The country is headed for depressed rainfall and warmer than usual temperatures during the short rains season of October, November to December. However the forecast released at the 11th National Climate Outlook Forum (NCOF11) indicates that the bread basket regions of the country including the North Rift, Western and Lake Victoria basin will receive near to below normal rainfall, which is set to continue through September to December.
Releasing the forecast, the Deputy Director of Meteorological Services Charles Muga said that the short rains season that “constitutes an important rainfall season for the Central and Eastern regions of the country could see poorly distributed rainfall during the season,” he said and added that, the Northeast, Southeastern lowlands and Coastal region are expected to receive below average rainfall.”
Areas expected to receive near to below average rainfall include; the South and Central Rift Valley, most of the Lake Victoria region, parts of the Highlands East of the Rift Valley including Nairobi county, some parts over Southeastern lowlands (parts of Kajiado) and western parts of Samburu and Marsabit counties, “while counties in Highlands West of the Rift Valley and parts of Northwestern are likely to receive near to above average rainfall.”
The Deputy Director who is also in charge of Aeronautical Services attributed the below average rainfall to the developing negative Indian Ocean Dipole (IOD), “which is expected to persist from September to November 2025 before returning to neutral conditions in December,” he said and added, “A negative IOD typically brings drier than normal conditions over East Africa, potentially suppressing rainfall during the short rains season,” said Muga.
And the Assistant Director of Meteorological Services Mary Kilavi noted that while the World Meteorological Organisation in its recent report indicated that there were la nina conditions developing in the Pacific Ocean at 55% during the September to November period and continue to 60 per cent, it can only affect the country’s season if it works in tandem with the Indian Ocean Dipole. “Almost all models are in agreement that, “we expect a negative Indian Ocean Dipole that is already starting to develop over the Indian Ocean and this is what affects our weather pattern resulting into depressed rainfall,” said Kilavi.
Even as this is the case, the climate scientists while comparing the prediction to the drought of 2021 in analogue years, say that the country my not experience extreme conditions due to the good rainfall performance during the March, April to May long rains season as well as the recent rainfall attributed to the Madden-Julianne Oscillation that is known to cause heavy rainfall beginning in its fourth phase of its cycle.
“On how the season will impact such sectors as agriculture production, comparing the two seasons, for example, the OND of 2021, and OND 2025, this years short rains season may not have severe impacts owing to the good rains during March, April, May, over most parts of the country, and during the June, July, August season, we had also some good rainfall over the central parts and the western parts of the country,” said Kilavi and added that “there is a possibility that it may not be as bad as the OND of 2021 was.”
According to the weatherman, the temperature outlook shows that most parts of the country are expected to be warmer than average except a few areas over the western sector where temperature is expected to be near to cooler than average. “The Central and eastern parts of the country are expected to have higher probabilities for warmer than average temperature,” said Muga in the forecast.
The onset and cessation of the rainfall will see the Western Counties (Busia, Vihiga, Kakamega, Bungoma); Nyanza Counties (Kisumu, Siaya, Homa Bay, Nyamira, Migori, Kisii); Counties in the Rift Valley; (Kericho, West Pokot, Nandi, Bomet, Uasin Gishu, Trans Nzoia, Nakuru, Elgeyo Marakwet, Baringo), rainfall continuing through September to December with the rainfall distribution expected to be fair to good.
The Counties in Central Kenya (Kirinyaga, Nyeri, Murang’a, Nyandarua, Laikipia Kiambu, Meru, Embu, Tharaka Nithi); Nairobi will see the onset of the rainfall in 3rd to 4th week of October, 2025, with the cessation expected in the fourth week of December.
The Coastal Strip counties of (Kwale, Mombasa, Kilifi, Lamu, Coastal part of Tana River) will see the onset on 3rd to 4th week of November, 2025 with the cessation expected in December. The distribution is expected to be poor.
