Doppler Lidar Observations of a Downslope Windstorm

Abstract

During January and February 1987, the NOAA/WPL pulsed Doppler lidar was deployed in the foothills west of Boulder, Colorado, to study orographically induced flows over the Continental Divide. On 29 January 1987, the lidar, with its unique spatial and temporal data-gathering capabilities, documented a downslope windstorm affecting the Boulder area and the rest of the Front Range. The lidar recorded in detail 1) a low-level leeside wind maximum, 2) propagating wind gusts exhibiting two distinct periodicities, and 3) the eastern edge of a mountain wave feature where a jumplike flow reversal occurred. Such structures have not previously been observed with comparable detail by conventional in situ and remote sensing instruments. The observed phenomena were similar to results obtained from mountain-wave numerical models. The most notable of the structural similarities was between the observed and modeled wind gusts.