A barograph is a recording aneroid barometer. It produces a paper or foil chart called a barogram that records the barometric pressure over time.
Barographs are recording barometers. They display the trend (up, steady, or down) and the rate of change. And since changes in pressure generally precede new weather, a barograph can help us "see" what's coming. For instance, rising pressure most often indicates clearing and cooler; falling pressure usually points to warmer, more cloudy, and possible precipitation. A rapid rise or fall is almost always accompanied by higher winds, and unchanging pressure means continuing conditions and little wind. The crest or trough of a pressure curve most often indicates a change of wind direction. With these few forecasting tips you can use a barograph as your crystal ball.
Barograph showing the strong drop in barometric pressure due to TS Ivan, Sept. 16, 2004
