Mesoscale Discussion #003 (valid 19/05/2014 13-18 UTC)

Thunderstorm initiation is underway over the MDT risk area in SE Ukraine. Latest sfc data show temperatures in the 28-32 °C range with dewpoints between 12 and 19 °C. Strongly backing 10-20 kt SE-E winds are present. A 30-40 kt 500 mbar SSE jet produces a moderately sheared environment with 30 – 40 kt DLS. Strongly veering vertical wind profiles with 200 – 350 m2/s2 SREH3 are very favourable for supercells. The highest probability of supercells is along a relativly narrow coridor ahead of the cold front where very favourable winds overlap with up to 2000 J/kg MLCAPE. QG forcing is limited, somewhat reducing storm coverage. Main threats with thunderstorms in this area are large to very large hail, severe wind gusts, locally strong convective rainfall and tornadoes. Tornado threat is particularly maximized over CNTRL Ukraine and Russia east of the Sea of Azov, where strong LLS (up to 30 kt) and SREH1 (up to 200 m2/s2).