10.2 Development of a cloud nowcasting system

Auligne, Tom, Dongmei Xu, and Jose Ruiz-Arias, National Center for Atmospheric Research

The initialization of cloud parameters is the next frontier for improving short-term prediction skills in numerical weather prediction models. We will present the latest developments in building a capability to accurately initialize cloud microphysical parameters in WRF, based on satellite observations. Retrieved cloud optical properties and raw satellite radiances from multiple infrared and microwave sensors are assimilated. The prototype uses a hybrid ensemble/variational data assimilation system with an augmented control variable for clouds, multivariate background errors and specific developments to address non-linearities and non-Gaussian error distributions related to cloud parameters. The impact of the cloud initialization on subsequent forecasts is studied.