CLOUD MODEL SIMULATIONS OF SURFACE WEATHER ELEMENTS ASSOCIATED WITH WARM FRONTAL REGIONS OF WINTER STORMS

Cold season warm-frontal systems are simulated with a 2-D cloud-resolv ing model, The organization of surface weather elements (precipitation type and intensity, factors affecting visibility, accretion, blowing snow and surface wind) in the vicinity of the surface front an investi gated. The patterns of surface weather conditions in the model storms are in good agreement with those observed in real systems. The organiz ation of weather elements is found to be sensitive to large-scale cond itions such as background stability, temperature and frontal forcing. These surface weather conditions are also found to be affected signifi cantly by cloud-scale and mesoscale dynamical processes. The implicati ons of the model results to the improvement of quantitative forecastin g of weather elements in winter storms are discussed. (C) 1997 Elsevie r Science B.V.