Storm Forecast
Valid: Fri 25 Mar 2011 06:00 to Sat 26 Mar 2011 06:00 UTC
Issued: Thu 24 Mar 2011 13:24
Forecaster: TUSCHY

SYNOPSIS and DISCUSSION

The extensive high pressure area over Europe weakens with unsettled conditions expected over the Iberian Peninsula and NE-Europe.

Spain and Portugal:

Better LL moisture beneath northward moving EML results in modest MLCAPE over that area. Shear is weak, so expect scattered initiation (diurnal cycle) with slow moving thunderstorms. Locally heavy rain and gusty winds are expected. However, despite weak shear and therefore limited updraft organization, mid-levels are cold with modest mid-level lapse rates forecast. Hence any stronger updraft may produce an isolated large hail event. Overall synoptic conditions remain marginal at best so no level area will be added.

Estonia/Latvia east/southeastwards 9-15 Z:

Boundary layer air mass features scarce moisture as very cold mid-level air overspreads the forecast area from the NW. Forecast model data indicates a broad swath with low-end CAPE, so widespread showers/isolated thunderstorms are forecast. Shear is very strong at mid-/upper levels, but weak updrafts may fail to benefit from this kinematic environment. Marginal hail/strong wind gusts will be the main hazard, although an isolated tornado can't be ruled out, given low LCL and locally up to 200 m^2/s^2 SRH1. Threat decreases around sunset.

Extreme E-France:

Daytime and orographically driven convection results in somewhat augmented chances for an isolated and short lived thunderstorm mainly during the late afternoon hours.