Storm Forecast
Valid: Sat 04 Oct 2008 06:00 to Sun 05 Oct 2008 06:00 UTC
Issued: Fri 03 Oct 2008 22:44
Forecaster: GROENEMEIJER

SYNOPSIS

Saturday at 0600 UTC... a large trough located along an axis from S Scandinavia to Corsica/Sardinia moves eastward while a low gradually cuts off from its base. A strong cyclonically-curved jet streak is forecast to develop at its base, moving eastward across the Ionian Sea into the southern Balkans.
Another intesne mid/upper-level low associated about 500 km north of Scotland moves southeastward and S Norway on Tuesday morning. This system is associated with a deepening surface low over the northern north Sea.

DISCUSSION

...Albania, western Greece, Ionean Sea...

As the aformentioned strong jet streak and trough move eatsward, intense forcing for upward vertical motion are expected. During the afternoon and evening, a cold fron is expected to surge eastward across the Ionean Sea reching Albania and western Greece during the late evening. Widespread convection is expected along the Adriatic and Ionean coasts during the evening and later further inland as wlel. With 0-3 km bulk shear on the order of 15-20 m/s and about 1000 J/kg MLCAPE available, chances of severe weather marginally warrant a level 2. We expect mostly clustered activity along the front, whereas more isolated storms, including supercells, occur ahead of it. Severe weather will likely include some large hail and damaging winds.

...N and NE Greece, F.Y.R. of Macedonia, Bulgaria...

Convection, likely linearly organized alogn the cold front should move inland into Gree late Staurday evening and overnight. A damaging wind threat will likely persist. A 15 m/s low-level (0-1 km bulk) shear developing ahead of the cold front as a low-level jet develops, should also create some threat of weak tornadoes mainly across northern greece and S Bulgaria. Elsewhere, some damaging gusts, hail and flash floods are the main severe threats.

...North Sea, Netherlands, W Denmark, extreme S Norway...

As a low pressure system develops Saturday afternoon near the Shetland Islands, frontogenesis is expected across much of Britain. A cold front preceded by an intense 30-35 m/s low-level jet is expected to pass the indicated level 1 area. 500-800 m2/s2 SRH-3 and up to 25 m/s 0-1 km shear are expected to form within the prefrontalair-mass, and the front will likely feature linear convective elements. Severe convectively-enhanced gusts are possible. A few isolated tornado events are not ruled out upon the front's passage.