Skywarn Austria Forum

A level 2 was issued across parts of Austria into extreme N/NE Italy mainly for large hail and excessive rain.

Both level 2 areas are surrounded by level 1 areas with similar hazards but with lower probabilities. In addition a few severe wind gusts are possible over Austria.

... N Italy into Austria ...

Once again, a passing wave interacts with a moist/unstable air mass and creates a favorable environment for organized convection.
Models keep CI mainly along the orography next to the passing wave with strongest forcing. Although CI is less likely further S over N Italy, not much capping and some QG forcing also affects this area during peak heating. One caveat will be the intrusion of drier (downslope) air from the W.
Kinematics remain excellent with DLS in the 25-30 m/s range and 0-3 km shear approaching 20 m/s in a few places (especially within the level 2 area). Strong veering with height and increasing strength of the background flow create elongated and curved hodographs.

CI is forecast beyond noon with a mix of multicells/supercells. One concern is the intense 0-3 km moist 20 m/s inflow into these cells, which supports temporal back-building and excessive rain. Otherwise, numerous rotating updrafts contain large hail and severe wind gusts. Main limiting factor for a more robust outbreak will be the southward sagging cold front with a cooler/more stable postfrontal air mass - convection could turn more elevated while racing to the NE. The hail risk however could extend all the way into W Slovakia.

An nocturnal cluster with elevated convection will continue E/NE and will cross Slovakia into S Poland. Heavy rain and isolated hail will be the main issue. Dependant on the magnitude of MUCAPE, a spotty large hail event can't be ruled out (especially if IFS verifies). This risk however seems too low in the poor man's ensemble to upgrade for now. Moisture advection into S Poland ahead of this wave has to be monitored closely as not much BL modification is needed for a more pronounced severe wind gust/hail threat into S Poland.