Convective/Thunderstorm Discussion: Autumn/Winter 2017-18

Just a couple of sferics showing up last night near Dunmanway and Birr.

zerks wrote: »

Any reports from North Wexford/South Wicklow. Gone really dark up that way.

The conditions today are not conducive for Convection / Thunderstorms. Potential for patchy rain and drizzle is forecast.

Today's detected sferics.

Makapakka wrote: »

Any more due tonight?

Maybe a few on Northern coasts.

Met Eireann : Wednesday: Cool, with a mix of sunny spells and showers, many of the showers will be heavy, some possibly of hail and there is a risk of scattered thunderstorms, especially in the north and west

IMO In a brisk NW'ly airflow over warm SST's with the passage of an upper trough and cold mid and very cold uppers producing big heavy showers, potential for enough forcing to give large high convection producing hail and scattered thunderstorms. Decent CAPE values and a fair amount of DLS with the Jet nearby. Very high lapse rates. Could be interesting .

Not much widespread activity but a good few sferics detected between Clonmel and Waterford. Showers throughout the day here around Tralee and some very heavy ones in the afternoon with a trace of hail in them. Big fluctuations in temperatures during the showers.

Thurs looks like having some potential for convective shower activity possibly in the W and NW I would think as we will be under the influence of an upper trough and cool air aloft with SW'ly surface winds. Some showers perhaps weakly electrified.

( I swear I didn't read this first before making my post above )


http://www.convectiveweather.co.uk/forecast.php?date=2017-09-21





Day 2 Convective Outlook
VALID 06:00 UTC Thu 21 Sep 2017 - 05:59 UTC Fri 22 Sep 2017

ISSUED 20:09 UTC Wed 20 Sep 2017

ISSUED BY: Dan

Sharp upper trough pivoting NE-wards across Ireland and W Scotland on Thursday will provide the focus for deep convection as cold mid-levels overspread relatively warm SSTs and diurnal heating inland, steepening lapse rates and generating a few hundred Jkg-1 CAPE. A low-end SLGT has been issued where there is a better overlap of these variables, with scattered showers and a few thunderstorms likely on Thursday afternoon and early evening, the focus shifting mainly to coastal areas of western Scotland by Thursday night. One inhibiting factor will be quite dry profiles in the mid/upper levels, which may result in more isolated shower distribution - but given steering flow, an individual shower should cover some distance, and therefore increase the potential in lightning coverage. Hail to 1.5cm in diameter is possible from the strongest cells. Relatively high cloud bases (given 6-11C dewpoint depressions) should limit the funnel potential somewhat.

Met Eireann mention 'FRIDAY: Nice spells of autumn sunshine to begin, however it will become breezy with heavy possibly thundery showers moving in across the western half of the country'.

Upper vortex with very cold upper pool of air and looks like a lot of shear from the jet available. Cape and lapse rates should be reasonable.