POLITICS

SA rainfall in 2015 the lowest on record - SAWS

Weather Service says 403mm total last year way below the annual average of 608mm

2015 was indeed a very dry year in South Africa

The South African Weather Service has compiled a dataset of monthly average rainfall per province for all 9 provinces dating back to 1904. This dataset was used to calculate the annual total rainfall (Jan – Dec) for South Africa over the 112-year period from 1904 to 2015. The data was analysed and revealed very interesting information.

The annual average rainfall for South Africa, calculated over the full 112 years, is 608 mm.

Over the full 112-year period, the lowest annual total rainfall for South Africa was indeed for the period Jan – Dec 2015 with an annual total of only 403 mm. Following in the table below are the 13 years when the annual total rainfall for South Africa was less than 500 mm.

YEAR

Annual Total Rain (mm)

2015

403

1945

437

1992

440

2003

446

1935

451

1919

451

1965

452

1926

468

1916

476

1927

488

1912

493

1982

496

1941

496

The longest period of consecutive years where the annual total rainfall was below the period average of 608 mm per annum, was the 6 years starting in 1944. If an annual average is calculated for this 6-year period, it is 544 mm.

YEAR

Annual Total Rain (mm)

1944

582

1945

437

1946

569

1947

573

1948

548

1949

555

Average for 6 years

544

The next longest period where the annual total rainfall was below the period average of 608 mm per annum, were 2 periods of 4 consecutive years each.

The first period started in 1930 and the second period started in 2012.

YEAR

Annual Total Rain (mm)

1930

514

1931

548

1932

510

1933

505

Average for 4 years

519

*** 

YEAR

Annual Total Rain (mm)

2012

601

2013

591

2014

581

2015

403

Average for 4 years

544

 The annual average rainfall per annum for the 4 years 1930 – 1933 is 519 mm. The annual average rainfall per annum for the 4 years 2012 – 2015 is 544 mm.

Although the annual total rainfall for South Africa for the 12 months Jan – Dec 2015, was the lowest annual total since 1904, the 4-year period 1930 – 1933 might still be the driest continuous period experienced in South Africa.

Statement issued by Elsa de Jager, Unit Manager: Climate Information, South African Weather Service, 13 January 2016