Severe wind induced by orographic effects during cold airmass advection over Carpathian Mountains

Advection of the cold arctic airmass represents a major cause of severe wind cases in East Slovakia. It is caused by cold and dry airmass separated by orographic barrier, descending, and rapidly flowing on its leeward side. Local open and narrowing topography of the East Slovakia further increase the windspeed in Kosice basin and Zemplin area. Different characteristics of the windspeed and wind gusts were observed when categorizing the situations for cold maritime and continental origin of the airmass. The most representative case studies for each category were analysed using numerical weather prediction model, field observations and reported wind damage. Maritime airmass tends to be defined in deeper vertical profile and its advection is often accompanied by stronger wind gusts, of which some may also by partly convective considering the unstable vertical profile in the later stage of the advection within the cold sector of the low. The continental airmass is shallower and topped by strong stable layer and tends to produce higher sustained wind speed during the advection. Considering the right height of the stable layer in relation to the orographic barrier a downslope catabatic winds were observed on the leeward side of the orography.