A level 1 is issued for wide areas between Italy, S Finland and Romania, and a level 2 for parts of Austria, the Czech Republic, Germany and Poland mainly for excessive convective precipitation and large hail, and to a lesser degree for severe convective wind gusts.
DISCUSSION
... European level 1 and level 2 areas ...
The warm and moist airmass under rather cyclonic influence and weak dynamics allows the buildup of mostly moderate CAPE after some hours of diurnal heating (mostly in the 500 to 1000 J/kg range, regionally less or somewhat more). Scattered to widespread, disorganized, daytime-driven thunderstorms will again form over orographic features, along outflow boundaries, insolation gradients, other (diffuse) convergence zones, and ahead of travelling upper-level vorticity maxima. Single cells, some multicells and larger clusters are the expected convective modes. The primary hazard is excessive rain, while the strongest pulse storms can also bring marginally large hail, plentiful small hail and/or isolated severe downbursts. Parts of Austria, the Czech Republic, SE Germany and W Poland are upgraded to a level 2, since convergent near-surface winds and weak synoptic lift (both from warm air advection positive vorticity advection) under fairly robust CAPE hint at a particularly high storm coverage.
Quelle: ESTOFEX (
https://www.estofex.org/)