$&
EAST
AFRICAN
METEOROLOGICAL
TECHNICAL
MEMORANDUM
DEPARTMENT
No. 17
v t
,S5
RAINFALL
FOR
INTENSITY - DURATION - FREQUENCY
STATIONS
IN
EAST
AFRICA
By
C M . Taylor and E . F . Lawes
-•-
Issued by
E.A. Meteorological Department
E.A. Community
Nairobi
1971
ISEIC LIBRARY
KE - 1971.04
Wageningen
The Netherlands
if
DATA
g
ISRIC LIBRARY
J^F
~T-\oQH
Wageningen, The Netherlands
RAINFALL INTENSITY
-
DURATION
-
FREQUENCY
DATA
FOR
IN EAST AFRICA
SUMMARY
Autographic daily rainfall records for 16 s t a t i o n s in E a s t
twelve y e a r s or more have been a n a l y s e d . Frequency t a b l e s are
short duration, i . e . 15, 30 and 60 minute f a l l s , for 3 hour and 6
daily rainfalls exceeding 25 «nni. A map of E a s t Africa i s given
rainfall to the year 1968.
Africa with a continuous exposure of
presented for high intensity rainfall of
hour amounts exceeding 30 mm, and for
showing the maximum recorded 24 hour
An extreme-value frequency a n a l y s i s h a s been completed for the data extracted using the Gumbel
method, and amounts of rainfall for durations of 15» 30 and 60 minutes, 3 hours and 6 hours, expected to
be equalled or exceeded in various times, i . e . "return p e r i o d s " , are given for periods up to 50 y e a r s .
The theoretical l i n e s are. plotted on Gumbel probability paper for all durations for which sufficient
annual data are a v a i l a b l e .
INTRODUCTION
Engineers require information on the frequency of high intensity rainfall of short durations for
the planning of storm-water drainage s y s t e m s arid flood-control d e s i g n s . Other a p p l i c a t i o n s of t h e s e
data concern problems of soil erosion, irrigation control, road building and air pollution.
The amount of intensity-frequency data available in E a s t Africa h a s hitherto been limited, mainly
for the reason that few meteorological, hydrological or other stations were equipped, with self-recording
raingauges in the earlier days of development, and the difficulty experienced in maintaining reliable
daily records over a long period of time.
For the p u r p o s e s ' o f this study only those s t a t i o n s having a nearly continuous 12 year record,
or greater, up to 1962 i n c l u s i v e have been u s e d . Some of the s t a t i o n s were c l o s e d before 1962, and
the periods of record differ in length and in d a t e . Where records are incomplete for a full year the whole
y e a r ' s record h a s been discarded. It is intended that records from other s t a t i o n s should be a n a l y s e d
in the future, and the r e s u l t s published, a s soon a s p r a c t i c a b l e after the period covered by such records
e x c e e d s twelve y e a r s .
AVAILABLE
RECORDS
Complete daily records for the following 16 s t a t i o n s throughout E a s t Africa h a v e been a n a l y s e d ,
d e t a i l s of the s t a t i o n s and records follow: —
Station
P e r i o d of Record
Equator
1 9 4 1 - 5 9 ( l e s s 1945,50,52)
16
Kabete
1929-55
27
Kisumu
1939-62
24
Kitale
1941-58 ( l e s s 1944)
17
Mombasa Airport
1946-62
17
Nanyüki
1941-62
22
Voi
1 9 4 1 - 6 2 ( l e s s 1944)
21
No. of Y e a r s
KENYA
2W
- 2 Station
Period of Record
No. of Y e a r s
TANZANIA
Dar-es-Salaam:
Kurasini
1942-54")
Airport
1955-62 J
Do dom a
1942-62 (less 1943,45,48-51,55)
14
Kigoma
1939-62
24
'Mbeya
1932-58 (less 1949,50,55)
24
Tabora (Kazeh Hill)
1931-54
24
21
Zanzibar:
Chukwani
1931-511
Airport
1952-62 J
Entebbe
1927-62 (less 196I)
35
Gulu
1947-62 (less 1949,53,55,57)
12
Kampala (Kololo Hill)
1931-54 (less 1951,52)
22
32
T T S~* A ^ T T*X â
UGANDA
TABULATION O F DATA
T a b l e s 1 to 3 s h o w for each station the frequency of occurrence of rainfall of. 15, 30, and 60
minutes duration of intensity greater than 25 mm/hour. T a b l e s 4 and 5 show for 3 hour and 6 hour p e r i o d s
the frequency of occurrence of falls of amount greater than 30 mm. In each table frequencies of amounts
g r e a t e r than certain v a l u e s are listed; t h e intensity (mm/hour) equivalent to an amount (mm) may be
