Kenyans warned of abnormal rains as strong El Niño intensifies
By Valerian Khakayi, August 13, 2026Kenyans have been warned to prepare for an early onset of unusually heavy rains, with experts cautioning that the 2026 October-November-December (OND) rainy season could bring significant rainfall across the country.
Weather expert Maithya wa Vilivū said the signs of the approaching rainy season were already becoming clearer, with pre-seasonal rains expected to begin in parts of Kenya as early as September.
According to Maithya, the August multi-model super-ensemble forecasts point to an early onset of pre-seasonal rains, particularly in northeastern Kenya and the coastal region.
He said similar rains could also affect Somalia, Somaliland and northern Tanzania’s coastal strip during September.
“One of the key parameters that we use to know when the OND rainy season will begin is the consistent emergence of rain bands in Eastern Ethiopia, Somali Land & Somalia,” Maithya said.
“The August multi-model super-ensemble runs are out, and it’s now clearer than ever before that there will be an early onset of pre-seasonal rains this time round, particularly in Somalia, Northeastern KE & the Kenyan Coastal Strip in Sept 2026.”
Abnormal rains
Maithya explained that one of the key indicators used to determine the onset of the OND rainy season is the consistent emergence of rain bands over eastern Ethiopia, Somaliland and Somalia.
The weather expert added that the rain bands also signal changes in the direction and strength of Indian Ocean trade winds, marking the end of the West Indian Ocean Monsoon.
“These bands normally indicate a southward shift of the Inter-Tropical Convergence Zone (ITCZ) from the Sahel & Ethiopian highlands into Equatorial Africa, including KE. They also signify a change in the direction and strength of the Indian Ocean trade winds, bringing to an end the West Indian Ocean monsoon. Tropical disturbances in the Indian Ocean are also something to watch,” he explained.
He further noted that tropical disturbances in the Indian Ocean would be among the factors to watch as the rainy season approaches.
Maithya said the expected September rains could intensify quickly and spread to other parts of Kenya from early October.
The rains are then expected to continue through the OND season and into January 2027, potentially bringing prolonged wet conditions across various parts of the country.
El Niño
The warning comes amid concerns over the combined influence of El Niño and the Indian Ocean Dipole (IOD).
Maithya said global multi-model ensemble charts were projecting above-average rainfall in September in some of the affected regions, with rainfall totals in certain areas potentially reaching up to 20 millimetres above the long-term average.
He cautioned that the rainfall could become particularly concerning because of what he described as a strongly established El Niño in the Equatorial Pacific and the IOD entering a positive phase.
“These rains are coming at a time when a record-breaking strong El Nino is firmly established in the Equatorial Pacific and the IOD is entering a positive phase, meaning they could easily turn into a catastrophe,” he said.
The combination could increase the risk of flooding and other weather-related impacts, particularly in areas that experience heavy rainfall.
However, Maithya noted that short-range and sub-seasonal forecasts would provide a clearer picture of the exact timing and intensity of the rains in the coming weeks.
He urged Kenyans to continue monitoring updated weather forecasts as September approaches and preparations for the 2026 OND rainy season intensify.