Convective Outlook: Fri 19 May 2017 |
|
What do these risk levels mean? |
Convective Outlook
VALID 06:00 UTC Fri 19 May 2017 - 05:59 UTC Sat 20 May 2017
ISSUED 04:07 UTC Fri 19 May 2017
br> br>ISSUED BY: null
An upper trough will continue to slowly progress from west to east across the British Isles. Lapse rates will decrease across Ireland, but a weak occlusion could just trigger a few heavy showers with a low end lightning risk during the mid afternoon (mainly across central/southern Ireland)
However, instability and lapse rates will increase across the low risk area in southwestern Britain as the upper trough moves near. CAPE of around 500 j/kg and surface to 500mb lapses reaching into the low 40s will help to trigger scattered heavy showers. It is expected that a few of these showers will contain some small hail and typically infrequent lightning as storms will generally be pulse variety with very little shear present.