Storm Forecast
Valid: Sat 07 Dec 2013 06:00 to Sun 08 Dec 2013 06:00 UTC
Issued: Fri 06 Dec 2013 22:15
Forecaster: PISTOTNIK

No threat levels were issued.

SYNOPSIS and DISCUSSION

Between a mature cyclone and a deep upper-level trough over Western Russia and high pressure over Southwestern Europe, a strong Northwesterly flow covers most of the continent. The jet axis runs from the North Sea via East-Central Europe to Bulgaria and Turkey. It coincides with a sharp but largely inactive frontal boundary which separates cold and dry polar air to the Northeast from moderately mild air to the Southwest and slowly turns warm-active again.
On its cold side, scattered "lake effect" shower activity will affect Poland, the Russian exclave of Kaliningrad, Lithuania and Latvia. It will likely stay too shallow for lightning, but may organize into multicells as soon as it moves onshore, where it encounters frictional convergence and an environment of >15 m/s shear and >200 m^2/s^2 storm-relative helicity, most of it concentrated in the lowest 1 km. An isolated severe wind gust or a brief tornado are not ruled out. However, due to the further slackening wind field this threat seems to be too low for a level 1.
With cold air overspreading the Black Sea, unorganized convection under weak shear may grow deep enough to produce a little lightning, but severe weather is not expected.