Mesoscale analysis and WRF model verification of a low-level jet, bay breeze, and undular bore at the Howard University Beltsville Research Site

The geography of the mid-Atlantic states lends to the development of low-level jets and sea breezes from the Atlantic Ocean and Chesapeake Bay during the summer. The Howard University Beltsville Research Site in Beltsville, MD, and sites in the surrounding region are well-equipped to capture evidence of these mesoscale phenomenon with the use of a Raman lidar, micro-pulse lidars, a wind profiler, ceilometer, instrumented tower, a National Weather Service WSR-88D Doppler radar, and six Automated Surface Observing System (ASOS) stations within a 50 km radius of Beltsville. Between 3 and 5 August 2007, a low-level jet, bay breeze, and undular bore proceeded a cold front passage over the region and an analysis of these events is conducted using data from the mentioned instrumentation.

The Weather Research and Forecasting (WRF) model was run for these events and is compared to the analysis to assess the degree to which these mesoscale phenomenon are captured given that they are primarily boundary layer features. This analysis will demonstrate the utility of a lidar network for model verification of boundary layer events and highlight the fact that such a lidar network already exists and benefits of it can be achieved by archiving the ceilometer data at ASOS stations. Currently, this data is discarded after the calculation of cloud base heights, but if saved, it has the potential to aide in model verification and provide high-resolution data of boundary layer aerosol concentrations.