In 1947 Carl-Gustaf Rossby arrived to Sweden from the United States to strengthen research at the newly created Department of Meteorology (MISU) at Stockholm University.

 
Carl-Gustaf Rossby
Carl-Gustaf Rossby (1898-1957)
 

Before returning to Sweden, Rossby had been head of research for the Weather Bureau and head of the Department of Meteorology at the Massachusetts Institute of Technology. In 1955, the International Meteorological Institute in Stockholm (IMI) was created by a decision of the Swedish Parliament with the objective "to conduct research in meteorology and associated fields and to promote international scientific co-operation within meteorology". Since then, IMI and MISU have formed a symbiotic organization, up to 1973 physically located in central Stockholm. Since 1973 they are located at the university campus Frescati north of downtown Stockholm.