[QUOTE]On the forward flank of an area of elevated convection that moved northward over Western France, convective storms have intensified after 16 UTC and evidently become surface-based.
The environment in which these strorms develop is characterized by ample MLCAPE (2000-3000 J/kg), and strong (20 m/s in the west) to moderate (10 m/s in the east) deep-layer shear. The most intense storms will likely occur in across far NW France in vicinity of a prexisting convergence zone (near a line from just south of Rouen to Lille). Given the strong CAPE, very large hail will be possible. The storms may well develop into a bow-echo capable of producing gusts > 32 m/s. A threat of tornadoes will exist if a storm can interact directly with the sea-breeze front.
The western flank of the convective system may also affect W Belgium and SEern England around 20 UTC. [/QUOTE]
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