c a l c u l a t e d by dividing the amount by the duration in hours, e.g. a 15-minute amount of 6.2 mm i s
equivalent to an average intensity over t h e 15 minutes of 6.2 •=" % —^- 25 mm/hour. An " o c c u r r e n c e "
m e a n s t h a t i t r a i n e d continuously throughout the period, producing t h e amount indicated in the p a r t i c u l a r
column; thus, i n t e n s e rainfall which i s not continuous for the duration indicated in the table i s not
included, even if the average intensity over the standard time-interval (15 minutes, 30 minutes, e t c . )
falls within the range of the t a b l e . It should b e noted that the 60-minute t a b l e s do not refer to t h e s e t
" c l o c k h o u r s " , but to any period of 60 minutes when continuous rain produced the amount indicated in
the particular column. In the c a s e of the 3 hour and 6 hour periods, the rainfall had to continue throughout
the period and give a total fall g r e a t e r than 30 mm in order to be included. F o r each duration and station
the h i g h e s t recorded amount, together with the corresponding i n t e n s i t y , i s included in each t a b l e . Daily
or 24-hour rainfall frequencies of amounts greater than 25 mm are shown in Table 6; t h e s e refer to t h e
24-hour period ffbm 9 a - m . to 9 a.m., E.A. Standard Time, and are not limited to periods of continuous
rain.
At Figure 1 a map of E a s t Africa i s presented, showing the h i g h e s t daily (24-hour) falls recorded
in any area up to and including 1968; here again the 24-hour period i s from 9 a-m» to 9 a- m « E.A. Standard
Time.
- 3EXTREME VALUE FREQUENCY ANALYSIS
An extreme value frequency a n a l y s i s h a s been carried out for 15, 30 and 60 minutes, and 3 hour
and 6 hour durations, using the annual s e r i e s of maximum values and applying the method of Gumbel.
Figures 2 to 17 contain the theoretical frequency l i n e s resulting from the a n a l y s i s , drawn on
Gumbel probability paper. The a b s c i s s a i s marked out in "return p e r i o d s " . An event which h a s an
n-year return period i s one which will b e equalled or exceeded once every n y e a r s on the average, over
a long period of time. That i s to say, the 20-year rainfall for a given duration and location will be
equalled or exceeded five times in one hundred y e a r s , but not n e c e s s a r i l y at regular i n t e r v a l s of 20 y e a r s .
Two of the events could occur in consecutive y e a r s but, on the average, such events will occur only
five times in 100 y e a r s , or 100 times in 2,000 y e a r s .
The amounts for 2, 5, 10, 20 and 50 year return periods have been read off from the theoretical
l i n e s and are presented at T a b l e s 7 to 9- T h e s e v a l u e s are the most probable i n t e n s i t i e s for the specific
return period and duration.
REFERENCE
Gumbel, E . J . (1954)
:
S t a t i s t i c a l theory of extreme values and some practical a p p l i c a t i o n s , N . B . S . ,
Applied Maths., Series 33-
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-
4-
INDEX TO TABLES AND FIGURES
Page
Table 1 Frequency of occurrence of 15 minute falls greater than 6.2 mm.
5
Table 2 Frequency of occurrence of 30 minute falls greater than 12.5 mm.
6
Table 3 Frequency of occurrence of 60 minute falls greater than 25 mm
7
Table 4 Frequency of occurrence of 3 hour falls greater than 30 mm.
8
Table 5 Frequency of occurrence of 6 hour falls greater than 30 mm.
9
Table 6 Frequency of occurrence of 24 hour totals greater than 25 mm.
10
F i g - . 1 Map of maximum 24-hour rainfall amounts recorded in East Africa
11
F»«-. 2 Extreme value frequency lines — Equator
12
F i g . . 3 Extreme value, frequency lines — Kabete
13
Fig.
14
4 Extreme value frequency lines — Kisumu
F i g . . 5 Extreme value frequency l i n e s — Kitale
15
Fig.
6 Extreme value frequency lines — Mombasa
16
Fig.
7 Extreme value frequency lines — Nanyuki
17
F i g . . 8 Extreme value frequency l i n e s — Voi
18
Fig.
19
9 Extreme value frequency lines — Dar-es-Salaam
Fig. 10 Extreme value frequency lines — Dodoma
20
Fig.
