Analysis of Hydrometeors for WRF: Variational Assimilation of Satellite Cloud Products and Radar Observations

In this study, analysis of hydrometeors for the Weather Research and Forecasting (WRF) model and its impact on short-term regional numerical weather prediction are presented. Variational data assimilation system for WRF (WRFDA) is further developed to produce cloud liquid water and ice water analysis by directly assimilating cloud liquid water and ice water path products from satellite observations. Two 10-day continuously 3 hourly cycling data assimilation and forecast experiments with/without use of the cloud water path are conducted. It is shown that assimilation of cloud water path significantly reduces 24-h forecast errors in temperature about 200 hPa and near surface levels. The humidity and precipitation forecast skills are improved up to 24 hours as well. In addition, recent work on cloud product assimilation and radar data assimilation using Variational Local Analysis and Prediction System (VLAPS) will be also presented.