Convective Outlook: Sat 03 Aug 2019
LOW
SLGT
MDT
HIGH
SVR
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Sat 03 Aug 2019 - 05:59 UTC Sun 04 Aug 2019

ISSUED 07:51 UTC Sat 03 Aug 2019

ISSUED BY: Dan

Upper ridge over eastern Britain will gradually weaken on Saturday as heights fall aloft in advance of the approaching Atlantic upper low. Diurnal heating may help yield 300-500 J/kg CAPE across western Britain by Saturday afternoon, by which stage profiles will gradually moisten with depth. Low-level convergence and orographic forcing could lead to the development of scattered showers, and perhaps one or two thunderstorms. Profiles exhibit a fairly substantial warm nose between 500-700mb which may restrict convective depth somewhat, and combined with fairly weak shear would suggest the risk of lightning is somewhat limited despite the likelihood of scattered heavy showers. Main focus appears to be over north Wales and NW England, but confidence is not high enough to introduce a SLGT.


Meanwhile, an occlusion moving gradually northwards and eastwards across Ireland, and across the Irish Sea on Saturday night, may contain some embedded elevated convection, although weak instability suggests any lightning activity will be fairly isolated - greatest threat appears to be E / SE Ireland and adjacent sea areas on Saturday evening. Confidence on lightning activity is not particularly high, but a low-end SLGT has been issued to highlight the main area of interest.