Meteorological data collection in Malawi dates way back to the early 1890s when the country became a British Protectorate. Data then were recorded by administrators at the BOMAs, missionaries, farmers and a few interested individuals. Thus the station network then merely reflected the logistics of the recorders or owners of the stations rather than technical aspects. A good number of stations were sited along the Shire River and a concentration existed over the Shire Highlands in the tea estates.
Records at these stations were taken once or twice a day but at no-fixed hours. Observers were mostly untrained volunteers and as such stations did not operate consistently. For example, of the 102 stations which operated in the 1930s and 1940, only a handful were still operating by the mid 1940s, most of them only recording rainfall.
The building of a systematic network of stations under a meteorological authority begun in the mid 1940s. It was the need for aviation weather services that prompted the opening of the first few stations but soon other needs came in. Since then the logistics for sitting a station have changed and several technical aspects are considered. Apart from trying to build a homogeneous network, the Meteorological Department considers the opening of new stations for specified user parties. During the past few years stations have been opened to cater for the needs of development projects in agriculture, forestry, water resources, fisheries, wildlife, education, etc.
The present network of meteorological stations comprises 22 full meteorological stations, 21 subsidiary agrometeorological stations, strategically located in the eight ADDs. The department also runs well over 700 rainfall stations in coordination with other government departments and private organisations, of which the oldest station opened in 1891 at Zomba.
At the 22 full meteorological stations, observations are done regularly at 0500, 0600, 0800, 0900, 1100, 1400 and 1700 local times. The minimum number of observations per station is two at one-man stations and only on Saturdays and Sundays. Currently, two stations are doing observations 24 hours a day.
Observations at these stations are done by fully trained Meteorological Assistants who initially undergo a six month training course.
Stations at Chileka and Lilongwe International Airport open 24 hours daily. At Mzuzu the station opens 5 am to 6p pm daily. The rest open from 7.30 am to 5.00 pm.