A very complex thunderstorm setup where a Spanish Plume will bring a threat of SEVERE thunderstorms to parts of France, Channel Island and southeast England. A very warm Theta-E plume will arrive in parts of southeast England in the early morning, where an upper trough provides moisture for thunderstorms to develop vividly. These thunderstorms will first develop across the English Channel at 03z, then move northeastward into the Isle of Wight, Brighton and Kent over the morning. MUCAPE might exceed 1000 J/kg, therefore thunderstorms are likely to be strong and lively. Strong low and mid-level shear also supports very strong elevated thunderstorms to develop, therefore one or two supercells are likely somewhere in the enhanced risk area. Marginally large hail (2-3 cm in diameter), heavy rain (40-60mm within 6 hours), gusty wind (up to 55 mph) and tornadoes are possible across the severe area ( black outlined area). A high risk has been considered but has been held off due to the unusual amount of uncertainty of the northern extent of thunderstorms between different high-resolution models.
Further thunderstorms are possible across the southeast coasts in the late morning/ early afternoon as another plume of warm Theta-E air mass with moderate CAPE value will arrive. However, these thunderstorms will not be as active as those in the early morning due to the saturated profile.
Elsewhere, scattered showers are likely and might produce sporadic lightning, especially across western parts of Scotland in the afternoon, as well as parts of East Midlands and East Anglia due to the weakening cold front.
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