In October 2000, the US Department of Energy, along with NOAA and several other labs and universities, conducted the Vertical Transport and Mixing Experiment (VTMX) and URBAN2000 field programs in Salt Lake City, Utah. The VTMX program focused on the basin-scale flow regime, where the URBAN2000 component focused on transport and dispersion in the downtown Salt Lake City area. In this paper, we will focus on a specific Intensive Operations Period, IOP-10, which occurred on October 25-26, 2000.

IOP-10 was chosen because the winds in the downtown area were fairly weak and variable early in the experiment, and became more windy in the later part of the IOP. We will present a large-eddy simulation of the downtown Salt Lake City area, simulating the first SF6 release that occurred during IOP-10, during the night of October 25-26, 2000. The LES code was initialized using observed conditions from profiler, sodar, and rawinsonde data, which were averaged over the time period of the first release. A comparison of the model produced wind fields, turbulence, and dispersion will be made to the observations. The sensitivity of the simulation to the model initialization will be discussed.