21
H Extreme value frequency l i n e s — Kigoma
Fig. 12 Extreme value frequency lines — Mbeya
22
Fig. 13 Extreme value frequency lines — Tabora
23
Fig. 14 Extreme value frequency l i n e s — Zanzibar
24
Fig. 15 Extreme value frequency lines — Entebbe
25
Fig. 16 Extreme value frequency l i n e s — Gulu
26
Fig..17
Extreme value frequency l i n e s — Kampala
27
Table 7 Amount-duration frequency data, Kenya stations
28
Table 8 Amount-duration frequency data, Tanzania stations
29
Table 9 Amount-duration frequency data, Uganda stations
30
- 5 TABLE
1
Frequency of occurrence of 15-minute cumulative falls greater than 6.2 mm. ;
Frequency of falls greater t h a n : -
6.2
10
15
25
30
35
40
Country
Station
Kenya
Equator
Kabete
Ki sumu
Kitale
Mombasa
Nanyuki
Voi
16
27
24
17
17
22
21
523
1004
1267
721
668
630
379
121
133
630
316
150
131
188
23
28
279
106
38
35
68
5
5
121
36
9
8
18
51
4
3
4
9
21
10
2
2
1
1
Dar-es-Salaam
Do dom a
Kigoma
Mbeya
Tabora
Zanzibar
13
14
24
24
24
32
866
326
939
566
818
1901
315
148
441
152
320
684
102
35
200
25
86
191
34
12
75
6
36
63
9
4
22
2
10
17
2
1
3
1
3
2
1
2
1
2
1
Entebbe
Gulu
Kampala
35
12
22
2079
801
974
922
365
371
324
146
117
116
57
37
45
19
6
15
5
3
7
2
1
Tanzania
Uganda
No. of y e a r s
20
45
mm.
Number of o c c a s i o n s
1
2
2
1
F a l l s of intensity greater
Highest F a l l
than 25 mm/hour
Amount Intensity
Date
Total for period Average per y e a r
mm
mm/hour
Kenya
Jun.53
Apr. 37
Apr. 56
Feb.54
Apr. 53
Equator
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
16
27
24
17
17
22
21
523
1004
1267
721
668
630
379
32.7
40.9
52.8
42.4
39.3
28.6
18é0
24.1
22.0
43.7
29.2
30.0
27.9
40.6
96
88
175
117
120
112
162
Jun.43
J a n . 44
Tanzania
Dar-es-Salaam
Do dom a
Kigoma
Mbeya
Tabora
Zanzibar
13
1'4
24
24
24
32
866
326
939
566
818
1901
66.6
23.3
39.1
23.6
34.1
59.4
35.6
34.5
42.7
38.5
45.2
37.1
142
138
171
154
181
148
Mar. 51
Apr. 56
J a n . 58
Jan.41
Dec.50
Jan.57
Uganda
Entebbe
Gulu
Kampala
35
12
22
2079
801
974
57.7
66.7
44.3
41.1
46.2
37.7
164
185
151
Mar. 52
Feb.60
Aug.45
- 6 TABLE 2
Frequency of occurrence of 30-minute cumulative falls greater than 12.5 nun.
Frequency of falls greater than:—
12.5
15
20
30
35
40
50
55
16
10
6
2
1
4
1
1
3
1
45
Country
Station
Kenya
Equator
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
16
27
24
17
17
22
21
248
334
682
334
304
278
170
72 26
9
5
115 43 21
4
414 260 164 100
198 99 54 30
111 54 21
7
105 49 26 10
119 64 34 16
1
54 33
9
3
4
2
2
6
8
10
Dar-es-Salaam
Dodoma
Kigoma
Mbeya
Tabora
Zanzibar
13
14
24
24
24
32
335
148
420
209
364
747
199
99
296
103
222
500
103 48
48 23
183 111
38 13
115 60
244 107
25
9
52
6
36
51
10
5
24
2
14
28
5
2
9
1
7
12
1
7
1
2
4
Entebbe
Gulu
Kampala
36
12
22
960 665 365 190
336 236 154 75
449 288 159 71
89
39
35
51
20
15
25
7
9
13
6
4
Tanzania
Uganda
No. of years
25
60
65«nm.
