Using the WSR-88D to Forecast Downburst Winds at Cape Canaveral Air Station and the Kennedy Space Center (CCAS/KSC)

摘要

The 45 Weather Squadron is tasked with providing several convective wind warnings in support of the U. S. Space Program. The forecasters use a radar-based forecast technique to determine if a thunderstorm has the potential to produce a gust that meets warning criteria. This technique, the Echo Top/ Vertically Integrated Liquid Wind Gust Potential (ET/VIL WGP), has not previously been evaluated for use in the Cape Canaveral Air Station and Kennedy Space Center (CCAS/KSC) locale. Additionally, there are two other radar-based forecast techniques that required evaluation for possible inclusion into the 45 WS forecast process. These are the Maximum Reflectivityl Height of Maximum Reflectivity (d/H) Wind Gust Potential and the Storm Top/Vertically Integrated Liquid (STIVIL) Wind Gust Potential techniques. Radar data from 15 pulse-type storms that occurred in the CCAS/KSC locale were collected. Potential wind gust forecasts were calculated using the techniques mentioned above. The forecast and observed wind gusts were analyzed using visual and numerical tools to assess the performance of the WGP techniques. Results of the research indicated that the WGP techniques could not consistently predict the magnitude of the downburst gust. The average errors of the prediction were on the order of 10 knots and were quite variable. Because of the small sample size, these results can not be considered as conclusive; however, they may indicate that these techniques do not display the degree of accuracy required to be used operationally by the 45 WS.