Storm Forecast
Valid: Mon 28 Sep 2009 06:00 to Tue 29 Sep 2009 06:00 UTC
Issued: Sun 27 Sep 2009 21:10
Forecaster: DAHL

A level 2 was issued across eastern Spain and the extreme western Mediterranean Sea mainly for excessive convective precipitation.

A level 1 surrounding the level 2 was issued across eastern Spain and the extreme western Mediterranean Sea mainly for excessive convective precipitation.

A level 1 was issued across the Ionian Sea mainly for excessive convective precipitation.

SYNOPSIS

Quite intense upper frontal zone is stretching across the N Atlantic and the N parts of Europe. An imbedded trough will move from the Norwegian Sea into the Baltic states during the period, while undergoing considerable amplification. A rather extensive SFC low over N Europe is attendant to this feature, resulting in a southward surge of polar air which will reach the southern Baltic Sea and the Baltic States late in the priod. Over the southern parts of Europe, synoptically quiescent comditions persist.

DISCUSSION

... E Spain ... extreme W Mediterranean Sea ...

Main focus for severe convective weather will be a rather stationary, small upper low, anchored off the Iberian east coast during the priod. Instability will be rather meager but sustained low-level convergence should maintain one or more training MCSs over E Spain through the period. These storms will
pose a threat for excessive convective precip. Storms along the coast and over the sea will have the potential for producing non-supercellular tornadoes given strong low-level buoyancy.

... SW Medietrranean Sea north of Algeria ...

Farther southwest, deep shear is simulated to increase to about 20 m/s. However, it does not seem that many storms will develop in this environment, so the severe threat should be rather low. If storms form, an isolated severe wind gust/hail event or two cannot be ruled out. Probabilites for severe weather are too low for a LVL 1 threat.

... Ionian Sea ...

Over the Ionian Sea, there will be another regime with ample moisture and slow storm motion and accordingly high accumulated precip amounts. In addition, waterspouts may occur. The threat will last throughout the period.