Surface pressure is a significant feature of interest since low pressures indicate rising vertical motions which usually leads to clouds and precipitation, while high pressures signify downward vertical motion giving fair weather. Temperatures are important for indicating the type of air mass. Winds are also important in showing where and how fast the air is propagating. The dewpoint temperature represents how much water vapor is in the air. The dewpoint temperature is the temperature the air would need to be cooled to become saturated.
Saturation is required for the formation of clouds and precipitation.
Television and radio reports typically focus on surface weather forecasts, such as a cold rainy day. What is not explained are the conditions above the surface, which are of vital importance in weather forecasting. For this reason it is vital to analyze weather conditions at the Earth's surface and the conditions aloft. Weather balloons are simultaneously launched from certain National Weather Service stations all over the United States. The balloons rise up high into the atmosphere, taking measurements throughout.