Improved Detection Using Negative Elevation Angles for Mountaintop Radar KMSX Near Missoula, Montana

KMSX, near Missoula, Montana, is one of the U. S. National Weather Service's WSR-88 radars that are located on the top of a mountain. Since all WSR-88Ds employ scanning strategies that were developed for flatland radars, mountaintop radars send signals up into space instead of down over the populated valleys and terrain surrounding the radars. Forecasters who use mountaintop WSR-88Ds are at a distinct disadvantage in not being able to detect crucial weather phenomena within the lowest several kilometers above the surrounding terrain. The use of negative elevation angles has been proposed as a solution to this problem. The feasibility of KMSX using negative elevation angles is simulated using several different weather situations. The simulations show a potential for improved detections of low-altitude weather conditions in the valleys and improved estimates of precipitation amounts over the surrounding complex terrain.