Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest
Convective/Thunderstorm Discussion Autumn/Winter 2018/2019
-
18-09-2018 2:21pm#1
Comments
-
-
-
-
-
-
Advertisement
-
-
-
-
-
-
Advertisement
-
Some convective set up possible tomorrow , sporadic lightning a low possibility, maybe more so over water close to coasts , in the S, SE perhaps, low possibility later in the W ? Heavy rain again along the S tomorrow.
0 -
Convective Weather.co.uk
Day 2 Convective Outlook
VALID 06:00 UTC Tue 06 Nov 2018 - 05:59 UTC Wed 07 Nov 2018
ISSUED 21:25 UTC Mon 05 Nov 2018
ISSUED BY: Dan
A complicated upper pattern exists on Tuesday, with an upper low over the Pyrenees weakening allowing elements of upper forcing to be drawn northwards across the British Isles on the forward side of the main Atlantic upper trough. At the same time, the next Atlantic upper trough will pivot such that it becomes more negatively-tilted as it crosses Biscay on Tuesday night into SW England by Wednesday morning.
Through Tuesday daytime, elements of elevated convection from mid-level instability release will produce some sporadic bursts of showery rain across some central and eastern parts of the British Isles - but similar to Monday, the risk of lightning is considered very low (below 5%), and hence no threat level has been issued.
A series of frontal zones will provide pulses of occasionally heavy rain northwards over Ireland and western Britain throughout this forecast period, which may produce some localised sporadic lightning, but the vast majority will probably remain lightning-free at this point.
The main interest is during Tuesday evening and night as stronger upper forcing approaches, overlapping warm, moist low-levels (and atop warm SSTs), helping to generate 400-700 J/kg CAPE. Cyclogenesis is also expected to occur close to or over SW England, encouraging a wrap-around occlusion to develop. Given this environment, an increase in lightning activity seems likely amongst a rather messy precipitation pattern. Strong gusts of wind and hail up to 1.5cm in diameter will be possible with the most intense cells, while an isolated tornado cannot be ruled out. There is a risk of localised flooding where convergence zones develop across SW England and/or west Wales, providing prolonged heavy downpours.0 -
An interesting forecast for this evening and tonight.
A shortwave trough passes near to the south coast bringing a chance of organised convective cells with some sparodic lightning.
00z
03z
With both good deep and low level shear, some lined squall segments with hail is possible, even a weak funnel cloud.
Pity its due during the hours of darkness, however.
May set the alarm once or twice thought just to have a peak at the radar. :rolleyes:0 -
-
Heavy showers going through here in Kerry. Looks like some good convection from Satellite and cloud top charts show temps of about -40 to -50C . Will see if we get enough forcing to produce a few sparks. Would imagine best potential over the sea near the S and SE coasts, the relatively warm SST's aiding instability perhaps.
Charts showing convective potential at times over the coming days.
0 -
-
-
-
-
-
Advertisement
-
-
Estofex have gone with a level 1 for Ireland today.
The sharp cold front of the Atlantic cyclone will cross Ireland in the 11 to 18 UTC time frame. Forecast models agree on marginal CAPE and a very strong wind field with up to 20 m/s shear and up to 400 m^2/s^2 storm-relative helicity across the lowest kilometer, respectively. Supported by strong lift ahead of the new Atlantic short-wave trough, a cold frontal rainband could form. Severe wind gusts are possible, and one or two tornadoes are not ruled out in case discrete stronger updrafts form within such a line. It is questionable if convection will be deep enough to produce lightning, though, hence only a level 1 is issued.
The cold front will encounter more stable air along its further path over England and Scotland and any remaining convection will gradually weaken. Scattered to widespread, non-convective severe wind gusts are still possible in the warm sector and along the cold front, but they are not reflected by the ESTOFEX threat level scheme.
Scattered postfrontal showers will gradually grow deeper and might produce a little lightning over the Celtic Sea towards the end of the forecast period, but by then the wind field should relax enough to keep the wind gusts below 25 m/s.0 -
-
-
-
-
-
-
-
Advertisement
-
IMO Entering a period of instability in the atmosphere over the next couple of days with the passage of numerous troughs and a colder pool of upper air. Probably mostly seeing sferics over the sea with the relatively warm SST's assisting convection and with a fair amount of shear and high lapse rates. Clear spells helping diurnal heating. Showers moving in a SW to NE surface wind direction mainly falling on S and W coasts that might become weakly electrified and produce some lightning ( probably low chance ) and possible hail. If anything some good cloudscapes with blue skies tomorrow
0 -
-
Parameters there for convection tomorrow but uppers maybe not cold enough to produce enough instability for clouds to become deep enough and become electrified . Clear spells earlier until the occluded front passes over, never great for thunderstorms but perhaps after it under the passage of a trough. Will see.
0 -
-
-
-
Advertisement
-
http://www.convectiveweather.co.uk/
Day 1 Convective Outlook
VALID 06:00 UTC Sun 11 Nov 2018 - 05:59 UTC Mon 12 Nov 2018
ISSUED 21:16 UTC Sat 10 Nov 2018
ISSUED BY: Dan
Broad upper low continues to slowly migrate from the Atlantic towards Ireland, the associated cold mid/upper-levels atop warm SSTs steepening lapse rates and generating 400-800 J/kg CAPE. Once again numerous showers will develop over open seas, then transferring inland to exposed southern and western coastal counties, and occasionally well-inland as organised troughs / occlusions swing through.
Given lack of any notable shear, both SLGTs should be treated as low-end to highlight areas where periods of better forcing may exist - the main interest for S / SE England will be on Sunday morning, whereas for the Irish Sea this is mainly Sunday evening and overnight. In both cases, the most intense cells may produce hail up to 1.5cm in diameter, accompanied by gusty winds. Showers training over the same areas could produce some localised flooding.0 -
-
-
-
-
Advertisement
-
-
-
-
-
Parameters there again for sporadic lightning tomorrow with the passage of an upper trough. Again uppers not very cold and not alot of shear. Best chance for lightning again over the seas and close to the coasts it would seem with a few straying inland.
spookwoman might be in line for good shots again tomorrow
0 -
-
-
-
-
-
Advertisement
This discussion has been closed.
Advertisement