The document discusses using weather-based advertising (WBA) to improve banner ad campaigns. WBA allows advertisers to create different banners targeting specific weather conditions that may influence sales. The banners are served to users based on the current weather in their city or region. Advertisers can define relevant weather categories, create banners for each, and the system will automatically serve the appropriate banners based on live weather data. WBA aims to increase banner relevancy and performance by matching ads to the mood of consumers based on the current weather conditions.