Convective Outlook: Tue 14 Jun 2016
LOW
SLGT
MDT
HIGH
SVR
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Tue 14 Jun 2016 - 05:59 UTC Wed 15 Jun 2016

ISSUED 11:15 UTC Tue 14 Jun 2016

ISSUED BY: Dan

UPDATE 11:15 UTC Minor adjustments made to SLGT based on latest guidance. Still potential for parts of Ireland to be upgraded to a SLGT, but extensive cloud cover here so far today raises uncertainty as to how much lightning may occur. Most of the activity today will likely be focussed along a sharpening convergence zone from N Wales - Midlands - northern East Anglia where a few funnels or a weak tornado will be possible

Broad upper trough continues to sit over the British Isles, while on Tuesday a surface low will slide eastwards from the Irish Sea to the Midlands. Once again, old frontal boundaries will continue to provide a messy mix of dynamic precipitation and excessive cloud cover, rotating around the area of low pressure. However, they also provide useful convergence zones which, with the help of daytime heating, could generate deep convection with the potential for heavy, slow-moving showers and perhaps a few thunderstorms.

Forecast profiles remain fairly saturated and hence it is questionable as to how much lightning activity there will actually be - despite better instability to be found across north Wales / north Midlands towards The Wash, slightly drier profiles are signalled across southern England and so it may be here that has the true best potential for lightning. Considered a marginal/low-end SLGT for now, but with perhaps relatively better potential compared with Monday. In either case, wind shear is fairly weak and so cell organisation is unlikely, and the threat of severe weather is low aside from the ongoing risk of temporary local flash flooding.

Low cloud bases around convergence zones will bring the risk of a few funnels or even a weak tornado. Parts of central Ireland have the potential to be upgraded to SLGT, but for now concerns over extent of cloud cover preclude an upgrade at this time.