An irrigation system includes a radio transmitter station that transmits weather prediction information to a geographic region that includes multiple geographic sub-regions. The weather prediction information includes a respective geographic sub-region code for each of the geographic sub-regions for which a weather forecast predicts rain within a predetermined time period. An irrigation apparatus in a particular sub-region activates to water a watering zone at a schedule time. However, if the irrigation apparatus receives the sub-region code for the particular sub-region where the irrigation apparatus is located, the irrigation apparatus does not immediately activate to water the watering zone in one embodiment. The transmitter station may transmit both program content and data content on a common radio frequency signal wherein the data content includes the weather prediction information.