The Doppler wind speeds at altitude must be adjusted to provide the equivalent of a sustained 1 m surface wind at 10 m elevation. To estimate this reduction factor we compared the Doppler velocities with quality controlled surface data from the H*Wind data base. For the region of high winds along the East coast, a reduction factor of 68 70% gave the best comparison.
Because the Doppler radar only measures the total wind speed when the wind is parallel to the radar beam, we can expect a fair estimate of the maximum wind speed when the radar beam is tangent to the eyewall. Consequently there are regions where the geometry precludes representative wind estimates. We get good estimates of wind speed in regions NW to N of the radar, which comprises the more highly populated areas of South Florida. We will extend these results to Hurricanes Frances, Jeanne and Katrina and discuss implications for estimating landfall winds in real time from the operational WSR-88D data.
Supplementary URL: http://ftp.aoml.noaa.gov/hrd/pub/dodge/Preprint_17B.2_PDodge.pdf