Storm Forecast
Valid: Tue 27 Mar 2018 06:00 to Wed 28 Mar 2018 06:00 UTC
Issued: Mon 26 Mar 2018 21:57
Forecaster: DAFIS

A level 1 was issued for NE Greece, SE Bulgaria and NW Turkey mainly for severe wind gusts, large hail and excessive precipitation.

A level 1 was issued for S Russia mainly for large hail, severe wind gusts, and tornadoes.

SYNOPSIS

A long-wave trough covers the largest part of Europe, with several embedded short-wave troughs. One of them is currently found in N Balkans and another wave will cross C Europe tomorrow afternoon providing lift, in addition to the lift due to diurnal heating (wherever possible). Several pulsating storms will form in C Europe, Italy and the Balkans, but thermodynamics will not support severe DMC, except large amounts of small hail from slowly-moving storms. The southwesterly jet above the Aegean Sea will remain almost unchanged on Tuesday. Severe weather events are expected in SE Europe, below the jet stream.

DISCUSSION

.... NE Greece, SE Bulgaria and NW Turkey ....

The ongoing clusters of storms will gradually lose their structure in NW Turkey by the morning of Tuesday. We expect a new round of thunderstorms in the afternoon when diurnal heating will provide lift to unstable air masses and strong DLS will assist storms to cluster. CAPE is forecast about 500 J/kg, so hail should not exceed 2cm but large amounts of small hail may also pose a threat. The low-level wind field is weakening but still, severe wind gusts could form within the strongest cells.

.... South Russia ....

The advection of PVA over the north side of Caucasus, along with very steep lapse rates, moist PBL, and a strong mid-level jet suggest that thunderstorms will become severe. NWP models show the movement of a short-wave trough in the afternoon when the storms will be able to cluster in MCSs or become supercells into this strongly-sheared environment. The main threat will be large hail and severe wind gusts, but LL looped forecast hodographs increase the probability of tornadic events. Convective activity should stop during the night.