Convective storms are rapidly developing across west Belgium and the southern Netherlands. With surface dew points in the 20-23 C range, about 2000 J/kg of CAPE should be in place. Strong deep-layer (0-6 km) shear of 20-25 m/s aids in storm rotation, so that
storms quickly acquire rotation as is evident from the hook-echo features on KNMI radar. The storms can produce very large hail, severe wind gusts, extreme rainfall rates as well as a few tornadoes, given that
low level shear should be adequate for tornadogenesis: observed NE surface winds of 5 m/s topped by 10 m/s wind from the southwest at 850 hPa per NWP. Towards the end of the MD period, the storms will gradually become less surface-based and cluster, diminishing the tornado risk.
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