Storm Forecast

Storm Forecast
Valid: Mon 11 Jan 2016 06:00 to Tue 12 Jan 2016 06:00 UTC
Issued: Mon 11 Jan 2016 00:40
Forecaster: VAN DER VELDE

A level 1 was issued for parts of France and the northern Adriatic Sea region mainly for isolated severe convective wind gusts and tornadoes.
A level 1 was issued for N Ireland mainly for severe convective wind gusts.

SYNOPSIS and DISCUSSION

A large depression is stationary over northern UK with the 1013 hPa isobar connecting Portugal, Ukraine and N Sweden, with steep pressure gradients and strong winds within. A cold front emanates from an occlusion over central UK over Netherlands into W Germany and E France around noon. The cool airmass behind the front is unstable with some 200 J/kg MLCAPE near the English Channel and the west coast of France. The jet stream blows over N Spain, S France and the Alps, creating 20-50 m/s 0-6 km shear and over 20 m/s 0-1 km shear over France where some CAPE is present as well. This increases the chance of severe convective wind gusts as well as isolated tornado chances. The same is the case in the Slovenia region, where GFS predicts over 300 mē/sē of 0-3 km SREH in combination with a modest but plausible CAPE signal at 18Z.
During the night a convective band should train onto the N Ireland coast under very sharp pressure gradients it may cause severe wind gusts (but of course also also non-convective severe gusts)

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