SWIRLS Nowcast System

SWIRLS (Short-range Warning of Intense Rainstorms in Localized Systems) is the operational rainstorm nowcasting system of Hong Kong Observatory (HKO). State-of-the-art techniques are implemented in SWIRLS for analysis and prediction of precipitation and convective weather phenomena in the next few hours. SWIRLS has been in operation in HKO since 1999. SWIRLS was also implemented in various meteorological services or participated in international forecasting projects to support the research and development of rainstorm nowcasting techniques.

Under the auspicious of RSMC for Nowcasting (Hong Kong), the community version of SWIRLS, or Com-SWIRLS, is developed to facilitate knowledge exchange and cooperation on development of rainfall nowcasting technique. Com-SWIRLS can be available from this website for use by the National Meteorological and Hydrological Services (NMHSs). SwirlsPy is the codebase of Com-SWIRLS. It is a collection of tools, mostly written in Python or with Python binding, for estimating and forecasting rainfall and severe weathers (lightning, hail, gust etc.) for up to 6 hours.