A numerical study of the effect of GOES sounder cloud-cleared brightness temperatures on the prediction of Hurricane Felix

The influence of Geostationary Operational Environmental Satellite (GOES) b rightness temperature data on the numerical simulations of Hurricane Felix is investigated. Satellite data are included as an augmentation to a bogus data assimilation (BDA) procedure using a mesoscale adjoint modeling system . The assimilation of satellite data modified not only the environmental fl ow but also the structure of the initial vortex, which is located over a re gion devoid of satellite data. This modification resulted in a reduction of the 12-h forecast errors verified by radiosonde data. Despite the fact tha t the forecast using only the bogus surface low at the initial time was ver y good, track and intensity forecasts beyond 2 days of model integration we re shown to be improved further by including satellite data in the initiali zation procedure. Differences in the prediction of Hurricane Felix with and without satellite data were also found in the prediction of the upper-leve l jet, the cold temperature trough ahead of the hurricane, the size of the hurricane eye, and the location of the maximum hydrometeor. Although the fo cus of this study is to assess the effect of the direct use of satellite br ightness temperature data on hurricane prediction, it is also noted that th e BDA experiment including only the bogus data shows a positive effect of t he BDA vortex on the environmental flow during the forecast period, as veri fied by satellite observations.