REPUBLIC OF KENYA
MINISTRY OF ENVIRONMENT, WATER AND NATURAL RESOURCES
STATE DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
KENYA METEOROLOGICAL SERVICE
Dagoretti Corner, Ngong Road, P. O. Box 30259, Nairobi, Kenya,
Telephone: 254-20-3867880-5, Fax: 254-20-3876955/387373,
E-mail:director@meteo.go.ke
REVIEW OF THE WEATHER IN MARCH - APRIL
AND
THE OUTLOOK FOR MAY 2014
Ref N: KMD/FCST/4-2014/MO/05
Issue Date: 30/04/2014
1. SUMMARY
1.1


1.2
Weather Review in March to April 2014
Rainfall analysis from 1st March to 30th April 2014 indicates that the seasonal rainfall was generally
depressed over most parts of the country including the western and central parts of Kenya.
The depressed rainfall recorded over various parts of the country resulted in moisture stress on
crop performance.
The forecast for May 2014
The month of May marks the cessation of the “Long Rains” season over most parts of the country
except the Western highlands, parts of central Rift Valley and the Coastal strip. The outlook for May
2014 indicates that:
 Most areas in the Western highlands (Kitale, Kakamega, Eldoret, Kericho, Kisumu, Kisii),
Central Rift Valley (Narok, Nakuru, Nyahururu, Kajiado), Central highlands including Nairobi
area (Embu, Nyeri, Meru, Murang’a, Dagoretti, Wilson, Thika, Kabete) and the Coastal strip
(Mombasa, Mtwapa, Kilifi, Malindi, Msabaha, Lamu) are likely to receive near normal rainfall
with a tendency to above normal in isolated places.
 The Northwestern Kenya (Lodwar, Lokichoggio, Lokitaung), the northern parts of Kenya
(Marsabit, Moyale), most parts of Northeastern Kenya (Mandera, Wajir, Garissa) and
Southeastern Kenya (Machakos, Kangundo, Makindu, Voi, Taveta etc) are likely to receive near
normal rainfall tending to below normal (generally depressed rainfall).
 The seasonal rainfall is expected to continue into June over the western and Coastal regions. It is
however likely to cease between the third and fourth week of May over the central region and first
and second week of May over most of the North-western, North-eastern and South-eastern
regions. .
2. REVIEW OF RAINFALL PERFORMANCE
2.1 REVIEW OF RAINFALL PERFORMANCE DURING APRIL 2014
During April 2014, highly depressed rainfall was recorded over most parts of the country including
the western and central highlands. Most meteorological stations in the country recorded rainfall that
was well below 75 percent of their Long-Term Means (LTMs) for the month. Stations like Marsabit,
Eldoret, Narok, Malindi, Msabaha and Mombasa recorded less than 20 percent of their April LTMs
while several other stations recorded below 50 percent of their April LTMs. Indeed, Garissa, Wajir,
Nyeri and Meru were the only stations in the country that recorded near-normal rainfall (more than
75 percent of their LTMs).
The most depressed rainfall of just 6 percent of the LTM was recorded at Msabaha while Malindi and
Narok recorded just 8 percent of their LTMs. The rainfall distribution in most parts of the country
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was very poor, both in time and space.
Tuthu rainfall station recorded the highest monthly rainfall total of 306.7mm. This was followed by
Meru Meteorological station 260.0 (107%) as compared to its April LTM of 243.9mm. Butere, Nyeri,
Kakamega, Embu, Mtwapa Kisii, Kericho and Moyale stations recorded 226.3mm (79%), 173.6
(102%), 172.5 (67%), 154.5 (54%), 150.5 (63%), 139.2 (54%), 113.6 (48%) and 105.5mm (57%)
respectively. Thika, Nakuru, Wajir, Kitale, Garissa and Wilson Airport stations recorded between 70
and 100mm while the rest of the stations recorded less than 70mm. The rainfall performance during
April 2014 is shown in Figure 1.
