Storm Forecast
Valid: Thu 16 Jul 2020 06:00 to Fri 17 Jul 2020 06:00 UTC
Issued: Wed 15 Jul 2020 22:23
Forecaster: GATZEN

A level 1 was issued across northern Tunisia for large hail and severe wind gusts.

SYNOPSIS

Broad low geopotential is present across Europe downstream of west-European ridging. Two almost barotropic mid-level vortices are embedded in the large trough, one over east Germany and west Poland, one across north-west Russia. A weak short-wave trough travels across the southern Balkans. At low levels, ffrontal boundaries are present across northern Africa and northern Turkey. A wweak frontal boundary also extends over the Alps into Poland. Weak mid-level flow over most places will limit vertical wind shear. Additionally, weak lapse rated and limited low-level moisture result in low CAPE below 1000 J/kg. Storms that form will be mostly disorganized and not associated with severe weather.

Some large hail and severe wind gusts are expected from east Poland into Belarus and the west Ukraine where CAPE is locally close to 1000 J/kg and low-level mixing results in higher DCAPE. Some waterspouts and non-mesocyclonic tornadoes are forecast across northern Poland where rich low-level moisture and quite high SBCAPE are present in a weakly sheared environment close to the mid-level trough center.

Another area with slightly higher CAPE and a potential for large hail and severe wind gusts is the Caucasus region and southern Italy, where also a severe rain threat exists.

DISCUSSION

Northern Tunisia

Some isolated storms are expected after peak heating over the montains. MLCAPE is as high as 1500 J/kg due to some moisture advected inland overlapping with steep lapse rates. About 15 m/s deep layer shear support some multicells that are forecast to be capable of large hail and severe wind gusts.