Doppler Wind Analysis of Hurricane Gloria

摘要

Real time analysis of the radar data using the NEXRAD wind analysis algorithm (VAD) showed the winds to be significantly less than those forecast by the National Hurricane Center, and this result was passed to the National Weather Service Forecast Office in Boston. The wind analysis algorithm provided vertical profiles of the wind in the vicinity of the AFGL radar in Sudbury, MA (approximately 36 km west of Boston). Profiles were obtained approximately every 8 minutes and provided information up to heights of 5-6 km. The location of the maximum wind was observed to approach the surface during the morning hours, and the maximum surface winds occurred between 1200 and 1430 EST. Maximum low level Doppler winds coincided with observed winds at the Blue Hill Observatory in Milton, MA (approximately 36 km at 126 deg azimuth from radar) as well as the radar site. Twenty-five m/s winds or greater were observed to descend from a height of 4 km at 0700 EST, through 1.5 km at 0730 EST, to 0.6 km at 1045 EST, and finally at 0.2 km at 1241 EST. These trends in the winds derived from the wind analysis algorithms are discussed along with additional sectorized wind analyses and suggested operational uses of those types of information.