy rain here at the moment as well

lolie

tylercollins wrote: »

Nice squall line developing on west of Ireland travelling East/North East.

Something simular on the radar earlier but fizzled out as it crossed the country. If this holds together it could be rough in the northeast after.

sunbabe08

Wow. Just when I thought it couldn't get heavier. Biblical rain falling in youghal

Gonzo

first dry day we've had here in ages, 21C and sunny, better make the most of it, next 2 days are gonna be very wet indeed.

tylercollins

lolie wrote: »

Something simular on the radar earlier but fizzled out as it crossed the country. If this holds together it could be rough in the northeast after.

Still going strong but has fizzled out in the North of Northern Ireland. Seems to be moving more easterly now.

lolie

Pic of the squall/shower passing of the lake earlier. Was like a wall of water approaching.
Looks like it produced a few sparks in the northeast.

Trebor176

We just had a heavy shower in Clondalkin. It's windy, I think it's slightly chilly. It looks like the sort of weather over the last few days is behind us.

acassells80

Heavy rain falling in Dublin 1 and temp has dropped to 18

dopolahpec

Trebor176 wrote: »

We just had a heavy shower in Clondalkin. It's windy, I think it's slightly chilly. It looks like the sort of weather over the last few days is behind us.

I'm not so sure. I think it is to get a bit more convective again tomorrow and thursday, I'm hoping against hope to see some sort of higher pressure regime reestablish itself then. There's still several weeks of potential warm weather left.

maquiladora

Looking at the 12Z GFS... tomorrow morning/afternoon looks like a chance of something interesting in the south-southwest.

Decent lift (-4) with CAPE up to 1,000-1,200 j/kg. What makes it more interesting is about 20 knots of lower layer shear and 35-40 knots of deep layer shear. Add ~40mm of precipitable water and ~250 m2/s2 SRH.

Too early to look at Thursday/Friday in detail but could be more interesting, especially for western areas. I'll be at the Blur gig Thursday night so I'm hoping things stay dry in the east anyway. :rolleyes:

As an example for Thursday, showing a risk of up to 1.5 inch (ping pong ball size) hail along the west coast :

RobertKK

maquiladora wrote: »

Looking at the 12Z GFS... tomorrow morning/afternoon looks like a chance of something interesting in the south-southwest.

Decent lift (-4) with CAPE up to 1,000-1,200 j/kg. What makes it more interesting is about 20 knots of lower layer shear and 35-40 knots of deep layer shear. Add ~40mm of precipitable water.

Too early to look at Thursday/Friday in detail but could be more interesting, especially for western areas. I'll be at the Blur gig Thursday night so I'm hoping things stay dry in the east anyway. :rolleyes:

They were incredibly lucky in Kilkenny with the Bruce Springsteen concerts on both days.
Hopefully you have the same luck.

MrFrisp

sunbabe08 wrote: »

Wow. Just when I thought it couldn't get heavier. Biblical rain falling in youghal

Was that just a shower,,or is it still going?
.

sunbabe08

MrFrisp wrote: »

Was that just a shower,,or is it still going?
.

It last about a half hour

MrFrisp

sunbabe08 wrote: »

It last about a half hour

Thank you.

Getting very dull in the City now..Plenty rain forecast for the next day or two.
.

MiNdGaM3

Thought ye folks might like this. It's a panorama image looking from west to north east, toward the Cork/Limerick/Tipperary border near the Galtee Mts.
It's from the early evening of the 28th.

http://i.imgur.com/5MWxw74.jpg

Oscar Bravo

Very same in Castlebar! was just gona post a pict! its lovely.

Mez1982

Not sure I'm even posting this in the right thread so apologies in advance but I'd thought I'd share this beautiful sunset from Edenderry took with an iPhone but it doesn't do it justice ! Also sorry about the angle but I had some neighbours kids out on their wall and didn't want to have to explain why I was out at 9:00pm taking pictures in their direction!

Sry had to edit as I thought the pic size was too big.

fryup

class ^^

maquiladora

18Z GFS looks very interesting for the west on Thursday.

Lifted Index : Up to -7
SB CAPE : Up to 1,300
MLCAPE : Up to 1,000
DLS : Up to 60 knots
Total Totals : 56

It's rare you see that type of lifted index and CAPE combined with very strong shear in Ireland.