Number of occasions
1
1
8
4
1
Falls of intensity greater
Highest Fall
than 25 mm/hour
Amount Intensity Date
Total for period Average per year
mm mm/hour
Kenya
Aug. 55
Jun.56
Apr. J2
May.49
Equator
16
248
15.5
33.0
66
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
27
24
17
17
22
21
334
682
334
304
278
170
12.4
28.4
19.6
17.9
12.6
8.1
36.4
67.3
43.1
56.9
48.0
56.6
73
135
86
114
96
113
Tan:
Dar-es-Salaam
Dodoma
Kigoma
Mbeya
Tabora
Zanzibar
13
14
24
24
24
32
335
148
420
209
364
747
25.8
10.6
17.5
8.7
15.2
23.3
43.8
53.8
55.3
49.1
58.5
50.3
88
108
HI
98
117
101
Feb.32
Apr. 56
Max. 60
Jan.41
Dec.32
Apr. 62
Uganda
Entebbe
Gulu
Kampala
36
12
22
960
336
449
26.7
28.0
20.4
66.5
62.7
56.1
133
125
112
Mar. 52
Feb.60
Aug.45
Jun.43
Apr. 53
Jun.43
Feb.43
- 7 TABLE
3
Frequency of occurrence of 60-minute cumulative falls greater than 25 mm.
Frequency of falls greater than:
25
30
35
40
50
Country
Station
Kenya
Equator
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
16
27
24
17
17
22
21
7
30 14
67 33 18
233 159 113
77 47 31
55 34 19
40 21 13
55 38 22
2
10
3
3
73 47 28
14
7
3
6
4
13
2
4
3
7
8
13
Dar-es-Salaam
Dodoma
Kigoma
Mbeya
Tabora
Zanzibar
13
14
24
24
24
32
86 57
48 33
136 82
31 15
104 73
239 151
38
23
54
9
44
86
25
13
34
7
25
53
13
8
21
4
17
35
Entebbe
Gulu
Kampala
36
12
22
327 199 122
116 69 42
121 75 49
75
19
35
45
12
19
Tanzania
Uganda
N o . of y e a r s
45
55
60
65
70
75
80
85
1
90mm.
Number of o c c a s i o n s
3
17
2
8
5
1
1
1
6
1
5
1
4
4
3
2
5
5
14
1
9
22
3
2
10
1
5
13
1
1
5
1
4
2
1
9
1
7
5
3
1
27
11
14
21
7
6
19
5
3
13
4
2
8
1
1
7
1
4
1
1
F a l l s of intensity g r e a t e r
Highest F a l l
than 25 mm/hour
Amount Intensity
Date
Total for period Average per year
mm
mm/hour
Kenya
Equator
Kabete
Kisumu
16
27
24
30
67
233
1.9
2.5
9.7
41.4
60.0
77.5
Kitale
17
77
4.5
55.9
Mombasa
Nanyuki
Voi
17
22
21
55
40
55
3.2
1.8
2.6
55.0
68.6
108.0
May 53
Apr. 31
J a n . 48
Mar. 41
J u l . 50
Apr. 54
J u l . 47
Feb.43
Tanzania
Dar-es-Salaam
Dodoma
Kigoma
Mbeya
Tabora
Zanzibar
13
14
24
24
24
32
86
48
136
31
104
239
6.6
3.4
5.7
1.3
4.3
7.5
63.8
68.8
75.0
55.3
67.3
81.8
Feb.43
Apr. 56
Apr. 46
Jan.44
Dec.50
Apr. 62
Uganda
Entebbe
Gulu
Kampala
36
12
22
327
116
121
9.1
9.7
5.5
105.4
82.6
71.0
May 58
Aug.47
Dec.43
- 8 TABLE 4
Frequency of occurrence of 3-hour cumulative falls greater than 30 mm.
