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SEASONAL CLIMATE FORECAST INDICATORS
Southern Oscillation Index (SOI)..(ENSO)
SSTS
PRIOR HEATING (e.g. A hot September and October is an indicator for a good summer rainfall season)
WINDS
WESTERLY CLOUD BANDS
TELECONNECTIONS
TRADITIONAL INDICATORS
ENSO vs SPI Scatter plot for Seasons 1950/1951 to 2009/2010
Lanina gfedcb Neutral gfedcb El Nino gfedcb
20
10
20
08
20
06
20
04
20
02
20
00
19
98
19
96
19
94
19
92
19
90
19
88
19
86
19
84
19
82
19
80
19
78
19
76
19
74
19
72
19
70
19
68
19
66
19
64
19
62
19
60
19
58
19
56
19
54
19
52
19
50
SP
I
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
ENSO versus Zimbabwe rainfall
Above Normal
Below Normal Total
El Nino 8 38% 13 62% 21
La Nina 10 67% 5 33% 15
Neutral 13 54% 11 46% 24
60
• Region 1 Harare, much of Mashonaland East, Mashonaland West , Mashonaland Central, northeastern parts of Midlands , parts Manicaland
Below normal rainfall expected
• Region 2 & 3 Region 2 The bulk of
Matabeleland North, parts of Midlands and parts of MashonalandWest.
Region 3 Masvingo, the bulk of Midlands, the extreme southern parts of Manicaland and the bulk of Matabeleland South.
Normal rainfall with a bias towards below normal rainfall is expected
Homogeneous Zones (Oct- December 2015)
• Region 1 & 2Region 1 Harare, much
of Mashonaland East, Mashonaland West , MashonalandCentral, northeasternparts of Midlands , parts Manicaland
Region 2 The bulk of Matabeleland North, parts of Midlands and parts of MashonalandWest.
Normal rainfall with a bias towards below normal rainfall is expected
• Region 3 Masvingo, the bulk of Midlands, the extreme southern parts of Manicalandand the bulk of Matabeleland South.
Normal rainfall with a bias towards above normal rainfall expected
Homogeneous Zones(Nov-Dec 2015-Jan 2016)
Homogeneous Zones(Dec-Feb 2015-Jan 2016)
Region 2The bulk of Matabeleland North, parts of Midlands and parts of MashonalandWest.
• Normal rainfall with a bias towards below normal rainfall is expected
• Region 1 & 3Region 1 Harare, much of
Mashonaland East, Mashonaland West , Mashonaland Central, northeastern parts of Midlands , parts Manicaland
• Region 3 Masvingo, the bulk of Midlands, the extreme southern parts of Manicalandand the bulk of Matabeleland South.
Normal rainfall with a bias towards above normal rainfall expected
• Region 1 MashonalandProvinces, Harare, most of Manicaland, northern parts of Masvingo and northern parts of Midlands.
Normal rainfall with a bias towards above normal rainfall expected
• Regions 2 and 3 Region 2 Most of
Matabeleland North, northwest Matebeleland South, Bulawayo.
Region3 Most of Masvingo, the extreme southern parts of Manicaland, southeast Matebeleland South and the southern parts of Midlands
Normal rainfall with a bias towards below normal rainfall is expected
Homogeneous Zones (Jan- March 2016)
Implications of the forecast for the 2015/16 rainfall season
• There is a high likelihood of a late start to the season for the whole country.
• A short summer rainfall season (December to February) is expected especially over Region 1.
• Hence an option for small grains, short season variety and staggering plants would be encouraged (Agric)
• There is need to enhance rainfall this season as such the national cloud seeding programmeis highly recommended.
• For those with livestock (a)water points should be preserved and
protected and (b) livestock destocking should be given more
consideration and done timeously to avoid losses.
• It is still possible to harvest grass for fodder in those areas where forest fires have not And those with access to dams with water should compliment their farming with irrigation. been lit
Implications cont………
Start of the Season for Zvishavane
Any day after 1 October when an area recieves 20 mm or more of rain in 3 days or less provided there is no dry spell of 10 days or more in the next 30 days
2010
2007
2004
2001
1998
1995
1992
1989
1986
1983
1980
1977
1974
1971
1968
1965
1962
26 Jan
16 Jan
6 Jan
27 Dec
17 Dec
7 Dec
27 Nov
17 Nov
7 Nov
28 Oct
Some Agrometeorological ProductsSeason length for Zvishavane
2010
2007
2004
2001
1998
1995
1992
1989
1986
1983
1980
1977
1974
1971
1968
1965
1962
Da
ys
180
170
160
150
140
130
120
110
100
90
80
70
End of Season for Zvishavane
When water balance is zero or when there is no moisture available to the plant after a place recieves 10 mm or more
2013
2010
2007
2004
2001
1998
1995
1992
1989
1986
1983
1980
1977
1974
1971
1968
1965
1962
5 May
25 Apr
15 Apr
5 Apr
26 Mar
16 Mar
6 Mar
Seasonal total for Zvishavane
2013
2010
2007
2004
2001
1998
1995
1992
1989
1986
1983
1980
1977
1974
1971
1968
1965
1962
Sea
sona
l tot
al (m
m)
900
800
700
600
500
400
300
200