|Convective Outlook: Wed 05 Aug 2020|
|What do these risk levels mean?|
VALID 06:00 UTC Wed 05 Aug 2020 - 05:59 UTC Thu 06 Aug 2020
ISSUED 06:36 UTC Wed 05 Aug 2020br> br>
ISSUED BY: Dan
As the forward side of an upper trough, and associated PVA / divergence, engages with a frontal boundary this will lead to increasing instability as cool, dry air aloft overspreads a warm, moist low-level airmass. Consequently embedded deep convection is possible, bringing the risk of sporadic lightning across southern Ireland and the Celtic Sea during Wednesday morning (15-20% chance), heading across the Irish Sea towards Wales and NW England - however, by this stage the upper trough will be relaxing, and so there is likely to be a weakening of activity as it approaches western Britain. Nonetheless, a few isolated lightning strikes will still be possible into the afternoon hours associated with the passage of the trough - primarily W + N Wales into northern England (10-15% chance). A few isolated lightning strikes will be possible elsewhere from weak embedded elevated convection, but the risk is considered fairly low (5-10%).