Frequency of falls greater than:—
30
40
50
Ntumbelr of o c c a s i o n s
Country
Station
Kenya
Equator
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
16
27
24
17
17
22
21
14
67
113
23
74
16
21
8
28
75
16
37
6
17
11
41
6
17
2
13
1
21
1
9
2
7
1
11
4
1
1
4
1
4
3
1
2
1
1
2
1
Dar-es-Salaam
Dodoma
Kigoma
Mbeya
Tabora
Zanzibar
13
14
24
24
24
32
77
44
88
36
92
204
36
27
45
12
41
114
21
14
23
6
19
58
11
5
10
1
5
27
6
3
7
2
5
3
2
1
1
1
14
10
7
6
5
3
1
Entebbe
Qulu
Kampala
36
12
22
239
68
72
129
37
37
67
16
15
39
10
5
24
6
3
11
3
8
3
2
1
1
Tanzania
Uganda
No. of years
Falls of intensity greater
Highest Fall
than 25 mm/hour
Amount Intensity
Date
Total for period Average per year
mm
mm/hour
Kenya
Equator
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
16
27
24
17
17
22
21
14
67
113
23
74
16
21
0.9
2.5
4.7
1.4
4.4
0.7
1.0
48.0
72.3
101.4
65.2
105.0
85.9
106.7
16
24
34
22
35
29
36
Jul. 46
Feb.41
Aug. 44
Mar. 58
Mar. 58
Jul. 47
Nov. 51
Tanzania
Dar-es-Salaam
Dodoma
Kigoma
Mbeya
Tabora
Zanzibar
13
14
24
24
24
32
77
44
88
36
92
204
5.9
3.1
3.7
1.5
3.8
6.4
86.0
73.9
125.9
62.0
78.6
185.4
29
25
42
21
26
62
Feb.43
Jan.60
Oct. 49
F e b . 32
Dec.41
Apr. 62
Uganda
Entebbe
Gulu
Kampala
36
12
22
239
.68
72
6.6
5.7
3.3
260.1
89.9
76.7
87
30
26
May 58
Aug.47
Mar. 40
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ï33B9ig 2 3 n u o E â l l s of i n t e n s i t y g r e a t e r
Highest Fall
ra;n ?S tin tb
t h a n 25 m m / h o u r
Amount I n t e n s i t y
Date
•isy; l o q s g E i e v A Er<öica!lqfaripïei!k>H A v e r a g e p e r y e a r
mm
mm/hour
21
<i.\L
Gu&i.OQ
€3
i>.;
6?8 2
24S
24
24
e I 3231
§2-
o.ess
Ent%tasa
5
26
Voi
Dar-eS'Salaam
DocEwfial
KigomS
Mbeyâ>8
i l
5i£ 3®! 2 2 0 i l 2 € S 9
N any «M I
s.^es
S£
I
M
vt
1
U
20i 13e
à!
318 2
14
3®
9O-160ril lûxb2£gl3O.rl.<&a80j290p;m'Ç.
1
6
1
9
1
138
1
80
Number o l occasions
f
I 21Ç
Dar-eé-Salàam c
Dodoma
Kigoma
Mbeya
Tabora
Z a n z i b a r £•
Entebbe
Gulu
Kampala
3 0 ' 40Ç 5Q& 6 0 ! S 7 0
a n o i a ß N a c hi yreàrs/Vi
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
Tanzania
OOi ? 8
123
Söe
l?i
\S
3^6
4r3
0î8
4£6
Ü2
0.1
€i
3*9
ÜJ9
1&2
ftO
£5
3.8
ö£
£5
OS
1.3
50.8 l o : ) f i "Pl
333dß.H
9 6 . 6 umiiz O J
1 1 5 . 3 9 [ß3ilS
104^edmcKr
117.4ïluyn£20
85-9
ioM
88.1
15
ITIßßIi3S-a3»lEa
128.25mobo21
83.8ßmogiia
138.5 sy9d23
82.3«odßF4
86j6disnߣ4
234.0
3i>
sddsJnd
274.2
ulu86
96.'4U:qmßl ! 6
82.6
14
.
lyhofiS
M a r . 51
Feb.4l
N0V.6I
Mar. 58
Jun.41
J u l . 47
Nov.62
fiinßsnßT
May 46
A p r . 57
Oct. 49
Feb.32
Dec.41
Apr. 62
ßbtißgU
May 58
Aug.48
Feb.37
- 10 TABLE 6
Frequency of occurrence of 24-hour totals greater than 25 mm.
Frequency of totals greater than:—
25
40
55
70
85 100 115 130 145 160 175 230 245 mm.
Number of o c c a s i o n s
Country
Station
Kenya
Equator
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
16
27
24.
