Storm Forecast
Valid: Fri 01 Jul 2016 06:00 to Sat 02 Jul 2016 06:00 UTC
Issued: Thu 30 Jun 2016 19:43
Forecaster: TUSCHY

A level 1 was issued for the Baltic States and NE-Poland mainly for an isolated large hail and tornado event and locally excessive rain.

A level 1 was issued for the CNTRL/E-Ukraine and the Black Sea mainly for isolated large hail and excessive rain.

A level 1 was issued for N-Italy and parts of Austria/Slovenia mainly for excessive rain.

A level 1 was issued for N-Morocco mainly for an isolated large hail event.

SYNOPSIS

A strong cyclonic vortex is placed over far NW Europe. A trough circles its base from Ireland to the North Sea during the forecast. Else, only minor upper-level waves/(thermal) troughs add a risk for thunderstorms to numerous regions.

DISCUSSION

Enhanced DLS remains displaced from most decent instability during the forecast. Still a few places see adequate conditions for a few organized storms:

The Baltic States see 500-1000 J/kg MLCAPE and 10-15 m/s DLS, increasing from east to west. A few organized multicells with large hail and strong to isolated severe wind gusts may occur. Clustering and slow storm motions also tend to enhance the flash flood risk. In addition, 150 J/kg LLCAPE is forecast, which should induce a low-end tornado risk for that region. The risk diminishes during the night.

CNTRL/E-Ukraine and the Black Sea will see strong MLCAPE build-up of 1-1.5 kJ/kg. Very weak deep layer flow and rich BL moisture indicate an augmented risk for flash flood producing thunderstorms. Weak BL convergence should keep thunderstorm coverage below a level 2 threshold. Isolated large hail is possible as storms mature. Thunderstorms weaken during the night.

N-Morocco experiences 15 m/s DLS with 400-800 J/kg MLCAPE. An isolated large hail event is possible.

N-Italy to Slovenia and S-Austria will see decent BL moisture with weakly capped 500-1000 J/kg MLCAPE. Weak DLS precludes organized DMC, but clustering storms may pose an excessive rainfall and isolated large hail risk. This activity gradually weakens during the night.

UK may see a few funnel events with pulsating storms during the afternoon/evening. Cold mid-troposphere may support a few marginal/isolated large hail events with strongest thunderstorms. No level 1 was issued for that risk.

15-20 m/s DLS overlaps with marginal CAPE over NE Germany, but degree of MLCAPE (less than 300 J/kg) should lessen the risk for organized DMC. In case of an isolated stronger updraft due to better BL moisture content, strong wind gusts and marginal hail would be the main hazard.

Spotty thunderstorms along the mountains may bring isolated large hail over E-Spain but coverage remains too marginal for a level 1.