Storm Forecast
Valid: Thu 15 Feb 2018 06:00 to Fri 16 Feb 2018 06:00 UTC
Issued: Wed 14 Feb 2018 23:56
Forecaster: GATZEN

SYNOPSIS/DISCUSSION

A deep trough cuts off across the east Mediterranean and slowly digs south. At its eastern flank, a moist air mass becomes slightly unstable during the period as the trough and associated steep lapse rates spread east. Some embedded thunderstorms are expected late in the forecast period. Given strong vertical wind shear, well developed multicells are forecast, even though CAPE is weak. Locally large hail and a tornado or two are not ruled out. Further west, showers and thunderstorms in the weakly-sheared trough center are not expected to become severe, except for a weak waterspout risk close to the shores.

Over south-western Europe, a moist maritime air mass with weak CAPE advects towards the Iberian Peninsula. Weak large-scale forcing at the anticyclonically sheared flank of an Atlantic jet is indicated by latest models. A stratiform rain band along the cold front may produce some local thunder but organized storms are not expected.

Over north-western Europe, intense polar trough with steep lapse rates will move slowly east. Showers and thunderstorms are possible over the rather warm sea surface although low-level moisture is limited. Ahead of the trough, some thunderstorms may form along the cold front that approaches western Norway. However, latest model guidance does not indicate substantial CAPE and current thinking is that only embedded storms will form. Severe wind gusts and a tornado or two are not ruled out given the strong vertical wind shear.