Original scientific paper

OBJECTIVE FORECASTING OF FOEHN FOR THE SUBGRID SCALE WIPP VALLEY

S. Drechsel ; Institute of Atmospheric Physics, DLR Oberpfaffenhofen, Germany
G.J. Mayr ; Department of Meteorology and Geophysics, University of Innsbruck, Austria

Abstract

This study provides a method for an objective, probabilistic forecast of foehn based on the operational global model of the European Centre for Medium-Range Weather Forecast (ECMWF). Foehn strongly depends on topographical features, which are not yet resolved in operational global models. Therefore the proxi-parameters vertical difference of potential temperature Δθ, cross-barrier pressure difference Δp, and downstream wind v, derived from the well investigated foehn dynamics are studied for their suitability as foehn predictors. Testing them for the subgrid scale Wipp Valley, Δθ and Δp yielded better results than v. Further improvement could be achieved by combining Δθ and Δp to joint predictors, with a strongly increasing foehn probability for increasing Δp and decreasing Δθ.

Keywords

foehn; forecasting; MAP

Hrčak ID:

64419

URI

https://hrcak.srce.hr/64419

Publication date:

15.12.2005.

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