Meteorology is primarily concerned with the physical and thermodynamic state of the atmosphere.
Numerical prediction models, currently used to generate short- and medium-term forecasts (1 to 15 days), model the atmosphere using a set of thermodynamic equations and fluid mechanics equations. The measured values of the basic variables required for numerical models are mainly wind, pressure, temperature, and humidity, at ground level but especially at altitude. These measurements are carried out as far as possible in accordance with procedures recommended by the World Meteorological Organization (WMO) to maximize their representativeness.
In addition, to meet the needs of local forecasting, climatology, and real-time weather monitoring for the growing number of professional users (agriculture, aviation, transportation, public works), additional measurements are very often taken.
In situ meteorological measurements can be disrupted by their immediate environment. The exposure of sensors is therefore a key factor in their representativeness.
This article attempts to cover all of the measurements commonly taken in meteorology. In France, the physical and chemical analysis of the atmosphere is not the responsibility of meteorology and is not covered here.