Modeling Studies of Urban Heat Island Induced Surface Mesovortices over the Saint Louis Metropolitan Area

Although the high spatial and temporal resolution data from the QuantumWeather surface mesonet shows the presence of the surface mesovortices observed downwind from the urban heat island (UHI), the vertical structure of these mesovortices is not well understood. In order to fully understand the structure of these mesovortices a WRF simulation, assimilating the surface mesonet data, was conducted for two days when mesovortices were observed. The high resolution WRF simulations were able to reproduce the observed surface structure of the vortices in association with UHI. These simulations were then carefully examined to determine the full three-dimensional structure of the vortices. Preliminary results from the WRF simulations suggest that the interaction between the Saint Louis UHI, the Mississippi River modify the wind field creating the surface mesovortices.