Storm Forecast
Valid: Sat 15 Jul 2006 06:00 to Sun 16 Jul 2006 06:00 UTC
Issued: Fri 14 Jul 2006 20:41
Forecaster: TUSCHY

SYNOPSIS

Intense high pressure area over the North Sea continues to affect most parts of Europe.
Main feature of interest will be a SE-ward amplifying trough, which will start to cut-off during the forecast period somewhere southeast of Poland.
A cool and more stable airmass is forecast to be advected southward between those synoptic features.
Again...most areas of the western Mediterranean and surrounding areas will see diurnal driven TSTM activity....The same for parts of western Russia.

DISCUSSION

...SE Europe...

Yesterday's event was blasted because the main shear belt remained well behind the best instability area and therefore in the cool and stable postfrontal airmass.
The same scenario should continue for Bosnia and Herzegovina, Serbia and Romania today.
A well mixed and pretty dry boundary layer should limit the instability release ( ~500-900 J/kg).
Southward shifting, pretty loose developed, cold front will again be the focus for isolated-scattered TSTM development, but an increasingly negative placement in the right exit region of an upper-level jet should limit the coverage.
Lapse rates will still be fine enough for an isolated large hail threat.

...Belarus and parts of western Ukraine...

Developing upper-level cut-off low will slide southeastward very slowly... Right now, there are no signs for a developing low-level depression area, but models like GFS show a nose of lower pressure in the surface pressure field, accompanied by the advection of a marginal warmer and more humid airmass towards the west.
Low - level shear and SRH values are very impressive along the retreating baroclinic zone, but instability / best shear are well separated.
GFS develops convective signals well to the west of the boundary ( with very slim signals of an unstable atmosphere ) in the middle of the best low-level shear , but confidence of this scenario is too low at the moment for issuing higher probabilities.