Mesoscale Discussion
Valid: Sun 30 Aug 2015 20:00 to Sun 30 Aug 2015 23:00 UTC
Issued: Sun 30 Aug 2015 20:00
Forecaster: GROENEMEIJER

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 storm 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.