|Convective Outlook: Fri 22 May 2020|
|What do these risk levels mean?|
VALID 06:00 UTC Fri 22 May 2020 - 05:59 UTC Sat 23 May 2020
ISSUED 08:48 UTC Fri 22 May 2020br> br>
ISSUED BY: Dan
Deep area of low to the west of Ireland will migrate northeastwards to pass close to the Outer Hebrides by Friday evening. Frontal rain will continue to clear eastwards across Scotland and England, although the wrap-around occlusion will feed persistent moist air of tropical origin onto the upslopes of western Scotland, bringing significant rain accumulations. South of the low, a strong southwesterly flow will feed a moist low-level airmass eastwards beneath a markedly dry mid/upper troposhere. Numerous showers are expected in Ireland and southern Scotland, aided by diurnal heating and subtle shortwaves moving through in the flow aloft. Convection will generally be restricted to below 700mb due to a mid-level capping inversion, although may be able to periodically push up to 600mb (ELTs around -20C) as shortwaves temporarily cool the mid-levels. Instability is a little meagre, generally around 100-300 J/kg CAPE, but 30-40kts shear in the cloud-bearing layer may aid in updraft/downdraft separation to sustain cells and produce a few isolated lightning strikes.