A Guide to Weather Forecasting using a Barometer

The barometer will give a much better guide to weather forecasting if account is taken of the rate at which the pressure rises and falls as well as the information on the dial. Most barometers have two pointers for this purpose: one is set by hand to align with the other, the moving pointer, each night (or whenever is convenient). In the morning, the change in pressure can be observed by the difference between the two pointers and, by using the information given below, you can make your own local weather forecast. This is for the northern hemisphere, for the southern hemisphere, reverse north and south.

A Rising Barometer Pressure

A rapid rise indicates unsettled weather

A gradual rise indicates settled weather

A rise, with dry air, and cold increasing in summer, indicates wind from the north; and, if rain has fallen, better weather is coming

A rise, with moist air and a low temperature, indicates wind and rain from the north

A rise with a southerly wind indicates fine weather

A Steady Barometer

With dry air and seasonable temperatures, indicates a continuance of very fine weather

A Falling Barometer Pressure

A rapid fall indicates stormy weather

A rapid fall with westerly wind indicates stormy weather from the north

A fall with a northerly wind indicates storm, with rain and hail in summer, and snow in the winter

A fall with increased moisture in the air and the heat increasing, indicates rain and wind from the south with the possibility of thunder

A fall with dry air and increasing cold in winter indicates snow

A fall after very calm and warm weather indicates rain and squally weather with the possibility of thunder.