NAIROBI, Kenya — The Kenya Meteorological Department has attributed the unusual rains experienced in February to a tropical weather system known as the Madden–Julian Oscillation (MJO).
Director General Edward Muriuki said the recent showers were triggered by the oscillation, a tropical disturbance that moves eastward around the globe and significantly influences rainfall patterns in equatorial regions.
“In the past two weeks, we have experienced some off-season rains that have been occasioned by a tropical disturbance that moves in an easterly direction, which is known as Madden-Julian Oscillation,” Muriuki said during an interview on Citizen TV on Monday.
He explained that the phenomenon, discovered in 1971, has two phases — one that suppresses rainfall and another that enhances it.
“So in the last two weeks, it has enhanced our rainfall,” he added.
Transition to Long Rains
Muriuki clarified that although Kenya is approaching the March–April–May long rains season, the showers witnessed in late February were technically off-season.
He said the country is now transitioning into the long rains period, with widespread rainfall expected from March through April before tapering off in May.
Kenya experiences two main rainy seasons annually: the long rains from March to May and the short rains between October and December.
“Currently, the country is in transition to the March, April and May long rains season. Kenya experiences two major seasons — March, April and May and then October, November and December,” he said.
The Kenya Met boss noted that these rainfall patterns are largely influenced by the movement of the Intertropical Convergence Zone (ITCZ), a low-pressure belt that shifts north and south in line with the position of the sun.
Flood Risk in 22 Counties
The department has warned of heavy rainfall in 22 counties starting Tuesday, cautioning that the downpour could trigger flooding in some areas.
Counties expected to be affected include Kisumu, Siaya, Busia, Migori, Homa Bay, Kisii, Nyamira, Kakamega, Bungoma, and Vihiga.
In the Rift Valley region, Nakuru, Baringo, Kericho, and Bomet are also projected to receive heavy rains. In the highlands east of the Rift Valley, Nairobi, Kiambu, Nyeri, Murang’a, Kirinyaga, Embu, and Meru are on alert.
Authorities have urged residents in low-lying and flood-prone areas to remain vigilant as the country enters the peak of the long rains season.
