Storm Forecast Valid: Thu 01 May 2014 06:00 to Fri 02 May 2014 06:00 UTC Issued: Wed 30 Apr 2014 23:36 Forecaster: GATZEN
A level 1 was issued for the central Balkans mainly for excessive precipitation.
A level 1 was issued for the northern Aegean mainly for large hail.
Weak geopotential is present across Europe, and the jet stream extends from the Bay of Biscay towards the Mediterranean Sea. Two vort-maxima will travel within the jet, one from Italy to Turkey, the other from the Bay of Biscay to the west Mediterranean Sea. Due to limited moisture over the Mediterranean, CAPE will be rather weak. Further north, moist and well-mixed air masses are still present from western into central and eastern Europe. Widespread convection will result during the period. Colder and dry air masses start to spread south from Scandinavia.
Greece, Aegean region
A short-wave trough moves east during the day, providing DCVA. The affected air mass is expected to become unstable in response to diurnal heating over Greece and onshore advection of modest moisture. Near the trough axis, initiation will be most likely, but weak vertical wind shear will limit storm organization. The best potential will therefore exist across the Aegean region, where an ageostrophic flow will evolve ahead of the vort-max. More than 20 m/s deep layer vertical wind shear are expected by latest GFS model run in the evening hours. Multicells and supercells may be capable of producing large hail. Given weak low-level vertical wind shear, tornadoes are rather unlikely.