North Eastern, Coast regions put on high alert as October rains loom

A driver attempts to navigate his vehicle through a flooded road. [File, Standard]

North Eastern and Coast regions have been put on high alert as Kenya braces for above-average October rains, with Mandera, Wajir, Garissa, Tana River, Mombasa, Kilifi, Lamu and Kwale among areas forecast to receive enhanced rainfall.

The Kenya Meteorological Service Authority (KMSA) says Kwale, Mombasa, Kilifi, Lamu, and Mandera have the highest probabilities of receiving above-average rainfall this month, while parts of Taita Taveta, Tana River, Garissa and Wajir have also been placed in the same category.

The warning comes as the country enters the October-December short-rains season, with KMSA forecasting heavy rainfall events in several parts of the country.

The forecast raises concern over flooding and other weather-related hazards in low-lying areas, river basins and settlements with inadequate drainage.

According to KMSA Director General, Edward Muriuki, enhanced rainfall could trigger flash floods, riverine flooding, landslides and localised infrastructure damage, with coastal areas, flood-prone river basins, poorly drained urban centres and steep highland areas particularly vulnerable.

The agency has also warned that the rains could disrupt road transport through flooding, waterlogging and erosion, with rural access roads particularly vulnerable to becoming impassable after sustained rainfall.

In urban centres, drainage systems could be overwhelmed, causing flooding and traffic disruption.

“Rural access roads are particularly vulnerable to becoming impassable after sustained rainfall. Urban areas may also experience traffic disruptions when drainage systems are overwhelmed,” the agency warned.

The forecast places Nairobi among the counties expected to receive above-average rainfall, alongside Kiambu, Murang’a, Nyeri, Nyandarua, Kirinyaga, Embu, Meru, Tharaka-Nithi, Machakos, Kitui, Makueni and Kajiado.

Near-average to above-average rainfall is expected in Baringo, Bomet, Bungoma, Busia, Elgeyo Marakwet, Homa Bay, Kakamega, Kericho, Kisii, Kisumu, Migori, Nandi, Nyamira, Samburu, Siaya, Trans Nzoia, Turkana, Uasin Gishu, Vihiga, West Pokot and parts of Narok, Nakuru and Laikipia Counties.

In Nairobi and several other counties including Nyandarua, Laikipia, Nyeri, Kirinyaga, Murang'a, Kiambu, Meru, Embu, Tharaka-Nithi, Machakos, Kitui, Makueni, Kajiado, Taita-Taveta and inland parts of Tana River, the onset is expected between the second and third weeks of October, with rainfall continuing into January.

In Marsabit, Mandera, Wajir, Garissa and Isiolo, the rains are expected to begin between the first and second weeks of October and continue into the first or second week of December.

Along the Coast, including Mombasa, Kwale, Lamu, Kilifi and the Tana Delta, rainfall has continued from September and is expected to run into the first or second week of December.

KMSA indicated that the rains are expected to bring benefits to agriculture and water resources, improving soil moisture, supporting planting, regenerating pasture and replenishing water sources.

“In arid and semi-arid regions, the rains may contribute significantly to the recovery of water sources that are often stressed during the dry season,” said KMSA n the monthly forecast outlook.

But KMSA cautions that excessive rainfall could result in waterlogging, delayed farm operations, crop diseases and difficulties transporting agricultural produce.

“Heavy rainfall could increase runoff and cause localised flooding in some catchments, especially where drainage systems are inadequate,” Muriuki said.

The El Nino rains is also expected to increase health risks, particularly in areas where drainage and sanitation are poor with KMSA warning that stagnant water could create favourable breeding conditions for mosquitoes and potentially increase transmission of vector-borne diseases such as malaria.

“Low-lying coastal zones, flood-prone river basins, urban centres with poor drainage, and steep highland areas are particularly vulnerable. Flooded or poorly drained settlements may also face higher risks of water-borne diseases where water quality and sanitation are compromised,” Muriuki said.

The October rains are expected to follow a largely dry September when only a few counties, including Bungoma, Mombasa, Busia, Kisii and Kilifi, received rainfall.

Further the agency warned that mean temperatures were warmer than average across the country in September.

Wet conditions are expected to persist beyond October, with the October-December outlook projecting above-average rainfall in dozens of counties.

These include Nairobi, Mombasa, Kilifi, Kwale, Lamu, Garissa, Wajir, Mandera, Tana River, Isiolo, Meru, Embu, Kitui, Makueni, Machakos, Nakuru and Narok.

The wet season will also be accompanied by  warmer-than-average temperatures across the country.

Marsabit, Mandera, Wajir, Garissa and Isiolo could record maximum temperatures of up to 39 degrees Celsius, while Mombasa, Kilifi, Lamu and Kwale could reach 34 degrees Celsius.

Nairobi and neighbouring counties are forecast to record maximum temperatures of between 20 and 32 degrees Celsius.