There are eight technical commissions, composed of experts designated by Members, responsible for studying meteorological and hydrological operational systems, applications and research. They establish methodology and procedures and make recommendations to the Executive Council and the Congress. The technical commissions usually meet once every four years – except for the Commission for Basic Systems, which holds an extraordinary session in between. The President and Vice-President of each commission are elected at these meetings.
The eight WMO technical commissions are composed of experts in the field of the specific commission. These are designated by Members for their scientific expertise not to act as representatives on their state.