A new product, "Isobaric Chart with Satellite Image", was launched today (29 October 2007) by the Hong Kong Observatory in its website (http://www.weather.gov.hk/wxinfo/currwx/wxcht.htm). An isobaric chart is an analysis of the atmospheric pressure pattern at the earth surface, depicting the positions of high and low pressure centres, weather fronts and tropical cyclones, etc. The new product, with satellite images automatically superimposed onto isobaric charts by computer, will show the close relationship between weather systems and cloud clusters. The picture will help to promote a better understanding of how different weather systems bring about different weather conditions.