Weerwoord | Estofex: Morgen Oosten Code 1, rest kleine onweerkans

Storm Forecast
Valid: Sun 01 Jul 2007 06:00 to Mon 02 Jul 2007 06:00 UTC
Issued: Sat 30 Jun 2007 15:38
Forecaster: DAHL

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... southern France ... Alpine Region ... Germany

Current model guidance suggsts that the warm sector air over France and Germany will be covered with high and - partly precipitating - mid-level clouds, which will limit the degree of destabilization ahead of the cold front. Current thinking is that weak CAPE will still develop locally, especially where cloudiness has been thin enough to allow for some solar heating at the surface. Deep shear will likely be on the order of 20 m/s which will be supportive of organized multicells and mesocyconic storms. However, chances exist that storms will be largely imbedded in stratiform precipitation and maybe fail to become surface-based. However, confidence in at least isolated surface-based evolution along and ahead of the cold front is sufficiently high to warrant a level-one threat. Main risks will likely be marginally severe hail/wind and maybe aso a brief tornadfo or two gven 10 m/s LLS in over portions of the warm sector.

Somewhat less disturbed pre-convective environment may develop further NW over Germany, where GFS' CAPE signals are somewhat stronger. Storms should initiate along the SFC cold front as well as ahead of it along an airstream boundary expected to stretch across the warm sector. Additional topographically-forced storms are possible as well. Deep shear will be on the order of 15 m/s which may be supportive of some organized multicellular storms capable of marginally severe hail/wind. Isolated/brief mesocyclonic storms cannot be excluded, which would augment the hail threat. Best DLS ist current thought to exist over northern parts of Germany. LLS seems to be maximized over central portions of Germany in the evening hours, but likely over regions where CAPE and DLS will be minimized. So it seems that allover severe threat is somewhat marginal.

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