NAIROBI, Kenya Oct 19 – Kenya is bracing for an increasingly wet October–December season, with the Kenya Meteorological Department forecasting rainfall across dozens of counties this week as the country prepares for the potential effects of a strengthening El Niño.
The latest seven-day forecast, covering October 20 to 26, predicts rainfall in parts of Meru, Embu, Baringo, Bomet, Bungoma, Busia, Elgeyo Marakwet, Garissa, Homa Bay, Kakamega, Kericho, Kiambu, Kilifi, Kirinyaga, Kisii, Kisumu, Kitui, Kwale, Laikipia and Lamu.
Others include Machakos, Makueni, Mandera, Marsabit, Migori, Mombasa, Murang’a, Nairobi, Nakuru, Nandi, Narok, Nyamira, Nyandarua, Nyeri, Siaya, Taita Taveta, Tana River, Tharaka-Nithi, Trans Nzoia, Turkana, Uasin Gishu, Vihiga, Wajir and West Pokot.
The department cautioned that rainfall distribution would vary across counties, meaning some areas could receive significantly more rain than others.
Isolated storms are also possible in parts of Kitui, Makueni, Kajiado, Machakos, Laikipia, Samburu, Mandera, Wajir and Marsabit, raising the possibility of localised downpours in areas already vulnerable to flash floods.
The forecast also points to contrasting temperature conditions, with daytime average maximum temperatures exceeding 35 degrees Celsius in parts of Garissa, Wajir, Tana River, Isiolo, Kilifi, Marsabit, Samburu and Turkana.
Night-time average minimum temperatures are expected to fall below 10 degrees Celsius in some areas of Meru, Tharaka-Nithi, Nyeri, Kirinyaga, Murang’a, Nakuru and Kajiado.
The weekly outlook comes as meteorologists maintain their forecast for enhanced rainfall during the October–November–December short-rains season, with El Niño expected to influence weather patterns across East Africa.
El Niño raises flood concerns
The Intergovernmental Authority on Development’s Climate Prediction and Applications Centre (ICPAC) said in its August 18 regional outlook that the Greater Horn of Africa was likely to experience wetter-than-normal conditions during the October–December season.
The agency attributed the outlook to an El Niño event that had developed in the Pacific Ocean and was expected to strengthen, alongside the anticipated positive phase of the Indian Ocean Dipole (IOD).
“These conditions normally lead to enhanced rainfall over the region during the OND season,” ICPAC said.
The regional outlook identified central Kenya and the Lake Victoria Basin among areas with a high likelihood of seasonal rainfall exceeding 400 millimetres. However, the agency cautioned that the timing and distribution of rainfall would differ across the region.
Kenya Meteorological Department officials have also warned that the strength of El Niño alone does not determine how much rain the country receives.
Speaking during a preparedness meeting in Narok, the county’s Director of Meteorological Services, Stanley Kinyua, said the Indian Ocean Dipole would be a key factor in determining the intensity of the coming rains.
“The outcome of the season will majorly depend on the strength of the IOD,” Kinyua said.
The Indian Ocean Dipole is a climate pattern involving differences in sea-surface temperatures across the Indian Ocean. Depending on its phase and strength, it can amplify or moderate the rainfall effects associated with El Niño.
Warnings over flooding and infrastructure
The anticipated rains have heightened concerns about flooding, landslides, damage to roads and other infrastructure, and the displacement of households in vulnerable areas.
Kenya experienced devastating flooding during the 1997–1998 El Niño period. More recently, heavy rains during the 2023–2024 season caused deaths, displaced families and damaged infrastructure in several parts of the country.
Authorities have cautioned that the effects of heavy rainfall can be worsened by poor drainage, inadequate sanitation, weak housing and settlement along riverbanks and floodplains.
The Ministry of Health has also activated preparedness measures ahead of the anticipated rains, warning that flooding can contaminate water sources and create conditions that favour the spread of waterborne diseases, including cholera and typhoid, as well as mosquito-borne illnesses.
The National Government and county administrations have been urged to strengthen early-warning systems, coordinate emergency responses and ensure communities receive timely information.
Farmers urged to follow forecasts
The rains could improve soil moisture, replenish water reservoirs and support crop production and pasture regeneration, particularly in areas that have experienced dry conditions.
However, prolonged wet spells and intense downpours could also cause waterlogging, soil erosion, crop losses and disruption to transport, making localised forecasts important for farmers and other sectors.
The Kenya Meteorological Department advises the public to rely on its regular weather updates rather than assume that all areas will receive similar amounts of rainfall.
Although El Niño is associated with enhanced rainfall in East Africa, it does not mean that heavy rain will occur continuously or uniformly across the country. The latest seven-day forecast provides a more immediate guide to expected conditions, while the seasonal outlook indicates the broader rainfall pattern anticipated through December.