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Written by: Ben Or       December 2013

Have you ever pondered: "It's time for lunch. Will it be raining outside?"; "When will the rain stop?".  Maybe you have experienced: "It's raining outside the office.  Notified someone at home to shut the windows!  Yet, it turned out that there wasn't any rain at all near home.".  The "location-based rain forecast" of the mobile application "MyObservatory" is here to answer the above questions.

"MyObservatory" began to provide the "location-based rain forecast" service to the public in September 2012.  This service was developed based on the combination of the rainfall nowcast technology and the positioning service of the mobile phone.  What is rain nowcast?  It is a short-term forecast (in the next few hours) of rain and it is generated automatically by computer based on the data from weather radar.  Together with the positioning service of the mobile system, "location-based rain forecast" becomes a personalised version of rainfall nowcast!

Because of the short-term nature of rainfall nowcast, "location-based rain forecast" only provides the rain forecast in the coming two hours and the forecast is presented in text, time series of weather icons and animated rainfall forecast maps (Figure 1).  According to the Observatory's forecast verification result, the accuracy of the rain forecast in the first half hour was about 75%.  For more details on rainfall nowcast, please refer to the related technical report (in Chinese only).

Figure 1
Figure 1 "Location-based rain forecast" in text, weather icon sequence and animated rainfall forecast maps
  

When you are out for lunch next time, you may find out if there will be rain in the next couple of hours by using the "location-based rain forecast" service.  Apart from where you are, you may also set other locations in the "location-based rain forecast" (Figure 2) to get the rain forecast for other locations to enable better arrangement of daily activities or planning of outdoor activities.

 
Figure 2
Figure 2 "Location-based rain forecast" allows the selection of other locations
  
 
 

 



 

Last revision date: <20 Dec 2013>