CONVECTIVE FORECAST
VALID 06Z MON 01/09 - 06Z TUE 02/09 2003
ISSUED: 31/08 17:19Z
FORECASTER: DAHL

General thunderstorms are forecast across SW ... central and E Europe.

SYNOPSIS

Only brief discussion today ... Thermodynamic profiles have weakened substantially across SRN Europe as mid-level steep-lapse rates associated with the EML are no longer present. NRN parts of the forecast area will be affected by more or less deep convectively mixed polar air ... with minimal CAPEs. Soundings across the W and central Mediterranean show MLCAPEs in excess of 1000 J/kg ... with a decrease in PBL-moisture depth towards the south. Weakly unstable inverted-V type profiles are present over the S Balkans.

DISCUSSION

...E/SE Europe...
Low level flow across the Balkans will lose its upslope component per numerical model guidance ... also ... QG omega will likely be positive owing to low-level CAA and no appreciable differential vorticity advection. Over Greece though ... primarily orographic forcing for low-level UVM will be likely present ... but in the absence of strong mid/upper cooling ... CAPE should remain negative ... and TSTMS are rather ulikely. If low-level moisture was sufficient locally to support some CAPE ... dry environment and strong mid-level flow would promote strong/severe wind gusts if storms formed. However ... confidence in TSTM development is quite low ATTM.

Farther E/NE ... along/ahead of the cold front over E Europe/Black Sea associated with short-wave trough at the periphery of the main European upper trough ... a few TSTMS will likely develop during the day. CAPE is expected to be rather weak ... possibly below 1000 J/kg ... but rather dry BL along with ample deep-layer shear should support strong TSTM outflow winds and possibly some hail ... briefly exceeding severe levels.

...Iberia...
TSTMS could also develop over Iberia ahead of vort max again ... combination of dry low/mid-levels and 50+ kts deep-layer shear will maintain slight severe straight-line wind threat.

...Central Europe...
Shallow TSTMS will likely continue across wide portions of central Europe ... though an isolated hail/wind event or two may occur given moderately strong shear ... organized severe TSTM threat remains low.

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