Convective Outlook: Mon 10 Feb 2020
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Convective Outlook

VALID 06:00 UTC Mon 10 Feb 2020 - 05:59 UTC Tue 11 Feb 2020

ISSUED 21:46 UTC Sun 09 Feb 2020


Strong west-northwesterly flow covers the British Isles throughout Monday, advecting markedly cold air from Arctic Canada across the Atlantic. This will create an environment with very steep mid-level lapse rates, especially from Monday evening onwards as the real cold air aloft arrives, yielding 300-600 J/kg CAPE in response to SSTs. As such, numerous showers will develop over open waters and plough inland on strong steering winds, merging to give longer spells of rain (and snow) at times as organised troughs and occlusions swing through in the flow.

The greatest risk of lightning will be over open waters and near western coasts, with an uptick in activity likely during Monday evening and night over parts of N / NW Ireland and W / SW / NW Scotland. Hail is likely in many of the showers, with snow on hills and increasingly to lower levels during the evening and night hours. Despite weaker instability and more limited convective depth across S Ireland / C + S Britain, the environment will be strongly sheared and hence favourable for low-topped supercells. Strong gusts of wind will accompany many of the showers, with gusts of 70-80mph possible along exposed western coasts (especially W Ireland).