[--MAIN HOME--] [--ALL HABYHINTS--] [--FACEBOOK PAGE--] HABYTIME MINI LECTURE 8: RIDGES METEOROLOGIST JEFF HABY A ridge is a region of higher heights aloft (often analyzed at 500 and 300 mb). The ridges discussed here are the large size ridges that are associated with the jet stream. They can be large enough to cover part or most of the United States. The region of higher heights is created from the troposphere being relatively warmer in temperature. Warm air is less dense and thus the height of the troposphere is greater when the air is warmer since warmer air occupies a greater volume of space. Ridges have a significant impact on the weather. Generally warmer than normal weather will occur for the region under the influence of the ridge. The region influenced by the ridge generally has sinking air and warmer than normal weather. Sinking air warms adiabatically. Sinking air also stabilizes the troposphere. If a ridge influences a region for an extended period of time it can lead to below normal precipitation and drought. Ridges can also follow the weather associated with a trough, thus weather can change from cloudy / stormy to clear / sunny when a ridge replaces a trough.