Use of Radar Observations in Hydrology and NWP models

Weather radars have provided a focus for three previous COST Actions over the last twenty years or so namely COST 72, 73 and 75. During this period the deployment of operational radars increased rapidly from one in 1970 to over 120 currently, quickly approaching 150 in the near future. Figure 1 shows the approximate state of the current European inventory of operational weather radar as compiled by the EUMETNET \footnote{European Meteorological Network} programme OPERA \footnote{Operational Programme for the Exchange of Weather Radar Information}. The recently completed COST 717 Action `Use of Radar Observations in Hydrological and NWP models' is the fourth effort in this series and ran from 1999 to 2004. The present document constitutes the Final Report of COST 717.