The World Meteorological Organization (WMO) is an intergovernmental organization with a membership of 189 Member States and Territories. It originated from the International Meteorological Organization (IMO), which was founded in 1873. Established in 1950, WMO became the specialised agency of the United Nations for meteorology (weather and climate), operational hydrology and related geophysical sciences. It has its headquarters in Geneva, Switzerland and is a member of the United Nations Development Group. The current president is David Grimes and the current Secretary-General is Michel Jarraud.

The World Meteorological Organization (WMO) is a specialized agency of the United Nations. It is the UN system's authoritative voice on the state and behavior of the Earth's atmosphere, its interaction with the oceans, the climate it produces and the resulting distribution of water resources.

WMO has a membership of 189 member states and territories (since 4 December 2009). The Convention of the World Meteorological Organization was signed 11 October 1947 and established upon ratification in 1950. WMO became the specialized agency of the United Nations in 1951 for meteorology (weather and climate), operational hydrology and related geophysical sciences. It originated from the International Meteorological Organization (IMO), which was founded in 1873.