USE OF MULTIMODEL SUPERENSEMBLE TECHNIQUE FOR MOUNTAIN-AREA WEATHER FORECAST IN THE OLYMPIC AREA OF TORINO 2006

The XX Olympic Winter Games will be held in Torino, Italy, on February 10-26, 2006 and the IX Paralympic Winter Games on March 10-19, 2006. The Olympic mountain venues are set in middle-, high- and very high-mountain places in the Susa and Chisone Valleys in Piedmont (up to 2600 m above sea level), therefore weather forecasts are strongly dependent on the complex geography and orography of these valleys. Direct model outputs, even from high-resolution limited area models, show many strong systematic and random errors in the forecast, compared to the values observed by our high-density non-GTS network. We present some results of the Multimodel SuperEnsemble technique (Krishnamurti et al. 2000) applied on both global circulation models and on nonhydrostatic limited-area models. The Multimodel SuperEnsemble technique takes into account various model outputs, weighted by parameters calculated in a training period. This is one of the first applications of this technique with limited-area models and in a narrow mountain area and results show a good improvement of meteorological parameter forecasts such as temperature and precipitation

USE OF MULTIMODEL SUPERENSEMBLE TECHNIQUE FOR MOUNTAIN-AREA WEATHER FORECAST IN THE OLYMPIC AREA OF TORINO 2006

The XX Olympic Winter Games will be held in Torino, Italy, on February 10-26, 2006 and the IX Paralympic Winter Games on March 10-19, 2006. The Olympic mountain venues are set in middle-, high- and very high-mountain places in the Susa and Chisone Valleys in Piedmont (up to 2600 m above sea level), therefore weather forecasts are strongly dependent on the complex geography and orography of these valleys. Direct model outputs, even from high-resolution limited area models, show many strong systematic and random errors in the forecast, compared to the values observed by our high-density non-GTS network. We present some results of the Multimodel SuperEnsemble technique (Krishnamurti et al. 2000) applied on both global circulation models and on nonhydrostatic limited-area models. The Multimodel SuperEnsemble technique takes into account various model outputs, weighted by parameters calculated in a training period. This is one of the first applications of this technique with limited-area models and in a narrow mountain area and results show a good improvement of meteorological parameter forecasts such as temperature and precipitation