Kenya Met Forecasts Below-Average Rainfall in Several Counties in September

The Kenya Meteorological Service Authority (KMSA) has forecast below-average rainfall in several counties during September 2026, with dry conditions expected to persist across large parts of the country.

The forecast, issued on Wednesday, September 2, indicates that rainfall patterns in September will vary across the country, with some areas expected to receive near-average rainfall while others experience generally sunny and dry conditions.

Kenya Met said September is a transition month between the generally dry June-July-August season and the October-November-December short rains.

"September marks the climatological transition period from the June-July-August season that is generally dry over most parts of the country, to the October-November-December short rainfall season," the forecast read.

According to Kenya Met, below-average rainfall is likely over Trans Nzoia, Bungoma, Busia, Kakamega, Siaya, Vihiga, Nandi, Uasin-Gishu, Elgeyo-Marakwet, West Pokot, Kisumu, Kericho, Nyamira, Kisii, Bomet, Migori and Homa Bay counties. 

Parts of Narok, Nakuru, Baringo and Turkana are also expected to record below-average rainfall.

Near-average rainfall is forecast in Lamu, Kilifi, Mombasa and Kwale counties, as well as parts of Tana River, Mandera, Wajir and Garissa.

Generally sunny and dry conditions, with occasional rainfall, are expected in Nairobi, Kiambu, Murang'a, Nyeri, Embu, Meru, Tharaka-Nithi, Kirinyaga, Nyandarua, Laikipia, Makueni, Kitui, Machakos, Taita-Taveta, Kajiado, Marsabit and most parts of Wajir, Mandera, Garissa, Narok, Nakuru and Turkana.

Kenya Met also said most parts of Isiolo, Turkana and Samburu are expected to experience generally sunny and dry conditions.

The weather outlook is also expected to have implications for agriculture and livestock in several counties. 

Below-average rainfall in parts of western Kenya and the Rift Valley may create conditions conducive for harvesting, although prolonged dry conditions could worsen food, water and pasture shortages.

"There may be a shortage of food, water and pasture in these areas due to the dry period experienced in the previous months that led to loss of crops," the forecast added.

Kenya Met said sunny and dry conditions expected in Laikipia, Makueni, Kitui, Machakos, Marsabit, Wajir, Mandera, Garissa, Isiolo, Taita-Taveta, Kajiado and parts of Narok and Tana River could result in pasture and water shortages.

The forecast also highlights possible effects on transport and infrastructure; intermittent rainfall in Kwale, Lamu, Mombasa and Kilifi could make roads slippery and affect construction activities.

Fog formation in Nyandarua, Laikipia, Nyeri, Kirinyaga, Murang'a, Kiambu, Meru, Embu, Tharaka-Nithi and Nairobi could reduce visibility and pose risks to motorists. 

The fog may also occasionally disrupt operations at Wilson and Jomo Kenyatta International airports.

The health sector could also be affected by the anticipated dry conditions, particularly in arid and semi-arid areas.

"The expected dry weather conditions may lead to an increase in respiratory diseases in Garissa, Mandera, Marsabit, Isiolo, Taita Taveta, Wajir, and Tana River Counties," the forecast further read.

Strong winds and dry weather could generate dust storms, potentially aggravating respiratory problems and increasing the risk of eye infections.

Kenya Met added that several ASAL counties, including Isiolo, Garissa, Turkana, Baringo and West Pokot, remain under drought stress. 

The anticipated dry conditions could reduce pasture and water availability, lower livestock productivity and worsen food insecurity in these areas.

Kenya Met further warned that the situation could contribute to increased acute malnutrition, longer distances for water access and heightened disease risks.

Water resources are also expected to come under pressure in Mandera, Wajir, Isiolo, Marsabit, Garissa, Turkana and Samburu because of the forecast dry weather.

The department said the rainfall outlook could also affect water levels in hydro-electric dams, particularly because of expected conditions in major water catchment areas.

"The water catchment areas in Mt. Elgon and Mau Escarpment are expected to receive below average rainfall while those over Mt. Kenya are expected to experience mainly dry weather conditions. This may adversely affect water levels in hydro-electric dams," the forecast indicated.

This comes days after Kenya Met predicted rainfall across 9 counties this week.

In a weather forecast on Tuesday, September 1, the authority announced that rainfall is expected in Nairobi, Kiambu, Nyandarua, Meru, Nyeri, Murang’a, Laikipia, Nakuru and Kilifi Counties. 

However, the weatherman noted that most parts of the country will remain dry during the period. 

"Most parts of the country are expected to be generally dry. However, some parts of Nairobi, Kiambu, Nyandarua, Meru, Nyeri, Murang’a, Laikipia, Nakuru and Kilifi Counties are likely to receive rainfall," read the forecast in part. 

The authority also predicted occasional cool and cloudy conditions in Embu, Kiambu, Kirinyaga, Laikipia, Meru, Murang'a and Nairobi in the first half of the forecast period.

Nyandarua, Nyeri, Tharaka Nithi, Nakuru, Machakos, Kajiado and Taita Taveta Counties will also experience the conditions.

The weatherman further predicted high daytime temperatures exceeding 30°C in Kilifi, Tana River, Lamu, Garissa, Wajir, Isiolo, Marsabit, Kakamega, Bungoma, Busia and Turkana counties. 

On the other hand, Meru, Tharaka Nithi, Kirinyaga, Murang’a, Embu, Nyeri, Nyandarua, Laikipia, Nakuru and Narok Counties will experience cold nights, with minimum average temperatures falling below 10°C.