Storm Forecast
Valid: Thu 06 Jul 2006 06:00 to Fri 07 Jul 2006 06:00 UTC
Issued: Thu 06 Jul 2006 05:11
Forecaster: GATZEN
SYNOPSIS
A rather weak short-wave trough has entered western Europe and slowly propagates eastward, while high geopotential remains over eastern Europe. Warm airmass characterized by steep low-level to mid-level lapse rates is present in the range of the short-wave trough from British Isles to eastern Germany and further to western Mediterranean. Rich low-level moisture has formed over western Mediterranean. While weak shear profiles are expected over most of Europe, strong vertical wind shear should be present over Mediterranean. Over central Europe ... single cells and clusters should develop during the day. Some isolated hail/wind events are not ruled out, but chance seems to be rather weak.
DISCUSSION
Southern France, northern Italy
Strong upper jet streak travels eastward over western Mediterranean. To the north of this jet streak ... a frontal boundary moves eastward over southern France. Along and east of this front ... WAA is expected over southern France and northern/central Italy ... where QG forcing is likely. Latest numerical models show weak surface low pressure system that should develop over western Mediterranean Sea. To the north and northwest of this low ... tongue of moist boundary-layer airmass expands from Balearic Islands to southern France as indicated by latest soundings. Although this moist airmass is strongly capped over western Mediterranean ... height falls should weaken the cap along the frontal boundary. During the day ... initiation seems to be possible over southern France and northern/central Italy ... especially in the range of outflow-boundaries and sea-breeze convergence lines. Strong DLS of 20-25 m/s is expected ... and multicells and supercells are likely to form ... capable of producing large, isolated very large hail ... and severe wind gusts. The chance for tornadoes seems to be relatively low ... given weak low-level instability and vertical wind shear.
