Historic Rainfall

The graph above shows the rainfall for Stellenbosch from 1880 to 2017. The data for 1880 tot 1985 was obtained from the Global Historical Climatology Network (GHCN). It is unclear exactly where and how the rainfall was collected. The coordinates are given as 33.93º S 18.87º E. The rainfall data from 2005 to 2017 is from the La Colline Observatory weather station. Although one generally cannot just splice together the data from two different places, the two places are 1 km from each other so it probably would not make much difference over the course of a year. From the graph it is clear that the rainfall pattern has not changed.

In the year 2000 Stellenbosch had the most rain in 50 years so it exceeded the 1053 mm of 1977.

The average over the 1880 to 1985 period was 713 mm and the average over the 2005 to 2017 period was 693 mm. So the average is basically the same.

Driest years

Rank	Year	Total (mm)
1	1928	301.4
2	2015	385.1
3	1905	394.3
4	2017	468.8
5	1971	506.7
6	1919	510.6

Wettest years

Rank	Year	Total (mm)
1	1902	1098.1
2	1941	1063.1
3	2000	> 1053
4	1977	1052.9
5	1962	1016.0
6	2013	993.9

The data from 1880 to 1985 is unfortunately not complete. Quite a number of years has months with missing data and was not included in the graph. The years with missing months are as follows (year, rainfall total, missing months): 1879 536.4 (2, 3, 4), 1881 639.2 (2), 1882 523.7 (6), 1883 645.4 (9), 1884 297.1 (5, 6, 7), 1885 (7), 1892 724.0 (2, 9), 1896 449.2 (7), 1925 665.1 (10), 1927 521.1 (7), 1930 492.0 (9), 1931 495.0 (4, 5), 1954 696.0 (7), 1970 604.4 (6).

Here is another examination of the long-term rainfall pattern in Cape Town which shows that the current drought is nothing special. It happened before. What do long-term data reveals about Cape Town's water shortage?