Severe Weather Automatic Nowcast System (SWAN) is a system owned by China with proprietary intellectual property rights, which was first proposed by China Meteorological Administration in 2008, and was eventually developed by the cooperation among National Meteorological Center, Guangdong Meteorological Bureau, Wuhan Storm Office and other local meteorological departments and research institutions.

MICAPS client with Swan extension:

Considering the features of nowcast work in China, on the basis of MICAPS platform, independent live monitor and nowcast product systems were also developed. The product system of SWAN consists of live monitor data from satellites and automatic stations, various radar mosaic products (e.g. composite reflectivity, precipitation estimation, COTREC wind field, etc), monostatic radar products, several kinds of nowcast products (e.g. reflectivity forecast, precipitation forecast, STM storm identification and tracking, TITAN identification and tracking, etc), and multiple sorts of forecast verification products. SWAN client side is applicable on automatically monitoring radar characteristic quantity, thunderstorm gale, hails, barats, as well as other strong convection weather, and will send auto-alarm when necessary. The generating and release of warning information can also be achieved through this client side.

Since 2009, China Meteorological Administration has been working on the promotion and generalization of SWAN across the country, and has received positive feedbacks. In August 2014, National Meteorological Center officially released SWAN client side version 1.6, which not only inherited the original functions of the previous versions, but also provides more efficient work platform for nowcast system through improved underlying framework, optimized data processing algorithm, beautified user interface and simplified data retrieval methods.