Storm Forecast
Valid: Thu 19 Dec 2013 06:00 to Fri 20 Dec 2013 06:00 UTC
Issued: Wed 18 Dec 2013 21:11
Forecaster: GATZEN

SYNOPSIS

A mid-level ridge has developed over southern and eastern Europe in the wake of a cut-off low that weakens over southern Turkey. Given dry low-level air masses, potential of deep moist convection is limited except for the east Mediterranean Sea. Better moisture is located across western Europe ahead of an Atlantic trough that moves eastward on Thursday morning. The southern part of this trough will start to cut-off over the Iberian Peninsula, whereas the northern portions will travel across the North Sea.

Low moisture across the continent will limit the chance of any convection. Best potential is expected over the south-western Iberian Peninsula, where moist air masses from the Atlantic will be advected ahead of the cold front. The overlap of this moisture with increasing lapse rates and strong 0-1 km low-level vertical wind shear of 12 m/s onshore will be supportive for mesocyclones embedded in the cold frontal rain band. Therefore, a few tornadoes are not ruled out, but the overall chance seems to be too marginal for a risk level.

In the wake of the cold front, rather dry air masses are advected eastward. Deep moist convection is most likely over the warm sea waters in the range of vorticity maxima that travel north-east. Severe storms are not expected as the vertical wind shear remains rather weak.