Storm Forecast
Valid: Wed 05 Jun 2019 06:00 to Thu 06 Jun 2019 06:00 UTC
Issued: Tue 04 Jun 2019 22:02
Forecaster: PUCIK

A level 2 was issued across W Germany, E Holland, E Belgium mainly for excessive rainfall, severe wind gusts and large hail.

A level 1 was issued for NE Spain mainly for large hail.

A level 1 was issued across NW Switzerland, N Italy and Slovenia mainly for excessive rainfall and large hail.

A level 1 was issued across parts of Balkans and Central Europe mainly for excessive rainfall and large hail.

A level 1 was issued across Ukraine and Caucasus mainly for excessive rainfall and large hail.

A level 1 was issued across Turkey mainly for large hail and severe wind gusts.

DISCUSSION

For details on the synoptic-scale pattern and large scale environment, refer to the extended outlook: http://www.estofex.org/cgi-bin/polygon/showforecast.cgi?text=yes&fcstfile=2019060606_201906040233_2_extendedforecast.xml


** Forecast text refers only to the changes compared to the extended outlook **

... E France towards BENELUX and W Germany ...

No significant changes were made for this area. That said, uncertainty still exists regarding the surface based convection over W Germany. Models simulate strong precipitation signals in the wake of the cold front, in the zone of the elevated CAPE. With southerly mid-tropospheric flow concentrating cells along an eastward-moving cold front, a training pattern may potentially evolve over western parts of Lvl 2 and Lvl 1. Thus, heavy rainfall was added as a threat in this forecast.

To the north of the advancing surface low, easterly flow veering and increasing with height will contribute to more than 15 m/s of 0-3 km bulk shear and locally over 200 m2/s2 of SRH in the 0-3 km layer. There is a narrow belt, where such strongly sheared conditions overlap with surface based instability. While the initiation in this area is questionable, any storm forming here would be capable of severe wind gusts or large hail.

... NE France ...

A marginal Level 1 for large hail was added for this region as strong DLS overlaps with marginal CAPE. Stronger cells may produce hailstones exceeding 2 cm in diameter.

... Balkans and parts of Central Europe ...

Level 1 was expanded as forecast soundings suggest high RH throughout the troposphere, low LCLs and slow storm motions, exacerbating the heavy rainfall risk. Stronger cells may also be capable of large hail.