Nairobi residents may have to endure several more days of unusually cold weather after experts linked the current chilly conditions to increased cloud cover caused by a weather system known as the Madden-Julian Oscillation (MJO).
Weather analyst Maithya wa Vilivū explained that the atmospheric phenomenon is strengthening cold conditions across the highlands east and west of the Rift Valley, including Nairobi and parts of the South Eastern region.
According to the analyst, the recent MJO wave moving across Equatorial Africa and the Indian Ocean has increased cloudiness, reducing the amount of sunlight reaching the ground and preventing temperatures from rising during the day.
The Madden-Julian Oscillation is a large-scale tropical weather pattern that travels eastwards around the globe every 30 to 60 days. It influences rainfall, cloud formation and wind patterns across affected regions.
When the MJO passes over Equatorial Africa and the Indian Ocean, it can bring widespread cloud cover that blocks the sun’s warming effect. Combined with cool south-easterly winds, the result is prolonged cold weather, especially in highland areas such as Nairobi.
Maithya noted that Monday and Tuesday are expected to be the coldest days of the week as thick clouds reduce sunshine hours and keep daytime temperatures lower than usual.
However, residents could get temporary relief on Wednesday, when warmer conditions are expected before cooler weather returns on Thursday and Friday. Saturday is forecast to be warmer, although temperatures may drop again on Sunday.
The cold spell comes as the Kenya Meteorological Department’s August weather outlook shows that the country is gradually moving out of the cold season, but several regions will continue experiencing cool and cloudy conditions.
Nairobi, Kiambu, Murang’a, Nyeri, Embu, Meru, Tharaka Nithi, Kirinyaga and Nyandarua are among counties expected to experience intermittent cloudiness, morning drizzle, fog and light rainfall during the month.
In its weekly forecast for August 4 to 10, the meteorological department said most parts of Kenya are expected to remain generally dry, although some areas including Bungoma, Trans Nzoia, Kakamega, Nakuru, Uasin Gishu, Elgeyo Marakwet, Kericho, Nyandarua, Nyeri and Murang’a may receive rainfall.
The forecast indicates that Nairobi and parts of Central Kenya will continue experiencing cool and cloudy weather, with occasional light rains during mornings and afternoons.
Night temperatures are also expected to remain low, with some highland regions recording minimum temperatures below 10 degrees Celsius. Nairobi is projected to experience daytime temperatures of around 27 degrees Celsius and nighttime lows of approximately 11 degrees Celsius.
Kenya Met has also warned of strong south-easterly winds affecting parts of northern, coastal and eastern Kenya, which could disrupt transport, damage light structures and worsen the cold conditions in some areas.
As the cold weather persists, residents in Nairobi and other highland regions are advised to prepare for chilly mornings, cloudy afternoons and colder nights in the coming days.