Even the best barometer tells only the current pressure - no more.
Knowing the pressure is like knowing the Dow Jones average for any one
moment: we really need to know which way it is heading, and how fast.
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.
ALTITUDE affects your barograph, as well as your barometer. Most
instruments will function properly up to 2500', some higher. We are
prepared, at no charge, to compensate your barograph for altitude, if
possible. Please contact us for advice before making your selection.