Forecast Update
Valid: Fri 07 Mar 2008 13:00 to Sat 08 Mar 2008 06:00 UTC
Issued: Fri 07 Mar 2008 13:42
Forecaster: TUSCHY

SYNOPSIS

Please refer to the outlook issued at Thu 06 Mar 2008 20:59 Z.

DISCUSSION

...E-Greece and S-Bulgaria....

NE-ward lifting upper-level low and attendant forcing overspread the area of interest from the SW during the evening hours. Instability will be the main limiting factor for a more robust thunderstorm threat but anticipated moderate lapse rates at mid-levels and a surge of LL moisture towards Bulgaria should provide enough fuel for isolated-scattered thunderstorm development. Best chance for thunderstorms to become surface based will be confined to the coastal areas where LL moisture is the best.
Prefrontal warm sector should stay capped so main focus for development will be an eastward trailing cold front. Kinematics especially at low levels are great and LL mesocyclones can form as helicity in the lowest 1000 m increases to 200 J/kg. In addition, DLS picks up during the evening hours and thunderstorms could produce wind gusts matching our criterion.
Instability diminishes rapidly well inland and so does the severe weather risk although an isolated large hail report over central / south Bulgaria can't be exlcuded as helicity up to 3km stays strong.