Hurricane Katrina's wind field: Synthesizing wind observations to construct an analysis of record

As the most costly U.S. natural disaster in history, Hurricane Katrina has fostered a variety of forensic studies to better understand the event. All available observations from several hundred space-, land-, sea-, and aircraft-based measurement platforms were gathered and processed to a common framework for height, exposure, and averaging time, to produce a series of wind field snapshots at 3h intervals to depict the wind structure of Katrina when in the Gulf of Mexico. The Stepped-frequency microwave radiometer (SFMR) was calibrated against GPS sondes to establish the upper range of the instrument and then used to determine the wind field in the storm's core region in concert with airborne Doppler radar winds adjusted to the surface from near the top of the PBL (500 m). The SFMR data were used to develop a method to estimate surface winds from 3 km level reconnaissance aircraft observations, taking into consideration the observed azimuthal variation of the reduction factor. The "SFMR method" was used to adjust AFRC recon flight-level measurements to the surface in the core region when SFMR and Doppler winds were not available. A variety of coastal and inland mesonet data were employed, including portable towers deployed by Texas Tech University, University of Louisiana at Monroe, and the Florida Coastal Monitoring Program, as well as fixed mesonet stations from Louisiana State Universities Marine Consortium, University of Southern Mississippi, University of South Alabama, and Agricultural Networks from Louisiana, Mississippi, and Alabama, and the Coastal Estuarine Network of Alabama and Mississippi. With the inclusion of land- (WSR-88D VAD and GBVTD, ASOS, Metar, LLWAS, HANDAR), space- (QuikScat, GOES cloud drift winds, WindSat), and marine- (GPS sondes, Buoys, C-MAN, ships) platforms, the wind field reconstruction of Hurricane Katrina will represent the most comprehensive study undertaken for a landfalling hurricane since Andrew of 1992. The wind fields will serve as an analysis of record and will be used by a variety of wave and storm surge models to produce hindcasts of water levels in the vicinity of flood control structures. With a robust future observing system, we envision an analysis system that will provide seamless delivery of detailed information at landfall to help fill the critical gap between the forecast and the event itself.