The Department of Climate Change and Meteorological Services said this through a press release.
“During October to December 2016, the greater part of southern half of the country is expected to have normal to above normal rainfall amounts while the greater part of northern half will have normal to below normal. During the period January to March 2017, the greater part of the country is expected to experience normal to above normal rainfall amounts. Overall, the greater part of the country is going to experience normal to above normal rainfall amounts during October 2016 to March 2017,” said the statement in part adding that while many areas of the country will experience good rainfall, flooding and dry spells are likely to occur in some areas during the 2016-2017 season.
The statement added that, in recent years, the rainfall seasons which were affected by a weak La Niña phenomenon of almost similar strength like 2016-2017 rainfall season are 1983-1984 and 2005-2006 seasons.
“Climatic analyses on these weak La Niña years show that the country experienced normal cumulative rainfall amounts. However, a greater part of the southern half of the country experienced above normal rainfall amounts while some parts in the northern half experienced below normal rainfall amounts,” adds the statement.
The department further said that the main rains start from November in the South and progressively spread northwards. During this period, the main rain bearing systems that influence rainfall over Malawi include the Inter-Tropical Convergence Zone (ITCZ), Congo air mass, Easterly Waves and Tropical Cyclones.
Sea Surface Temperatures over the Pacific, Indian and Atlantic tropical Oceans are the key driving factors on rainfall systems in Malawi. So far, a weak La Niña phenomenon has developed over the Eastern Central Equatorial Pacific Ocean and is expected to persist up to early 2017. La Niña, unusual cooling of waters over the Eastern Central Equatorial Pacific Ocean, affects rainfall pattern over the world including Southern Africa and Malawi.
The department has however urged farmers in the country to seek advice from the Ministry of Agriculture, Irrigation and Water Development when applying this forecast in decision making such as when to plant.
The period October to April is the main rainfall season in Malawi.