There are some locations that experienced intense rainfall events resulting in very heavy daily
rainfall amounts exceeding 50mm in a day. These stations, the daily rainfall amounts and the dates
are shown in Table 1 below.
Table 1: Stations that recorded very heavy rainfall (≥ 50mm / 24 hrs) in April 2014
NO STATION
AMOUNT DATE
NO STATION
NAME
(mm)
NAME
1
Kakamega
50.9
02.04.2014
5
Nyeri
2
Moyale
53.6
06.04.2014
6
Meru
3
Kerugoya
109.1
13.04.2014
7
Shigharo
4
Wajir
56.4
14.04.2014
2.2
AMOUNT
(mm)
83.1
100.0
53.8
DATE
14.04.2014
15.04.2014
22.04.2014
MARCH-MAY SEASONAL RAINFALL PERFORMANCE UPTO 30TH APRIL 2014
Analysis of March-May 2014 seasonal rainfall indicates that most meteorological stations in the
country recorded highly depressed seasonal rainfall by 30th April. The Coastal stations of Lamu,
Malindi and Msabaha recorded less than 15 percent of their seasonal LTMs. However, three stations
namely Makindu Machakos and Voi had attained their seasonal LTMs by 30th April. The highest
percentage of 125% was recorded at Makindu meteorological station while Machakos and Voi
recorded 90 and 77 percent of their seasonal LTMs respectively.
In terms of seasonal amounts, Embu station recorded the highest amount of 393.5mm (70%) as
compared to its seasonal LTM of 565.3mm. Kericho, Meru, Kisii, Kakamega, Nyeri and Machakos
stations recorded 364.0 (54%), 338.5 (72%), 318.8 (47%), 274.7 (41%), 269.7 (63%) and 250.8 mm
(90%) respectively. The rest of the station recorded less than 250mm (See figure 2).
3.
SYNOPTIC CONDITIONS IN APRIL 2014
During the month of April, very warm Sea Surface Temperatures (SSTs) prevailed over much of the
southwestern Indian Ocean (Mascarene region) and over the Mozambique Channel. This situation
was very conducive for the formation of Tropical Cyclones (TCs) and deep low pressure systems in
the South-west Indian Ocean basin. For example, a very severe TC named “Hellen” formed in the
Mozambique Channel on 30th March. This diverted all the moisture that was to enter into our
country to the TC region, and hence the depressed rainfall during at the beginning of the month of
April. Deep low pressure systems also developed in the same areas in the month of April and had
the same effect of denying moisture influx and subsequent rainfall formation in the county.
The northern Indian Ocean (adjacent to the Horn of Africa), was characterized by slightly cooler than
average SSTs. Pressures over the Arabian region were therefore slightly stronger than average for
most of the month. The Mascarene region (in the Southwest Indian Ocean) and the St. Helena region
(in the south Atlantic ocean) were characterized by weaker than average pressures. The Zonal (eastwest) arm of the Inter-Tropical Convergence Zone (ITCZ), therefore remained to the south of the
country. This also led to the poor rainfall performance over most of the eastern half of the country.
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The Meridional (North-South) arm of the ITCZ was mainly over Uganda and central Africa. This
resulted in depressed and poorly distributed rainfall over much of the western region.
4.
EXPERIENCED IMPACTS
 The depressed rainfall over most agricultural areas in the country has resulted into poor crop
performance and even crop failure in some regions;
 In the pastoral areas of Rift Valley and parts of northeastern Kenya, pastures for animals
deteriorated as a result of poor rainfall performance in the areas;
 Depressed rainfall in the River catchment areas of western and central highlands may lead to
a decrease in water levels in the Seven-Forks, Turkwel and Sondu Miriu hydroelectric power
generation dams;
5.
