Storm Forecast
Valid: Tue 09 Jun 2020 06:00 to Wed 10 Jun 2020 06:00 UTC
Issued: Mon 08 Jun 2020 23:09
Forecaster: DAFIS
A level 2 was issued for NW Ukraine, W Belarus, Lithuania, Latvia and Russia for large and very large hail, severe wind gusts and tornadoes.
A level 1 was issued for Russia, Ukraine, Belarus, Lithuania, Latvia, E Poland, Bulgaria, North Macedonia, and N Greece mainly for large hail and severe wind gusts.
A level 1 was issued for Romania, Hungary, Slovakia, E Croatia, Bosnia and Herzegovina, Montenegro, Albania and Albania mainly for excessive rainfall.
A level 1 was issued for Turkey mainly for large hail.
A level 1 was issued for N Italy, SW Austra, S Switzerland and E France for large hail.
A level 1 was issued for NE Algeria and N Tunisia for large hail and severe wind gusts.
SYNOPSIS
A PV streamer extending from Scandinavia towards the Mediterranean over Western Europe becomes thinner, with a strong PVA lobe over France. The associated long-wave trough is surrounded by several waves. A short-wave trough will cross Spain on Tue 09/06, and another one the north coasts of Africa where DMC is expected. East from the trough, the southerly flow has brought moist air masses in Eastern Europe from the Mediterranean Sea. At the surface, an elongated stationary front extends from Russia into the Balkans where severe weather events are expected. Moreover, the Balkans and Turkey will also experience DMC under the influence of short-wave troughs and strong diurnal heating.
DISCUSSION
.... NW Ukraine, W Belarus, Lithuania, Latvia and Russia ....
A strong convergence zone is found along the stationary front in NW Russia and the Baltic States. Widespread lift of unstable air masses, enhanced with moisture from ongoing DMC on Mon 08/06, will lead to numerous of convective cells before 12z. The best chances for supercell development is highlighted by a level-2 area where DLS locally will exceed 15 m/s and 0-3km shear will be stronger than 10 m/s, overlapping with more than 1500 J/kg MLCAPE. Veering profiles are not strong but locally SREH0-3km is expected to exceed 150-200 m2/s2. Storms will be able to produce large or very large hail if they stay isolated. MCSs are as well possible, and clustering storms will be able to travel long distances NE. The high values of SBCAPE (locally more than 2500 J/kg), low LCLs and 5-10 m/s 0-1km shear can lead to tornadogenesis.
Most of the storms will stop after sunset but a few will continue during the night of Tue and early morning of Wed 10/06, becoming elevated with a reduced severe weather threat.
.... Balkans and Eastern Europe ....
Warm and moist air masses lie in this part of the continent, where the wind field is weak in the lowest 6 km of the troposphere. Numerous diurnally driven storms are expected and excessive precipitation will be the main threat, but for the SE parts of the Balkans, a few large hail events cannot be ruled out. Steep low/mid-level lapse rates and high NCAPE create a favorable environment for hail events.
.... Turkey ....
Very steep lapse rates develop over Turkey on Tue 09/06 where CAPE will locally exceed 2000 J/kg. Numerous convergence zones in mountainous areas highlighted by two level-1 areas and strong diurnal heating will help unstable air masses to overcome the morning strong cap. Large or very large hail is possible.
.... N Italy, SW Austra, S Switzerland and E France ....
Diurnally driven storms may get the benefit of 10-15 m/s DLS to organize and produce severe weather events. Apart from solar heating, lift will be provided by an approaching trough from the west, so the surface air masses will most probably overcome quickly the CIN shown in NWP models. Locally large hail events are expected.
.... NE Algeria and N Tunisia ....
The southern flank of the long-wave trough in W Europe is interacting with the tropical air masses in N Africa, resulting in strong baroclinicity and the intensification of a jet stream. This jet will lead to very strong DLS overlapping with some hundreds of CAPE. A few storms may turn into supercells able to produce severe wind gusts and large hail.
