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
THE OUTLOOK FOR THE JUNE-JULY-AUGUST (JJA) 2014 PERIOD
AND
REVIEW OF RAINFALL DURING THE “LONG RAINS” (MARCH TO MAY) 2014
SEASON
Ref No: KMD/FCST/5-2014/SO/02
1.
Issue Date: 29/05/2014
HIGHLIGHTS
1.1
Outlook for June-July-august (JJA) 2014 season
The climate outlook for June-July-August (JJA) 2014 season indicates that:
 The Western highlands, the Lake Victoria Basin, parts of central Rift Valley (Nakuru, Nyahururu) and the Coastal
strip are likely to receive near-normal rainfall with a tendency towards below normal (depressed rainfall).
 The rest of the country is expected to remain generally dry but relatively cooler as reminiscent of this period of the year.
 Most areas in the Central Highlands and Nairobi area are expected to experience cool and cloudy conditions with
occasional light rains/drizzles.
1.2
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2.
Performance of the March-April-May 2014 “Long Rains” season
The March to May 2014 seasonal rainfall has ceased over most parts of the country except the western, Coastal strip
and some parts of Central highlands.
The rainfall was depressed over most parts of the country, and its distribution, both in time and space, was generally
poor. This was more so over the North West, Nairobi area and parts of central Rift Valley (Narok) where several
meteorological stations recorded less than 50 percent of their seasonal Long-Term Means (LTMs) for March to May
(MAM).
The seasonal rainfall onset was, however, timely over most parts of the country despite the poor distribution.
REVIEW OF MARCH-MAY (LONG-RAINS) 2014 SEASONAL RAINFALL
The March-April-May 2014 seasonal rainfall has ceased over most parts of the country. An assessment
of the rainfall recorded from 1 March to 28 May 2013 (Figures 1a-1d), indicates that the rainfall was
generally depressed over most parts of the country including several parts of Western Kenya and the
Central highlands including Nairobi. Most stations recorded less than 75 percent of their seasonal
Long-Term Means (LTMs) for March to May. The worst conditions were observed over Northwestern,
Nairobi area and parts of central Rift Valley (Narok) where several meteorological stations recorded
less than 50 percent of their LTMs.
The rainfall distribution, both in time and space, was also generally poor over most parts of the
country. The better part of the country, for example, remained generally dry during the peak month
of April 2014 as a result of unanticipated and persistent deep low pressure systems in the
Southwestern Indian Ocean that inhibited moisture flow inland.
Significant amounts of rainfall were, however, recorded over much of the country during the Month
of March. Most stations recorded near-average to above-average rainfall. Makindu station in
Southeastern Kenya, for example, recorded 327 percent of its March LTM. This rainfall also accounted
for 103 percent of the station’s MAM seasonal LTM. Machakos station, also in Southeastern Kenya,
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recorded 254 percent that also accounted for 74 percent of its seasonal LTM.
A slight improvement in rainfall was also realized during the month of May. The most significant
increase was observed along the Coastal strip where heavy rainfall was recorded during the month.
Several rainfall storms (short-lived intense rainfall) were recorded during the season. The heaviest
storm of 119.5mm was recorded at Embu station on 13th March while on the same day, Makindu
station recorded 118.8mm. Other storms of over 100mm recorded during the season include 112.9mm
recorded ar Lamu on 19th May, 110.5mm recorded at Mtwapa station on 5th May, 105.6mm recorded at
Msabaha on 5th May and 100.0mm recorded ar Meru on 15th April 2014.
Up to 28th May, Mtwapa Meteorological station recorded the highest rainfall amount of 692.0mm,
which was 114% of its seasonal LTM. Other stations that recorded rainfall amounts greater than
400mm include; Kericho 595.9mm (88%), Kakamega 497.6mm (73%), Lamu 492.1mm (105%), Kisii
486.6mm (72%), Embu 442.4mm (78%), Malindi 424.6mm (80%) and Msabaha 421.0mm (79%). Nyeri,
Meru, Mombasa, Kisumu, Eldoret and Kitale Stations recorded between 300 and 400mm while the rest
of the stations recorded less than 300mm. The lowest amount of just 31.6mm (33%) was recorded at
Lodwar station in Northwestern Kenya.
3.
EXPERIENCED IMPACTS
The depressed rainfall recorded over much of the country resulted into:
 Poor crop performance over the agricultural areas of the country including the maize-basket
areas of Trans Nzoia, and Uasin Gishu, etc;
 Poor pastures for livestock in the pastoral areas of Kajiado and Narok as well as other areas
within Rift Valley also the northern parts of the country;
 Decrease in water levels in the Seven-Forks as well as Turkwel and Sondu Miriu hydroelectric
power generation dams;
The heavy rainfall recorded in some areas led to:
 Flash floods that destroyed and swept away property in isolated households along the Coastal
strip during the in May; and
 Landslides in Tetu in central Kenya in mid April.
4.
FORECAST FOR JUNE-JULY-AUGUST 2014
In June-July-August (JJA) season, rainfall is normally concentrated over the western region and the
coastal strip. The rest of the country remains generally dry as seen in figure 2.
The climate outlook for June to August 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. Other predictors such as Quasi-Biennial Oscillations (QBO), Southern
Oscillation Index (SOI), and Indian Ocean Dipole (IOD) were also included in the regression. The
expected performance is also based on statistical analysis of past years, whose characteristics were
found to be similar to this year.
