Convective Outlook: Thu 12 May 2016
LOW
SLGT
MDT
HIGH
SVR
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Thu 12 May 2016 - 05:59 UTC Fri 13 May 2016

ISSUED 17:54 UTC Thu 12 May 2016

ISSUED BY: Dan

UPDATE 17:54 UTC SLGT removed from W Ireland, SLGT over SW England also shifted eastwards a little in light of recent developments

Remnant convection will likely be ongoing across S / SW England first thing on Thursday morning, this clearing westwards to give sufficient insolation to develop isolated showers, more especially late afternoon into the early evening where low-level convergence (onshore flow plus topographical forcing) aids development. Forecast profiles suggest drying and warming aloft from the east through the day, therefore limiting depth of convection and resulting with the deepest instability becoming increasingly confined to the far SW. 

Lapse rates are once again fairly poor, despite high CAPE values forecast given relatively high dewpoints, and hence lightning will be fairly isolated (generally sub-SLGT criteria) with the main threat being local flash flooding from slow-moving heavy downpours in a high PWAT environment (high 20s mm). The strongest cells may perhaps produce hail up to 1.0cm in diameter, while relatively low LCLs and low-level convergence could once again produce a couple of funnels / weak tornadoes. Isolated elevated convection may affect parts of SE England on Thursday night.