•Most people were surprised by the downpours but the Met said it had been predicted.
• The IGAD Climate Prediction Centre at Dagoretti Corner said the weather could encourage the spread of locusts.
No one's happy about these rains except the locusts. They thrive and spread with the downpours.
And there's more to come, both rainfall and locusts.
The IGAD (the Intergovernmental Authority on Development) Climate Prediction Centre in Dagorete said wet weather encourages the spread of locusts.
"Weather and climate conditions have contributed to the worst locust situation in 25 years. It has affected Ethiopia, Somalia, Djibouti, Eritrea, Sudan and Kenya. Risk of spread to South Sudan and Uganda is very high," Igad said.
The Met said most parts of the country will receive rains this week, an unexpected turn from a usually dry start of the month. January is generally dry.
The meteorological department said the rains, which caught many Kenyans by surprise, will be heavier in the southern part of the country.
"Enhanced rainfall is expected over the southwestern region and is likely to spread to the Central, Eastern and Coastal regions," director of the meteorological department Stella Aura said.
In the monthly forecast released two weeks ago, the Met said most parts of the country would be generally dry and sunny. But some regions will experience heavy rains.
Aura said the rainfall in January will be higher than the long-term average amounts received during the same month in other years.
“The beginning of January is likely to be wet with occasional rainfall which is likely to be more frequent in the afternoons and during the night,” she said in a statement.
A few areas in Western Kenya and parts of Central Kenya will experience episodes of heavy rainfall resulting in flooding in the first two weeks of the month.
These areas include Siaya, Kisumu, Homa Bay, Migori, Kisii, Nyamira, Trans Nzoia, Baringo, Uasin Gishu, Elgeyo Marakwet, Nandi, Laikipia, Nakuru, Narok, Kericho, Bomet, Kakamega, Vihiga, Bungoma and Busia counties.
The October-November-December seasonal rainfall onset was early in most parts and the distribution both in time and space, was good throughout the country, the Met said.
It said, "The generally good rainfall performance in the country was mainly a result of the strong positive Indian Ocean Dipole. This is owing to the prevailing warm sea surface temperatures in the western Equatorial Indian Ocean adjacent to the East African Coast and the cool sea surface temperatures in the eastern Equatorial Indian Ocean adjacent to Australia."
Nairobi, Embu, Nyandarua, Nyeri, Kirinyaga, Murang'a, Kiambu, Meru and Tharaka Nithi counties will have occasional light morning rains and afternoon showers over several places in the first two weeks of the month.
(Edited by V. Graham)