NAIROBI – The Kenya Weather Service (KMD) has warned that Kenyans remain vigilant about potentially heavy downpours and take necessary precautions as the long rainy season begins in March to April (MAM).
KMD director David Gikungu confirmed the onset of the disease this week, saying that rain is expected to continue in several parts of the country.
“This week’s forecasts show that rainfall will continue in several parts of the country,” Gikungu said.
He further warned that the segregated heavy rain events are likely areas in the eastern and west highlands of Lift Valley, particularly Nairobi County, the Lake Victoria Basin, Lift Valley, the southeastern lowlands and northeastern Kenya.
Gikungu noted that the rain recorded in the week 3-9 March 2025 showed a significant increase in rainfall, particularly in the lowlands and parts of the northeastern region.
Subsequent rain recorded in the week of March 10th-16th, 2025 marked the official start of the MAM 2025 season, particularly in the Highlands and Lake Victoria basin, west of Lift Valley.
Similar rainfall was experienced in Rift Valley, highlands to the east of Rift Valley, lowlands to the southeast, and in parts of isolated areas of Isiolo County.
“The start of the March-April (MAM) “Long rain” season is specifically defined as the first day of the rainy season when two important conditions are met. It produces a wet spell characterized by at least 20 mm of rainfall over three consecutive days,” KMD explained.
Necessary Threshold
Furthermore, there are no dry spells defined as a period of very little rainfall over the next 21 days, which lasts at least 7 days.
For the northern part of the country, the threshold is slightly lower, with the required accumulated rainfall of at least 10 mm over three days.
Gikungu is expected to experience the start of this week’s season, the rest of the highlands east of Rift Valley and the lowlands in the southeast.
“We are also looking forward to launching the Northeast region this week (March 18-24) and next week (March 25-31), but this could be followed by dry spells,” Gikungu added.
He also revealed that Kenya’s northwestern and coastal areas are expected to experience occasional rainfall for the rest of March 2025.
According to KMD, coastal areas are expected to experience peak seasons in May, with an outbreak likely to occur in April.