For the most part, shear is relatively weak and instability lower than Thursday, suggesting that lightning will be fairly isolated and hence the risk is considered just below SLGT threshold (20-25%). Convection may become particularly focussed during the afternoon and early evening along a pronounced low-level convergence zone stretching from SW Scotland across northern England towards Lincolnshire. 

Profiles from south Wales / south Midlands southwards into southern England will be drier and increasingly subsided, suggesting any showers here will be more isolated and generally not as deep. However, shear will increase here later in the afternoon and into the evening, and so any showers that do manage to develop could still produce a few isolated lightning strikes - particularly in SE England - but it will be somewhat of a fight between increasing shear and gradual reduction in convective cloud depth. Showers will weaken and reduce in number during Friday night, but are still likely to persist in places due to both proximity to the upper low and old occlusion debris.