Large upper low continues to sit west of Iberia, with a surface low forming close to a waving frontal boundary across southern Britain on Tuesday. Overall, the risk of lightning in any one location is considered quite low, but two SLGT areas have been issued to highlight zones of slightly better potential, albeit still quite low-end.

A combination of insolation and low-level wind convergence may allow a couple of heavy showers / thunderstorms to form over SW Ireland, before more general showery precipitation arrives from the east later in the day. 

Meanwhile, to the south of a zone of showery precipitation (with embedded convective elements) across Wales - Midlands - East Anglia, some insolation may develop across southern counties of England, and coupled with a very moist low-level air mass and wind convergence, there is potential for scattered heavy showers and a couple thunderstorms here also. However, biggest uncertainties are the extent of cloud cover and whether sufficient insolation can develop to generate deep convection. Furthermore, depending on exact developments with wrap-around process, if cloud breaks do extend farther west towards the SW Peninsula (which is possible), then the SLGT would in theory need to be extended to here also - but current conflicting guidance reduces confidence here somewhat.

Given low cloud bases and low-level convergence, there is potential for a few funnel/weak tornado reports.