Impact of FORMOSAT-3/COSMIC GPS radio occultation and dropwindsonde data on regional model predictions during the 2008 Mei-yu season

This paper presents the result of a cooperative study under the Integrated Research Project of FORMOSAT-3/COSMIC and SoWMEX (Southwesterly Monsoon Experi-ment) in Taiwan during the 2008 Mei-yu season. The main purpose is to examine the impact of FORMOSAT-3 GPS RO data and dropsonde data on regional weather predic-tion. The WRF model and its 3DVAR component, WRF VAR, are used for evaluation on the forecast of heavy rainfall events associated with Mei-yu fronts in Taiwan. We compare the numerical simulations with and without each set of the data to study the impact of these extra data on regional weather prediction.