Storm Forecast
Valid: Thu 30 Jun 2022 06:00 to Fri 01 Jul 2022 06:00 UTC
Issued: Wed 29 Jun 2022 22:43
Forecaster: GATZEN

A level 2 was issued across north-western Poland and western Baltic States for heavy rain and to a lesser extent tornadoes and severe wind gusts.

A level 2 was issued across western Alps and south-western Germany for heavy rain and to a lesser extent large hail and severe wind gusts.

A level 1 was issued across western Germany, Benelux, eastern France, north-western Italy far heavy rain, severe wind gusts, and large hail.

A level level 1 was issued for Poland and Baltic States for heavy rain, severe wind gusts, and tornadoes.

A level 1 was issued across northern Sweden for heavy rain.

A level 1 was issued across wester Balkans for heavy rain.

A level 1 was issued across southern Ukraine and Moldova for heavy rain.

A level 1 was issued across western Turkey and Caucasus for heavy rain.

SYNOPSIS

The west European trough is placed across the British Isles. With a south-westerly flow, mid-level vortices lift across western and central Europe. Associated with an intense short-wave trough, a cold front crosses France and enters Germany during the day. Farther east, subtle mid-level flow prevails with a low-level moist air mass.

DISCUSSION

Western Germany, Benelux, eastern France, western Alps, north-western Italy

Ahead of the approaching cold front, a warm and moist air mass is advected north. Widespread initiation is expected along the front, with most activity expected over the western Alps and south-western Germany, where CAPE is highest. Vertical wind shear is sufficient for well-developed multicells, that move along the cold front and are expected to cluster and form a squall line. Supercells are also not ruled out along the level 2 area due to an increasing mid-level jet that ejects from the upstream trough axis.

Heavy rain will be the main threat across the western Alps and south-western Germany, but also severe wind gusts and locally large hail are forecast. Potential is limited farther north due to weaker CAPE and also partly cool boundary layer. Elevated storms can go over the North Sea late in the period thanks to ongoing warm air advection ahead of the cold front.

Western Poland to Baltic States

A weak mid-level vortex moves over the region. It is accompagnied by a strong low-level jet that intensifies in the evening and night. A moist and weakly capped air mass is advected north towards the Baltic Sea, where the sea breece convergence and strong warm air advection indicate the potential of widespread initiation. Backbuilding in a moist air mass with rather low LCL heights highlights a heavy rain threat.

In the evening, low-level shear increases to more than 10 m/s, and the tornado potential increases.

Additional storms will form farther south within the axis of warm air advection. With backbuilding towards the south, heavy rain is also expected. Additionally, some severe wind gusts are possible to the east where deeper boundary layer exists.

Further level 1 areas

In weakly sheared, moist environments, scattered to widespread storms are forecast to preoduce local flash floods. Large hail and severe gusts are not ruled out.