|Convective Outlook: Thu 22 Jun 2017|
|What do these risk levels mean?|
VALID 06:00 UTC Thu 22 Jun 2017 - 05:59 UTC Fri 23 Jun 2017
ISSUED 07:36 UTC Thu 22 Jun 2017br> br>
ISSUED BY: Dan
UPDATE 07:36 UTC Still muted signals as to how much of an increase in convection from mid-levels may occur over SE England and E Anglia this morning, with perhaps the biggest increase in coverage occurring once the main WBPT plume has shifted out across the North Sea / BeNeLux. Better signals for thunderstorms over parts of Lincolnshire and Yorkshire late morning / early afternoon as well-pronounced trough with cold pool drifts east over residual low-level moisture (SMZ) with notably steep mid-level lapse rates
Elevated deep convection (and potential thunderstorms) may be ongoing / will develop more widely with time across S/SE England and East Anglia on Thursday morning as increased forcing on the forward side of the approaching upper trough destabilises the high WBPT plume. The extent of lightning is questionable, so no MDT has been issued for now - and depending on how slowly this zone of convection clears eastwards, there may be scope for some cells to become rooted within the boundary layer. Some hail will be possible, along with strong, gusty winds.
Farther north, beneath the upper trough / vortex, cold mid-levels will rapidly steepen lapse rates to bring the threat of some showery precipitation over N Wales / southern parts of northern England with a few thunderstorms, especially farther east towards Lincolnshire (and perhaps Norfolk) with better surface heating occurring ahead of this feature. Some uncertainty over the speed of clearance into the North Sea, and so no MDT issued for now. A brief funnel or weak tornado may be possible.