Residents of Nairobi and other Kenyan regions have reported unusually hot days even as the October‑December rainy season begins, prompting questions about the expected cooling effect of El Niño.

Weather expert Maithya wa Vilivū notes that seasonal climate models project Nairobi’s temperatures to remain 0.5 °C to 1.5 °C above normal through the final quarter of 2026 and into early 2027, with a median rise of about 1.1 °C.

Vilivū attributes the uncertainty in rainfall timing to the interaction of El Niño with other climate systems such as the Indian Ocean Dipole, Madden‑Julian Oscillation, Kelvin waves and tropical storms, which affect moisture transport and rainfall distribution.

Experts stress that while El Niño typically brings increased rainfall to East Africa, the presence of these additional climate drivers means rain may be uneven or delayed, allowing hot, sunny conditions to persist in Nairobi during the rainy season.

The IGAD Climate Prediction and Applications Centre forecasts enhanced rainfall across much of the Greater Horn of Africa for October‑December, but expects the timing and spatial distribution of showers to vary by location.

Kenya Meteorological Service Authority (KMSA) officials explain that delayed rainfall onset in some areas does not alter the seasonal forecast, and that El Niño’s strength alone cannot determine the amount of rain any specific locality receives.

For the week of 20‑26 October, the Kenya Met forecast maximum daytime temperatures above 35 °C in Garissa, Wajir, Tana River, Isiolo, Kilifi, Marsabit, Samburu and Turkana, while Nairobi is expected to reach a high of 29 °C and a low of 12 °C.

Global climate monitoring by Reuters’ Heat Storm Tracker indicates that heat storms now cover roughly a third of the planet, affecting 1.7 billion people, underscoring the broader context of rising temperatures worldwide.