Convective Outlook: Fri 10 Jul 2020

LOW SLGT MDT HIGH SVR

What do these risk levels mean?

Convective Outlook

VALID 06:00 UTC Fri 10 Jul 2020 - 05:59 UTC Sat 11 Jul 2020

ISSUED 07:10 UTC Fri 10 Jul 2020

ISSUED BY: Dan

Upper trough will migrate southeastwards and clear from England and Wales during Friday, but sufficiently close proximity to coincide with diurnal heating and bring the threat of deep convection. At the surface, a boundary is likely to become established from northern England down to East Anglia, with low-dewpoint air and a brisk northwesterly wind to the west, and much lighter winds with higher dewpoints (10-12C) to the east. This will be reinforced by a developing onshore sea breeze along eastern coastal counties, and will therefore provide the main focus for forced ascent. Scattered showers are therefore likely across eastern England in particular, some perhaps reaching tops to 18,000ft (ELTs -25C). Bulk shear will be strongest over East Anglia / Home Counties (20-30kts) but gradually reducing through the afternoon as the forward side of the upper trough clears southeastwards. Nonetheless, the strongest cells could produce a few sporadic lightning strikes, although confidence is not quite high enough to introduce a SLGT at this stage. Some small hail will be possible in places, while a couple of funnel clouds (or weak tornado) could develop where low-level convergence enhances vorticity - more especially Lincolnshire into East Anglia.