A level 1 was issued for Serbia and SW Romania mainly for severe wind gusts, excessive rainfall and to the lesser degree for large hail.At mid to upper troposphere, a short-wave trough will quickly move from Corsica across the Adriatic Sea towards Serbia, transforming into a separate low and filling out in the process.
DISCUSSION
... Italy to Balkans ...
Widespread thunderstorm activity is forecast across the region, particularly over the western coastlines of the Tyrrhenian and the Adriatic Sea. As of Sunday 06 UTC, widespread DMC will already be ongoing over parts of the areas, namely Central Italy and the northern Adriatic. This activity may already be severe. During the day, as the short-wave moves eastward, convective coverage will decrease over Central and N Italy and increase over the parts of Adriatic Sea as the storms spread S along the Adriatic coastline.
Across the N Adriatic, main threat will be excessive rainfall given weaker vertical wind shear and slower storm motion. Organisation of convection will increase towards S and well organised multi to supercells are forecast over Central Italy and from S Croatia towards Montenegro. Here, large to very large hail and severe wind gusts will also be possible besides excessive rainfall, given the overlap of CAPE and 0-6 km bulk shear exceeding 20 m/s. From S Dalmatia towards Montengero, NWP also simulates strongly curved hodographs with SRH exceeding 300 m2/s2 in the 0-3 km layer and LCLs below 1000 m. Tornadoes, even strong ones, may accompany supercellular convection over this area. It is likely that a large convective system will eventually form and progress across S Bosnia, Montenegro into Serbia and SW Romania, in conjunction with the passage of the short-wave trough in the overnight hours.
