Convective Outlook: Fri 21 Jul 2017
LOW
SLGT
MDT
HIGH
SVR
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Fri 21 Jul 2017 - 05:59 UTC Sat 22 Jul 2017

ISSUED 03:52 UTC Fri 21 Jul 2017

ISSUED BY: Dan

Strong shear along the wrap-around occlusion, coupled with a relatively high WBPT airmass, will allow elements of line convection to be embedded within the main frontal precipitation. As a result, some squally conditions are likely, particularly over Wales, the Irish Sea and SW England, and perhaps later into the W Midlands / W Country / NW England / SW Scotland. In general, convection limited somewhat in depth, as suggested by marginal mid-level lapse rates, so lightning probably fairly isolated, but some strong gusts of wind and perhaps an isolated tornado would be possible given low cloud bases.


In the post-frontal airmass, a messy mix of showery precipitation is expected around the surface low centre over the Republic of Ireland. Sufficient instability will exist for some sporadic lightning, but not widespread and/or frequent enough to upgrade to SLGT - for now. Under such cold-core, slack surface conditions, a few funnels or weak tornadoes/waterspouts will be possible, perhaps also some hail with the strongest cells.