The forecast indicates that the Western highlands, the Lake Victoria Basin, parts of central Rift Valley
(Nakuru, Nyahururu) and the Coastal strip are likely to receive near-normal rainfall with a tendency
to below normal (generally depressed rainfall). The rest of the country is expected to remain generally
dry (Figure 3). Most areas in the Central Highlands and Nairobi area are expected to experience cool
and cloudy conditions with occasional drizzles or light rains. The specific outlooks for individual
areas are as follows:
The Western Highlands (Kitale, Kericho, Nandi, Eldoret, Kakamega, Bungoma, Butere/Mumias,
Vihiga etc), Lake Victoria Basin (Kisumu, Nyando, Kisii, Busia), parts Central Rift Valley (Nakuru,
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Ol Kalao, Nyahururu) and the entire Coastal strip (Lamu, Malindi, Msabaha, Mombasa, Kilifi,
Mtwapa)) are likely to receive near-normal rainfall tending to below normal (depressed) rainfall.
The southern parts of Central Rift Valley (Narok, Kajiado) and northwestern regions especially
those bordering Uganda/Sudan (Lokichoggio, Lokitaung etc) are likely to receive Occasional rainfall
(showers and thunderstorms). Long dry spells are, however, likely to dominate.
The Central Highlands (Kiambu, Nyeri, Embu, Meru, Murang’a); Nairobi Area (Dagoretti, Kabete,
Wilson, Jomo Kenyatta International Airport, Eastleigh etc); are likely to experience cool and cloudy
conditions with occasional light rains/drizzles. Occasional prolonged hours of overcast skies (cloudy
conditions) resulting to cold and chilly conditions are expected. The daytime temperatures are,
however, likely to be slightly warmer than average during the period.
Most parts of Northeastern Kenya (Wajir, Mandera, Garissa, Moyale, Marsabit, Isiolo, Garbatulla)
and Southeastern lowlands (Machakos, Makindu, Kitui, Mwingi, Kibwezi, Voi, Taveta) are expected
to remain generally sunny and dry throughout the period. The southeastern regions bordering the
central districts (Machakos area) are likely to experience occasional cool and cloudy conditions with
light rains.
5.
POTENTIAL IMPACTS EXPECTED
The following are the expected impacts during the coming season:
5.1
Agriculture and Food Security Sector
The expected depressed rainfall in western Kenya may lead to low agricultural production over these
areas exacerbated by the poor rainfall performance during the MAM rainfall season. The same
situation is expected in the central highlands and Nairobi area. The expected cloudy conditions and
drizzles/light rains, may, however, reduce evaporation rates and increase soil moisture conditions thus
sustaining favorable cropping conditions in the areas where crops had not withered.
The generally dry weather condition expected elsewhere in the country implies that the crops in these
areas will be adversely affected leading to poor harvest. Food security is therefore expected to
deteriorate over most parts of the country and more so the northern areas of Kenya.
5.2
Disaster Management Sector
In the Arid and Semi-Arid Lands (ASALs), problems related to water scarcity and lack of pasture for
livestock is expected to deteriorate due to the expected sunny and dry conditions in June-July-August
2014. Conflicts over limited resources between Human and wildlife and also between communities
themselves may increase in these areas. Strategies should therefore be put in place to avert such
incidents.
5.3
Health Sector
In areas such as Nairobi, Central highlands, Central Rift Valley and parts of the highlands west of the
Rift Valley, cases of respiratory diseases like asthma, pneumonia and common colds (flu) are
expected to be on the increase due to the expected cool/cold conditions. The general public is advised
to put on warm clothing during this period to minimize chances of being affected. Health authorities
are hence expected to be on the lookout to provide technical advice and also facilitate supply of drugs
necessary to combat these diseases.
Elsewhere, problems related to water scarcity may also increase. This may lead to outbreaks of
diseases like Cholera in those parts of the country where depressed rainfall was recorded during the
MAM season and dry conditions are expected to persist.
5.4
Transport and Public Safety
Flash floods may still occur in Western Kenya and some parts of Central Rift Valley despite the
expected depressed rainfall. This may lead to transport problems, especially in areas where the roads
become impassable when it rains. Slippery roads and poor visibility during foggy conditions may also
pose dangers to motorists and pedestrians, especially along the Kikuyu-Kinungi stretch. All should,
therefore, take utmost care to minimize accidents that would result from such weather conditions.
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Occasionally, thick fog and associated very poor visibility may render landing at Jomo Kenyatta
International Airport (JKIA) impossible. This may lead to diversion of aircrafts to other airports.
5.5
Water Resources Management and the Energy Sectors
The poor performance of the “Long Rains” March-May 2014 led to lower water levels in hydro-electric
power generating dams. The levels are expected to reduce further during the coming three months as
a result of the expected dry weather conditions in the river catchment areas.
The water capacity for domestic use also reduced in most municipalities. This situation is likely to
deteriorate further during the coming three months due to the expected generally dry weather
conditions especially in the marginal areas of the country.
5.6
Environment
The depressed MAM 2014 rainfall over most parts of the country led poor vegetation cover.
The risk for forest fires in the Arid and Semi Arid Lands (ASALs) is quite high due to the expected
sunny and dry conditions leading to dry vegetation combined with relatively strong winds during JuneAugust period.
NB: This outlook should be used with 24 hour forecasts and regular updates on 5-day and monthly and
monthly time scales issued by this Department.
MR. JAMES G. KONGOTI
DIRECTOR OF METEOROLOGICAL SERVICES & PERMANENT REPRESENTATIVE OF KENYA WITH WMO
Figure 1a: % March 2014 Rainfall Performance
Figure 1b: % April 2014 Rainfall Performance
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Figure 1c: % May 2014 Rainfall Performance
Figure 2: Normal JJA Rainfall
Distribution
Figure 1d: % MAM 2014 Rainfall Performance
Figure 3: JJA 2014 Rainfall Outlook
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