Storm Forecast Valid: Fri 15 Aug 2014 06:00 to Sat 16 Aug 2014 06:00 UTC Issued: Thu 14 Aug 2014 22:36 Forecaster: TASZAREK
A level 2 was issued for parts of Russia and Ukraine mainly for tornadoes, severe wind gusts, large hail and excessive precipitation
A level 1 was issued for N Italy, parts of Austria, Slovenia, Croatia, Bosnia and Herzegovina mainly for large hail and severe wind gusts
A level 1 was issued for area from parts of Balkan Peninsula to parts of Russia mainly for large hail, severe wind gusts and excessive precipitation
A level 1 was issued for south-eastern Spain and Balearic Islands mainly for large hail, severe wind gusts and excessive precipitation
A level 1 was issued for parts or North Sea and Baltic Sea mainly for waterspouts.
Most of the European continent is covered by wide long-wave trough that is surrounded by jet stream extending from Spain, through Italy, Balkan Penninsula up to western Russia. Warm and moist tropial air masses are pushed into eastern and south-eastern Europe by extensive cold front on which severe convective phenomena are expected. Overlap of significant vertical speed and directional wind shear with moderate instability will provide perfect conditions for isolated supercells and linearly organized squall lines. Western, central and northern Europe will be covered by polar air masses where internal thunderstorms with low vertical wind shear environment are expected to occur. Mixing ratios around 7-8 g/kg and moderate lapse rates (6-7C/km) will provide rather weak (for this part of the year) instability (CAPE up to 500-600 J/kg). Except local hail up to 1-2cm, waterspouts, and rather weak convective wind gusts no severe weather threats are expected in this area.
Thunderstorms in the homogenius air masses should dissipate in the evening. Convection during night is predicted to be active along cold frontal zone in the eastern Europe and Baltic Sea that due to higher temperature than air above will provide instability.