Development of a Post Processes Method for High-Resolution Surface Winds and Pressure for Hindcasts of Hurricane Surge

A systematic technique has been developed to post process short-term hurricane model output to improve the accuracy of surface wind and pressure fields for use by the Hurricane surge and ocean community. The method utilizes forecasts from the Navy’s operational tropical cyclone prediction model, COAMPS-TC^®, to achieve improved storm intensity and location. The high resolution (5-km) regional fields are created by merger of the moving-nests. The post processing method is demonstrated for Hurricane Sandy (2012). A combination of 6-h forecasts initialized every 6-h (from 18Z 22 Oct. to 06Z 30 Oct. 2012) reduces the track and intensity errors greatly. The intensity errors are further reduced with the calibration of maximum 10-m wind speed and minimum sea-level pressure using the interpolated hourly best track information, while maintaining their structures. Results show that the minimum sea level pressure and maximum 10-m wind speed from the calibrated fields match the best track very well, in addition to improving the track, landfall location, and timing. Surface winds are verified with buoy observations, and show that the wind distribution and timing of the storm passage agree well with the observations. Results from the Hurricane Sandy dataset are encouraging and application of this method to other storms including Hurricane Matthew (2016) will be discussed. This methodology is capable of significantly improving the surface meteorological forcing, which assists the hurricane surge and ocean wave communities to better assess hurricane impacts on the coastal environment.