Development of an advanced aviation nowcasting system in support of air traffic management by blending radar nowcasting data with NWP forecasts
Due to the limitation of the extrapolation technique, ATNS can only provide reliable forecasts up to one to two hours ahead. In order to extend the forecast period and to capture the evolution of thunderstorms, the blending of the radar-based nowcasting data with the forecasts from a rapidly updated Numerical Weather Prediction (NWP) model has also been explored by HKO so that the thunderstorm forecasts could be usable up to 6 hours ahead. The NWP model under testing is a high-resolution (horizontal resolution of 5 km), non-hydrostatic model. The blended nowcast-NWP system is named Advanced Aviation Nowcasting System (AANS). Case studies indicate that AANS could improve the forecasts at T+1 hour and beyond. This paper presents the concept of AANS under development and provides some preliminary performance results.