23 Mar 2021

World Meteorological Day is celebrated every year on 23 March to commemorate the entry into force in 1950 of the convention that created the World Meteorological Organization. The day also highlights the contribution that national meteorological and hydrological services make to the safety and well-being of society.


World Meteorological Day takes place on 23 March every year, commemorating the establishment of the World Meteorological Organization (WMO) on 23 March 1950. As a specialized agency of the United Nations, the WMO is dedicated to international cooperation and coordination on the state and behavior of the Earth’s atmosphere, its interaction with the land and oceans, the weather and climate it produces, and the resulting distribution of water resources.

Within its mandate in the areas of weather, climate and water, the WMO focuses on many different aspects and issues from observations, information exchange and research to weather forecasts and early warnings, from capacity development and monitoring of greenhouse gases to application services and much more. It has 193 member states/territories and it works in coordination with a network of the national meteorological and hydrological services around the world.

The WMO originated from the International Meteorological Organization (IMO), founded in 1873, to facilitate the exchange of weather information across national borders. Established in 1950, the WMO became a specialized agency of the United Nations in 1951. Its mandate is in the areas of meteorology (weather and climate), operational hydrology and related geophysical sciences. Since its establishment, the WMO has played a unique and powerful role in contributing to the safety and welfare of humanity. It has fostered collaboration between the national meteorological and hydrological services of its Members and furthered the application of meteorology in many areas.

The WMO continues to facilitate free and unrestricted exchange of data and information, products and services in real- or near-real time on matters relating to safety and security of society, economic welfare and the protection of the environment. It contributes to policy formulation in these areas at national and international levels.

In addition, the WMO plays a leading role in international efforts to monitor and protect the environment through its various programs. In collaboration with other United Nations agencies and national meteorological and hydrological services, the WMO supports the implementation of a number of environmental conventions and is instrumental in providing advice and assessments to governments on related matters. These activities contribute towards ensuring the sustainable development and well-being of nations.

2021 Theme

“The ocean, our climate and weather” is the theme for World Meteorological Day 2021, celebrating the WMO’s focus in connecting the ocean, climate and weather within the Earth system. The WMO strives to support understanding of the inextricable link between ocean, climate and weather. This helps us understand the world in which we live, including the impacts of climate change, and to help Members to strengthen their ability to keep lives and property safe, reducing the risk of disaster, and to maintain viable economies.

UN Decade of Ocean Science for Sustainable Development

World Meteorological Day 2021 also marks the launch of the United Nations Decade of Ocean Science for Sustainable Development (2021-2030), which galvanizes efforts to gather ocean science – through innovative and transformative ideas – as the basis of information to support sustainable development. The Ocean Decade will harness, stimulate and coordinate interdisciplinary research efforts at all levels, in order to generate and use knowledge for the transformational action needed to achieve a healthy, safe, and resilient ocean for sustainable development by 2030 and beyond. Thus it is the opportunity to create a new foundation across the science-policy interface to strengthen the management of our oceans and coasts for the benefit of humanity.

Role of Geneva


Celebration of World Meteorological Day 2021

Online | 13:00 – 15:00 CET | WMO

Learning & Resources