Convective Outlook: Sun 31 Dec 2017
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Convective Outlook

VALID 06:00 UTC Sun 31 Dec 2017 - 05:59 UTC Mon 01 Jan 2018

ISSUED 22:05 UTC Sat 30 Dec 2017


Sharp upper trough will migrate eastwards across the British Isles on Sunday, with cold mid-levels atop SSTs generating deep instability in the post-frontal environment. The cold front first thing in the morning over England and Wales may exhibit some elements of line convection given strong flow parallel to the front in a strongly sheared environment. While this may be capable of a brief spell of gusty winds and heavy rain, in general convection will tend to be too shallow for much in the way of lightning.

Behind the cold front, several shortwaves will approach from the west, providing the focus for scattered showers that may occasionally form more organised lines as they track eastwards across Ireland, Wales and England. Lightning activity will tend to be most frequent over the Celtic Sea and English Channel, and adjacent coastal counties - a bit marginal for an upgrade to SLGT at present. Such deep convection will be capable of strong, gusty winds, small hail and perhaps a tornado.