17
17
22
21
93 21
241 92
302 132
146 41
Dar-es-Salaam
Do dom a
Kigoma
Mbeya
Ta bora
Zanzibar
13
14
24
24
24
32
233 101 50
89 39 17
234 93 25
119 34 11
216 79 35
497 252 130
23
5
9
2
9
70
15
1
4
2
1
31
Entebbe
Gulu
Kampala
36
12
22
562 199
208 73
214 80
35
11
5
17
3
2
Tanzania
Uganda
No. of years
1
17
1
144 74 43 23 16 11
80 21 4 1 1
83 37 20 12 9 3
33
54
8
90
27
26
1
2
2
1
8
6
3
2
1
1
18
13
7
8
1
1
1
Amounts greater
than 25 mm
Total for period Average per year
1
1
1
1
Highest Fall
Amount
Date
Kenya
Equator
Kabete
Kisumu
Kitale
Mombasa
Nanyuki
Voi
16
27
24
17
17
22
21
93
241
302
146
144
80
83
5.8
8.9
12.6
8.6
8.5
3.6
4.0
52.1
111.3
128.3
104.4
156.0
85.9
119.4
Mar. 51
Feb.41
Nov.61
Mar. 58
May 47
Jul. 47
Feb.43
Tanzania
Dar-es-Salaam
Dodoma
Kigoma
Mbeya
Tabora
Zanzibar
13
14
24
24
24
32
233
89
234
119
216
497
17.9
6.4
9.7
5.0
9.0
15.5
234.2
92.5
138.5
97.5
86.6
247.1
May 46
Apr. 57
Oct. 49
Feb. 32
Dec.41
Apr. 62
Uganda
Entebbe
Gulu
Kampala
36
12
22
562
208
214
15.6
283.0
108.7
90.4
May 58
Aug. 48
Mar. 40
17.3
9.7
11
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- 28 TABLE 7
Amount — Duration — Frequency Data
Kenya
Amounts in millimetres
Duration
Station
Return Period
15 mins.
30 mins.
1 hour
3 hours
6 houi
Equator
2
5
10
20
50
years
years
years
years
years
17
21
24
26
29
24
29
33
37
41
30
36
41
46
52
Kabete
2
5
10
20
50
years
years
years
years
years
15
20
23
26
30
22
29
33
37
43
31
43
52
59
70
41
55
65
74
85
49
65
75
85
98
Kisumu
2
5
10
20
50
years
years
years
years
years
30
36
40
45
50
47
56
63
69
77
51
61
68
74
82
62
77
86
95
107
68
86
98
110
125
Kitale
2
5
10
20
50
years
years
years
years
years
21
27
31
35
39
30
36
40
44
50
41
50
56
61
68
44
54
62
68
77
Mombasa
2
5
10
20
50
years
years
years
years
years
19
2*5
28
31
35
29
40
46
53
61
39
50
57
64
73
56
77
91
104
121
Nanyuki
2
5
10
20
50
years
years
years
years
years
18
22
25
29
31
27
34
39
44
50
34
45
52
60
69
Voi
2
5
10
20
50
years
years
years
years
years
21
27
31
35
40
31
43
51
58
68
42
67
83
99
120
73
99
116
133
155
-
29-
TABLE
8
Amount — Duration — Frequency Data
Amounts in millimetres
Tanzania
Duration
Station
Return Period
15 m i n s .
30 mins.
1 hour
3 hours
6 hours
66
89
104
119
138
Dar-es-Salaam
2
.,
10
20
50
years
years
years
years
years
23
28
32
35
39
35
40
44
47
52
46
54
59
64
72
56
70
80
89
100
Do do m a
2
5
10
20
50
years
years
years
years
years
24
30
34
38
44
31
41
47
53
61
43
55
63
71
81
53
73
86
99
116
Kigoma
2
5
10
20
50
years
years
years
years
years
25
31
35
38
43
36
44
49
54
60
41
54
63
72
82
56
80
95
110
130
Mbeya
2
5
10
20
50
years
years
years
years
years
18
24
28
30
36
25
32
37
42
48
32
42
49
55
64
40
52
60
68
78
Tabora
2
5
10
20
50
years
years
years
years
years
23
31
36
42
48
34
43
50
56
64
42
52
62
69
78
47
60
68
76
87
53
67
76
85
97
Zanzibar
2
5
10
20
50
years
years
years
years
years
23
29
32
35
39
34
41
47
51
58
49
62
71
79
90
68
97
116
135
159
80
118
143
167
199
-i.
TABLE
9
Amount — Duration — Frequency Data
Uganda
Amounts in millimetres
i
I
Duration
Station
Return Period
15 m i n s .
mins.
1 houi
3 hours
6 hours
72
93
106
124
137
Entebbe
2
S
10
20
50
years
years
years
years
years
26
32
36
40
45
38
•18
54
60
69
53
67
76
86
98
69
86
97
108
123
Gulu
2
5
10
20
50
years
years
years
years
years
29
36
41
45
50
43
54
60
67
76
55
70
80
89
101
61
80
92
104
120
Kampala
2
5
10
20
50
years
years
years
years
years
23
29
33
36
41
37
45
51
•S6
63
47
59
66
73
83
53
68
79
89
101
i
4.