Mesoscale Discussion
Valid: Thu 07 Jul 2022 11:00 to Thu 07 Jul 2022 14:00 UTC
Issued: Thu 07 Jul 2022 11:02
Forecaster: TUSCHY

This MESOSCALE DISCUSSION was issued to highlight a gradually increasing risk of strong to severe convection between 11Z-20Z.

Latest dewpoint readings offer mid/upper tens over NE Italy with lower twenties next to the Adriatic Sea but a drop into the lower tens over Slovenia due to diurnal mixing from drier air up to 800 hPa AGL.

Mountain convection along the Alps is forecast to flare up around noon which is already recognizable in latest radar data from S Austria and a rapid increase occurs during the afternoon with the approaching synotpic-scale front from the NW (partially occluded cold front).

Over Slovenia into Croatia the anticipation of a level 2 event in the SWODY-2 time frame lowered in tandem with lower BL moisture/CAPE. Nevertheless, 400-800 J/kg, locally up to 1500 J/kg MUCAPE with 10-15 m/s DLS and rather steep LL lapse rate assist in the development of a progressive strong/partially severe MCS event, which crosses Slovenia from NW to SE before weakening further S/SE. Hail and wind will be the main issue.

The severe risk inreases towards NE Italy as we approach the belt of the anomalous intense mid/upper jet. DLS rises to 15-30 m/s from E to W with up to 15 m/s in the lowest 3 km. As thunderstorms move off the mountains into a 1000-2000 J/kg MLCAPE environment with the aforementioned shear space, expect multicells and a few supercells to move S with large to very large hail, severe wind gusts and heavy rain.
A conditional tornado risk evolves during the late afternoon onwards as this activity approaches the Adriatic Sea, where LCLs lower somewhat (next to the diurnal decrease). During the evening onwards, this activity tends to transform into a progressive MCS within the SW part of the MD area, which will be covered in a separate MD.