Full Answer. An increase in the reading on the barometer signifies a rise in the air pressure, which leads to good weather, while a decrease in this reading means that the air pressure is falling, a clear signal that bad weather has arrived or is on the way. Typically, once a storm has moved through a region, the barometric pressure should begin to rise again.What is weather pressure?
Weather pressure or rather atmospheric pressure is measured in millibars. These are thousandths of a bar of pressure which is the atmospheric standard pressure. Thus 1000 millibars is average atmospheric pressure.What is a precipitation forecast?
The quantitative precipitation forecast (abbreviated QPF) is the expected amount of melted precipitation accumulated over a specified time period over a specified area.