It's only one run of one model and 2 days away, and I have a feeling that will downgrade but really worth keeping an eye on.

maquiladora

18Z GFS for Thursday. Large area of 4-6 cm hail over the west.

Estofex parameters for "severe" includes hail above 2 cm and "extremely severe" is above 5 cm. (In the US, a storm is classified as a severe thunderstorm if hail is larger than 2.5 cm)

So that should give you an idea of the type of storms that would develop if that model was right.



Just worth keeping an eye on for the moment.

squarecircles

a pic from Sunday on the west coast of Mayo as the thunderstorms passed to the north east .

squarecircles

I'v been watching the angry storm clouds all week in Louisburgh Co. Mayo as they past to my east as they develop and drift inland. I have yet to experience any thunder or lightning.:pac:

snowstreams

maquiladora wrote: »

18Z GFS for Thursday. Large area of 4-6 cm hail over west...

Has anything like that ever happened in Ireland? What's the largest hail ever recorded in Ireland I wonder?

maquiladora

One more from the 18Z GFS output (before things downgrade on the 0Z )

One for Iancar to print and hang on the wall maybe.

maquiladora

snowstreams wrote: »

Has anything like that ever happened in Ireland? What's the largest hail ever recorded in Ireland I wonder?

Yes, large hail from the July 1985 storms caused millions in crop damage and killed farm animals/birds. It rarely happens here, but it can happen.

Rikand

Mez1982 wrote: »

Not sure I'm even posting this in the right thread so apologies in advance but I'd thought I'd share this beautiful sunset from Edenderry took with an iPhone but it doesn't do it justice ! Also sorry about the angle but I had some neighbours kids out on their wall and didn't want to have to explain why I was out at 9:00pm taking pictures in their direction!

Sry had to edit as I thought the pic size was too big.

twas awesome alright. took a few photos and videos myself that dont do it justice either. if i could just get them transferred off my phone to the computer, I have about 30 pics and vids of sunsets I could upload onto the thing.

but it had those awesome colors to the north and then a red/purple glow to the south. Was awesome

squarecircles

this evening...

maquiladora

Before whatever happens on Thursday, there is also a small chance of something interesting happening tomorrow (Wednesday) in the southern half of the country.

The UKASF forecast is out :

http://ukasf.co.uk/storm-forecasts/265

Synopsis:
A sharpening upper trough over the Atlantic amplifies the jet pattern, forcing the jet and a surface frontal zone to move progressively northwards across the British Isles. Behind the front, a very warm, moist airmass is advected northwards, particularly across England and Wales.


Discussion:
Behind more general stratiform rain along the warm front, increasing insolation in the warm, humid airmass will build 500-800 J/kg SBCAPE across the shaded ISOL areas. There appears to be a small zone of opportunity, beginning across the West Country/SE Wales and also W Munster around noon, and shifting progressively northwards and eastwards with time towards the northern extent of the ISOLs by 17z-18z onwards; to the south, this will be replaced by continuous warm air advection in the lower levels, providing a significant cap which will continue to shift northwards through the afternoon and evening.

Within the ISOL and to the south/behind the surface front, if any sufficient insolation can develop and utilise the available CAPE there is scope for a few scattered showers or thunderstorms to form during the afternoon and early evening hours, in an environment of 40-50kts DLS enabling such cells to become well-organised. Low LCLs and a favourable vertical wind profile on forecast soundings suggest the potential for an isolated tornado event, the risk greatest if cells can form immediately behind the surface front where low-level flow will be increasingly backed (albeit with more excessive cloud likely to be present). Indeed, with close proximity to the surface front, there may be the (rather low) potential for a low-topped supercell to develop.

Given the degree of uncertainty currently, especially since there is some inter-model disagreement on timings of front clearance, we remain with an ISOL threat for now, but with the potential to upgrade to SLGT during Wednesday as and when necessary.

Redsunset

level 1 was issued for Ireland mainly for heavy rain, severe wind gusts and tornadoes. An isolated large hail event is possible, too.

http://www.estofex.org/

maquiladora

Estofex have put out two Level 1 forecasts for Ireland. The first is for today, the other is an advance extended forecast for Thursday. First time I've seen Ireland in an extended forecast.

For today, keep an eye on the southwest first to see if something starts to develop behind the warm front this morning.