Convective Outlook: Wed 11 Mar 2020
LOW
SLGT
MDT
HIGH
SVR
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Wed 11 Mar 2020 - 05:59 UTC Thu 12 Mar 2020

ISSUED 06:49 UTC Wed 11 Mar 2020

ISSUED BY: Dan

Strong west/southwesterly flow covers the British Isles on Wednesday, with a fairly mild airmass  across southern Britain, while cold air advection persists across northern areas. The net result is a strengthening thermal gradient and the development of a quasi-cold front, which will tend to form an area of more organised showery rain drifting eastwards across Ireland during the afternoon, and then England and Wales late afternoon and through the evening. Given the strongly-sheared environment, broken line segments could develop capable of producing short-duration squally conditions. However, the overall risk of lightning is considered fairly low given weak instability and limited convective depth.

Away from this feature, showers a-plenty will affect many parts of Scotland and Ireland, most frequent in the west with greater proximity to more significant instability (300-600 J/kg offshore). As such, a few sporadic lightning strikes will be possible, especially in western Scotland and perhaps western Ireland. A low-end SLGT has been issued for western Scotland, where the risk of lightning is considered relatively higher, more especially during Wednesday night. Given the fairly strong LLS and backed surface winds, a low-topped supercell could occur almost anywhere (but the risk is considered very low in any one location).