Kenya Could See Heavy Rains From September as El Niño Strengthens

Kenya could face an unusually early and intense rainy season, with pre-season showers potentially arriving as early as September and heavy rainfall expected to spread across the country from October.

Climate specialist Maithya wa Vilivū said recent multi-model forecasts indicate that the October–December rains could begin several weeks earlier than usual. Early signs have already emerged in Somalia and eastern Ethiopia, where developing rain bands point to the southward movement of the Inter-Tropical Convergence Zone.

The shift typically signals the start of heavier rains across Kenya and neighbouring countries. Maithya said rainfall could intensify rapidly from early October and continue through January 2027. Some areas could receive rainfall well above the long-term average.

The forecast comes as global climate patterns could further increase rainfall across East Africa. The World Meteorological Organisation has confirmed that El Niño is strengthening and could develop into a strong event between August and October. El Niño has historically been linked to major changes in rainfall patterns around the world.

A positive Indian Ocean Dipole is also developing. The phenomenon is associated with warmer waters near East Africa and cooler conditions around Indonesia. Together, El Niño and the Indian Ocean Dipole could direct more moisture towards East Africa, increasing the risk of flooding and other weather-related hazards.

The Kenya Meteorological Service has already reported scattered showers and thunderstorms in several counties, including Nairobi, Kisumu and Nakuru. Although such conditions are not unusual at this time of year, meteorologists have warned that rainfall in the coming months could be heavier and more persistent than normal.

Prolonged rainfall could put pressure on infrastructure and drainage systems, particularly in urban areas such as Nairobi. Heavy storms can quickly overwhelm drainage networks and cause flooding.

Agriculture, transport and public health are also at risk from flooding and waterlogging. Previous El Niño events have shown how quickly livelihoods can be affected when infrastructure and emergency services come under severe pressure.

The combination of El Niño and a positive Indian Ocean Dipole could therefore pose a significant test for Kenya's preparedness. However, the exact timing and severity of the rainy season will become clearer as forecasts are updated in the coming weeks.

Experts have urged continued monitoring and early preparation as the country faces an increased risk of heavy rainfall.