The radar service is extraordinarily popular. The Bureau says more than three quarters of the 200,000 discrete visitors that use its site daily go to the service, which has served more than 850 million individual http:// requests for images and HTML in a single month. The rain radar covers all capital cities and offers a map covering a 250km radius that shows where it is raining and at what intensity. The service even offers a short animation so users can see which direction showers are moving.
The upgrade has seen the Bureau replace hand-drawn maps with new charts drawn using geospatial data to enhance accuracy and showing topographical features such as height contours. The number of locations on each city's map has been increased to give viewers a better chance to understand how hard it is raining near their homes or businesses. Numerous requests from Sydney residents even resulted in the addition of Waragamba Dam to the city's radar service. The dam is at an all time low and residents keenly await news of rainfall in the dam that could result in the lifting of water restrictions.
"The public demanded background topography because thunderstorms form on higher ground and people like to see the causative mechanisms at work," the bureau's co-coordinator of public and marine weather services for NSW, Julie Evans, says. "Our peak demand is in summer when people want to watch storms online".
Other requests came from the vision impaired. The new site now displays 15 different levels of rain intensity, up from the previous six, and the Bureau now deliberately uses a palette of colors colorblind users find easier to view.
"We are very conscious of accessibility guidelines," Evans says. "The new colour scheme intuitively follows the rainbow and takes out magenta to help the colour-blind".
The enhancements are expected to drive even more traffic to the radar service, which launched in December 2000 and attracted just 50 million hits in its first year of operation.
"Further down the track we are considering overlays so users can switch different data sets on and off to get their own views," Evans concluded. "As browsers get better features, we'll look at ways to deliver more services".