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The Observatory enhances its "Automatic Regional Weather Forecast" service

16 December 2015

The "Automatic Regional Weather Forecast in Hong Kong and Pearl River Delta Region" service (website: http://maps.weather.gov.hk/ocf/index_e.html) was enhanced today (16 December 2015). In addition to the hourly forecasts of air temperature, relative humidity, wind direction and wind speed for the coming nine days, the webpage also provides forecast weather icons and daily chance of rainfall at various locations in Hong Kong (Figure 1). At the same time, rainfall nowcast is updated more frequently at six-minute intervals, to better depict the evolution of rainfall distribution in the next two hours around Hong Kong and the Pearl River Delta region.

Figure 1. Forecast weather icons (top) and forecast chance of rain (bottom)
Figure 1. Forecast weather icons (top) and forecast chance of rain (bottom)
Figure 1. Forecast weather icons (top) and forecast chance of rain (bottom)


The forecast products are generated automatically based on computer weather models and rainfall nowcasting system. The forecast chance of rainfall indicates whether it is likely to rain on the day at each location, while each forecast weather icon indicates the expected cloud cover and rainfall over a period three hours at the location. The forecast information can be presented on a map to show the regional variation, and can also be shown in a time series for the selected location (Figure 2).

Figure 2. Detailed weather information at a location.
Figure 2. Detailed weather information at a location.


The aforesaid enhancements will also be integrated into the MyObservatory mobile app in its upcoming update. Users will be able to view the automatic weather forecasts at their current location and other favourite locations easily on-the-fly.