A special field program was carried out to investigate mesoscale structure of the lower atmosphere in a desert region with complex terrain. Measurements from an array of three 924-MHz lower atmospheric profilers were collected over a two-month period of study in June and July 2000. Horizontal winds derived from the profilers and automated surface measurement were quality controlled and used in kinematic analyses. Divergence and vertical motions were calculated for day and night flow regimes. The results were used in validation studies with the Penn State/NCAR Mesoscale Model Version 5 to investigate mesoscale predictability.