Storm Forecast
Valid: Tue 17 Aug 2021 06:00 to Wed 18 Aug 2021 06:00 UTC
Issued: Tue 17 Aug 2021 03:22
Forecaster: DAFIS
A level 2 has been issued for parts of Latvia, Esthonia, Belarus, and W Russia for large hail, severe convective wind gusts, and tornadoes.
A level 1 has been issued for a large part of NE Europe for large hail, severe wind gusts, and excessive precipitation.
A level 1 has been issued for parts of Croatia and Bosnia and Herzegovina mainly of r excessive convective precipitation.
SYNOPSIS
A vigorous short-wave trough in the North Sea is surrounded by secondary waves, all of them associated with the advection of high PV in northern Europe. At the surface, the frontal activity of a low-pressure system in S Scandinavia will be the main synoptic feature in this outlook. A fast-moving cold front is now over Central Europe and travels east, bringing much drier and colder conditions behind it. Another trough in N Italy will provide lift to unstable air masses in the Adriatic Sea and DMC events are expected. A few more places in Europe, Asia and N Africa will experience DMC but severe weather threats will be more limited.
In the Baltic Sea, several waterspouts are expected.
DISCUSSION
.... Latvia, Esthonia, Belarus, and W Russia ....
Several storms are expected in the warm sector of the cold front. Especially in this region, the overlap of high helicity, high CAPE and moderate to strong shear will create favorable conditions for supercells. Isolate supercells will pose a high threat for large hail, while more linearly organized cells will produce severe convective wind gusts and downpours.
High values of 0-1km shear and SREH, along with the very low LCLs, suggest that storms in the Level-2 area will be able to produce tornadoes. One or two strong tornadoes are possible.
.... Croatia and Bosnia, and Herzegovina ....
Under the presence of a surface low-pressure system over Italy, the influx of warm and moist air masses in NW Balkans, the lift provided by a passing-by short-wave trough and steep orography will result in a dangerous set-up for stationary storms. Training convection may result in excessive precipitation where the Level-1 threat has been issued.
