More computer model forecast products available on “Earth Weather”

More computer model forecast products available on “Earth Weather”

LEUNG Yu-ting

The Hong Kong Observatory enhanced the contents of the “Earth Weather” webpage in June 2025 with the addition of products from the artificial intelligence (AI) weather forecast model “Fengwu”, including 15 days forecasts for multiple weather elements on surface and upper air to enable the public to understand upcoming weather changes.

Besides, forecasts of “Area of Potential Thunderstorm” have also been added to the webpage. This forecast product is generated by using outputs from the European Centre for Medium-Range Weather Forecasts (ECMWF) Ensemble Prediction System, indicating areas with higher potential of thunderstorm development at different times.

When users select rainfall forecasts for the ECMWF model, the “Area of Potential Thunderstorm” forecast will be simultaneously displayed with lightning symbols. The example above shows the forecast for 2:00 pm Hong Kong Time on 29 May 2025 made on 21 May, indicating a relatively high probability of thunderstorm development along the coast of southern China under the influence of a trough of low pressure.