The weather radar system of north-western Italy: an advanced tool for meteorological surveillance

North-Western Italy is a geographical region characterized by complex orography with many river catchments. Severe meteorological conditions frequently leads to flood situations due to very high rainfall amounts. In addition to a quite dense net of rain gauges, in the last three years two Doppler radar systems have been installed to provide a continuous monitoring of the region. The Bric della Croce radar, with a magnetron transmitter, was installed in 1999 above the Turin hill, at 736 m height, and is now fully operational with real-time data transmission to the regional weather service in Turin via a radio link. It has been recently updated to dual polarization. The second radar was installed at the end of 2001 on the top of the Settepani mountain, at about 1400 m height in the Ligurian Apennines. It is a klystron equipped system, with dual polarization capabilities and a full digital receiver. The radar sends real-time data to the regional weather service via a satellite link. In this paper a general description of both radar systems is given, with a special emphasis on the issues related to the surrounding mountainous environment. Due to a distance of about 90 km between the two radar sites, combining their measurements offers a chance to face problems due to beam blocking and allows to derive a detailed wind field over a wide area, in one of the most meteorologically interesting regions in Europe.