Surface layer observations from a network of 22 automatic weather stations covering the northern COPS region, with case study of MCS passage on 20th July 2007

During July & August 2007, the University of Leeds installed a network of 12 Automatic Weather Stations (AWS) in the Northern part of the COPS region as part of a larger network that included a further 10, deployed by the University of Innsbruck. Sites were chosen to provide surface observations in four categories relating to the region's orography. These were; Inflow valleys, Mountain Ridges, Convection Hotspot & Westerly Upslope Flow. Here, an overview of the quality & availability of both data sets is presented, with a greater focus on that collected by the Leeds stations.

Observations recorded by the Leeds AWS's included analogue temperature at 2 heights, digital temperature & humidity, 2-Dimensional windspeed & direction, and pressure. Precipitation rates were also measured at 6 of the Leeds sites as part of the Innsbruck deployment.

A case study is presented, showing passage of a Mesoscale Convective System (MCS) on 20th July (IOP 9c). Very interesting flow features were captured, with wind data showing the apparent decoupling of N-S aligned valley flow, from those aloft. One suggested interpretation is that the steep gradient of the Murg Valley has in this case effected a sheltering influence on the synoptic-scale Westerly flow.