A new era in hurricane reconnaissance: Real time measurement of surface wind structure and intensity via microwave remote sensing

The Stepped Frequency Microwave Radiometer (SFMR), flown on the NOAA WP-3D aircraft was used in Hurricane Dennis, 1999 for the first time to measure, process and transmit surface wind and rainrate information to the National Hurricane Center. There the observations were injested into the Hurricane Research Division's real time surface wind analysis package to produce a surface wind analysis. Analyses were produced in phase with the hurricane forecasters 3-hourly advisory cycle. Forecasters used this information to determine actual surface sustained gale force, storm force and hurricane force wind radii as well as surface peak sustained wind and radius of maximum surface wind, which then formed the basis for advisories and warnings on peak wind and outer wind structure. SFMR data were compared with GPS dropsonde surface wind observations for 1998-99 storms and nearby moored buoy and CMAN observations, showing excellent agreement, except over the Gulf Stream region. Future plans will be discussed.