Initial Results From The Navy Two-Way Interactive Nested Tropical Cyclone Model

Abstract

A primitive equation, two-way interactive nested tropical cyclone model has been developed by the Naval Environmental Prediction Research Facility for operational use during the 1980 typhoon season. The fine mesh grid of the model operates interactively with a larger area tropical prediction model, and is initialized with both real data and bogus information obtained from an empirical typhoon model. Tests with 40 real data cases are summarized, and results indicate considerable skill in forecasting tropical cyclone position. Mean vector errors of 159 km (87 n mi), 271 km (148 n mi) and 443 km (242 n mi) for 24, 48 and 72 h position forecasts have been achieved for the test cases. The model will be used to provide objective forecast guidance to DOD forecasters at the U.S. Naval Oceanography Command Center/Joint Typhoon Warning Center, Guam.