Storm Forecast
Valid: Mon 27 Jul 2015 06:00 to Tue 28 Jul 2015 06:00 UTC
Issued: Mon 27 Jul 2015 03:42
Forecaster: VAN DER VELDE
A level 2 was issued for Russia and Ukraine mainly for large hail, severe wind gusts and tornadoes.
A level 1 was issued for S Germany, N Austria, Czech Republic and S Poland mainly for tornado chances.
A level 1 was issued for NE Italy, Slovenia mainly for large hail.
SYNOPSIS
A strong low for the season is situated over the North Sea. Unstable air 100-500 J/kg MLCAPE is associated with it from Netherlands into Poland. Steep pressure gradients on its south and west sides produce a lot of wind. Other lows are found over Norway and N Italy. Relatively weak CAPE with modearate to strong shear are found mainly over the Balkan and NE Italy. Warmer and more unstable airmass (>1000 J/kg MLCAPE) is found from S Ukraine into Russia with moderate or strong shear.
DISCUSSION
...Ukraine to Russia...
Strong instability, around 1500 J/kg MLCAPE, and weak capping are present through an elongated area which sees most forcing over western Russia near a low pressure core and old occlusion point. 10-17 m/s DLS will help clustering and storm rotation. Large delta-theta-e over 20 K suggests major downburst potential. Storm motion itself is moderately fast and an MCS could bring widespread severe gusts. Tornado chances are present with 0-1 km shear over 10 m/s and humid BL in the western part of the level 1 and 2.
...Northeast of the Alps...
A cold front/shortwave trough comes through the Czech Republic and surrounding area around 09Z-12Z with slight CAPE but at the left exit of a jet streak which also causes 20-25 m/s DLS in the presence of spots with 10 m/s LLS and for a slight tornado chance. The instability is marginal so the large hail chances are not so high.
...Southeast of the Alps...
The jet causes 25-30 m/s DLS through a modest CAPE region, but with extreme delta-theta-e. This may produce heavily sheared storms which if resist being torn apart, may become supercells with some large hail and severe gust chances.
