UW-CIMSS recently began providing real-time GOES Low-Level VIS (visible) winds in the vicinity of tropical cyclones on a demonstrational basis to NOAA's Hurricane Research Division (HRD). These data were included in many of HRD's real-time tropical cyclone surface wind analyses which were sent to forecasters at the National Hurricane Center (NHC) on an experimental basis during 1997. These wind analyses are used as guidance in their tropical cyclone advisories and warnings. The satellite observations provide essential coverage in the periphery of hurricanes where conventional in situ observations (e.g. ships, buoys, etc.) are often widely spaced or non-existent and reconnaissance aircraft do not normally fly.
The GOES Low Level VIS winds were adjusted to the surface using a Planetary Boundary Layer model. These adjusted data were used in real-time surface wind analyses for Tropical Storm Claudette and Hurricanes Danny and Erika of 1997 and were available for post-storm analyses in 1995 Hurricanes Erin and Opal as well as in 1996 Hurricanes Bertha, Fran, Hortense, (Tropical Storm) Josephine, and Lili. The satellite observations improved estimation of the 34 kt wind radii in many cases and also helped place the 50 kt wind radii for some cases. Examples of the impact of these data on hurricane surface wind analyses will be discussed as will statistics on comparisons (204 cases) of the adjusted and unadjusted GOES VIS Winds with in situ surface measurements