MAY 2014 FORECAST
The rainfall forecast for May 2014 is based on regression of sea surface temperatures (SSTs), SST
gradients and the expected evolution of global SST patterns as well as upper air circulations patterns
on Kenyan rainfall. The forecast indicates that several parts of western and central Kenya as well as
the Coastal strip are likely to experience near-average rainfall. A few areas in the western highlands
and the Coastal strip are, however, likely to experience slightly enhanced rainfall. Most parts of
Northwestern Kenya, Northern Kenya (Moyale, Marsabit), Northeastern and Southeastern Kenya are
expected to receive near-normal rainfall with a tendency to below normal (generally depressed
rainfall). The specific outlooks for individual areas are as follows:
Most Counties in Western Province (Kakamega, Bungoma, Vihiga, Busia, etc); Nyanza Province
(Siaya, Kisumu, Kisii, Migori, Nyamira etc); a few Counties in Rift Valley Province (Kericho,
Nandi) and Coast Province (Mombasa, Kilifi, Lamu, Kwale) are likely to receive near-normal
rainfall with a slight tendency to above normal (slightly enhanced rainfall) in May;
Several Counties in Rift Valley (Trans Nzoia, Uasin Gishu, West Pokot Baringo, Nakuru, Kajiado,
etc) and Central Province (Nyandarua, Nyeri, Murang’a, Kiambu, Kirinyaga); Nairobi Provinces
and a few Counties in Eastern Province (Embu, Meru, Tharaka-Nithi) are likely to receive nearnormal rainfall in May;
Some Counties in Northern Rift Valley Province (Turkana, etc) Eastern Province (Marsabit, Isiolo,
Kitui, Machakos, Makueni), Northeastern Province (Garissa, Wajir, Mandera) and parts of the
Coast Province (Tana River, Taita-Taveta) are likely to receive near-normal rainfall tending to
below normal (generally depressed rainfall) in May as depicted in figure 3.
6.
POTENTIAL IMPACTS
 Poor crop performance is expected to continue over most parts of southeastern Kenya. The
situation is, however, likely to improve in the agriculturally high-potential areas of Kitale,
Eldoret, Kakamega, Kericho, Kisii and Nandi Hills areas, where near-average rainfall is
forecasted and also expected to continue into June-July-August period.
 Most of the pastoral areas of Northeastern and Northwestern Kenya are expected to
experience depressed rainfall. Pasture for livestock is, therefore, expected to deteriorate in
Counties like Turkana and Garissa. The problem of water scarcity for livestock is also likely to
arise towards the end of May.
 Cases of lightning strikes are still probable in western Kenya. Contingency measures should
still be put in place to avoid loss of lives and destruction of property.
 The water levels in the Seven-Forks and Turkwel hydro-electric power generation dams are
expected to lower slightly despite the expected near-average rainfall in the catchment areas.
7.
EXPECTED CESSATION OF THE 2014 “LONG RAINS” SEASON
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


Western Kenya regions including parts of central Rift Valley (Nakuru, Nyahururu) and the
Coastal strip are expected to continue receiving rainfall into June.
The southern parts of Central Rift Valley (Narok, Kajiado, Magadi) and the Central regions
including Nairobi are likely to experience cessation of the “Long Rains” during the third to
fourth week of May.
In the Northwestern, Northeastern and Southeastern parts of the country, the cessation is
likely to occur during the first to second week of May.
NB: This forecast should be used in conjunction with regular updates as well as the daily (24-hr) forecasts issued by
this Department.
MR. J. G. KONGOTI
DIRECTOR OF METEOROLOGICAL SERVICES & PERMANENT REPRESENTATIVE OF KENYA WITH THE
WORLD METEOROLOGICAL ORGANIZATION (WMO)
FIGURE 1: RAINFALL PERFORMANCE IN APRIL 2014
FIGURE 2: MARCH-MAY SEASONAL RAINFALL
PERFORMANCE UP TO 30TH APRIL 2014
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FIGURE 3: RAINFALL OUTLOOK FOR MAY 2014
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