Storm Forecast
Valid: Sat 05 Jun 2010 06:00 to Sun 06 Jun 2010 06:00 UTC
Issued: Sat 05 Jun 2010 00:32
Forecaster: VAN DER VELDE
SYNOPSIS
The weather pattern shows an upper low over the southern Balkan and Turkey filled with an unstable airmass and most dynamics over Turkey, high pressure over central Europe, and a large area of shallow low pressure over the eastern Atlantic. An upper trough approaches western Europe and frontogenesis takes place as low level warm air flows northward and meets cooler air from the ocean. In the warm airmass CAPE develops.
DISCUSSION
...N Spain, SW France...
MLCAPE is not extraordinary, so storms may initially struggle, but 15-20 m/s 0-6 km shear vectors and 0-3 km SREH >100 mē/sē together with LCL heights near 2000m may favor an isolated marginally large hail event (around 2 cm). The probability seems not enough to warrant a level 1.
During the evening, models hint at MCS formation over eastern Bay of Biscay and/or Basque country with CAPE being mostly elevated. In that case the enhanced SREH below the lifted parcel level will not lead to much of a severe weather potential, and mid level winds and CAPE are too weak for a gusts threat.
...W/C Turkey...
Some potential exists for severe convective storms, but the pattern of instability and shear and helicity vs. stratiform precipitation seems rather messy. The main lift from the shortwave trough comes at night when CAPE appears to be mostly elevated. 1-4 km vectors, i.e. above the surface inversion, are large though. It seems to become a rainy event but an embedded storm wth supercellular traits is not ruled out.
But low LCL and CAPE are not great for large hail, and low level shear lacking for tornadoes or gusts.
