The World Meteorological Organization says El Niño is firmly established and likely to strengthen into a very strong event, with an exceptionally high—nearly 100%—likelihood of continuing through February 2027. That global warning is serious, but it is not a day-by-day rain forecast for Kenya and should not be read as one.
Kenya’s national monthly outlook, issued on 31 August, expects September to remain generally sunny and dry across much of the country. Below-average rainfall is forecast for several western, Nyanza and Rift Valley counties, while Nairobi and much of the central highlands, eastern region and southeastern lowlands are expected to see mostly dry conditions with occasional rain.
The national picture changes as the October–November–December short-rains season begins. Kenya Meteorological Service Authority expects widespread rainfall from October, with above-average totals in many areas during October and November and the possibility of localised heavy-rainfall events. The agency’s seasonal statement says the strong El Niño can enhance rainfall, especially when it occurs alongside a positive Indian Ocean Dipole.
That second climate driver still carries uncertainty. Kenya’s 26 August technical statement said the Indian Ocean Dipole was neutral on 23 August and was expected to rise above the positive threshold, but the timing and strength were not certain. This is why a powerful El Niño cannot be translated into the same impact for every county, river basin or week.
WMO makes the same caution explicit at the global level: a very strong El Niño increases the likelihood of major shifts in rainfall and temperature, but local impacts depend on season, location and other ocean-atmosphere patterns. National meteorological services remain the authoritative source for local warnings, while county advisories and short-range forecasts should guide immediate decisions.
Preparedness should therefore run on two tracks. Farmers and pastoralists can use September’s dry intervals to conserve water and fodder, protect mature crops and repair water-harvesting structures. County governments and urban residents can clear drainage, inspect bridges and culverts, map flood-prone roads and prepare evacuation and communication plans before the heavier short rains begin.
Nairobi’s September outlook is not a promise of uninterrupted sunshine. Occasional showers, colder mornings and strong winds can still create local hazards, and a monthly forecast cannot replace a current warning. Residents should check daily and five-day bulletins before travel, outdoor events or construction work.
The useful message is neither panic nor complacency: September is expected to be largely dry in much of Kenya, but the window for preparing for a wetter October and November is already open. The strongest forecast is the one updated closest to the place and time of the decision.
