Koster (Pol) Weather Records (SF005107120)

Record envelope, standing records and threshold days for Koster (Pol) (SF005107120), South Africa, with 87 years of record.

Key Facts for Koster (Pol)

Koster (Pol) (SF005107120) is a weather station in South Africa at -25.87 latitude and 26.90 longitude, 1,553 m (5,095 ft) above sea level.
The station reports from 1911 to 1997, 87 years of record.
0 records set at Koster (Pol) still stand.
Records are tracked for prcp: an element needs 30 years of data to be eligible.
Koster (Pol) set a daily record precipitation of 3.0 mm (0.12 in) on 7 August 1997.

About the Station

Location: South Africa, -25.87 latitude, 26.90 longitude.
Elevation: 1,553 m (5,095 ft).
Period of record: 1911 to 1997, 87 years.
Eligible elements: prcp.

Daily Record Envelope and 2026

0 days at or beyond a record

The band shows the record high and record low for each calendar day at Koster (Pol). The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.

Daily record high and record low at Koster (Pol), with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	n/a	n/a	n/a	n/a
Feb	n/a	n/a	n/a	n/a
Mar	n/a	n/a	n/a	n/a
Apr	n/a	n/a	n/a	n/a
May	n/a	n/a	n/a	n/a
Jun	n/a	n/a	n/a	n/a
Jul	n/a	n/a	n/a	n/a
Aug	n/a	n/a	n/a	n/a
Sep	n/a	n/a	n/a	n/a
Oct	n/a	n/a	n/a	n/a
Nov	n/a	n/a	n/a	n/a
Dec	n/a	n/a	n/a	n/a

Which Years Hold Standing Records

0 standing records

0 records at Koster (Pol) still stand.

All-Time Record Progression

5 new records

5 all-time records were set at Koster (Pol) between 27 October 1943 and 25 January 1981. Each dot is a new record.

When Koster (Pol) set new all-time records
Date	Kind	Detail
1943-10-27	Record daily precipitation	Record daily precipitation 91.9 mm (3.6 in)
1946-12-14	Record daily precipitation	Record daily precipitation 100.6 mm (4.0 in)
1972-02-25	Record daily precipitation	Record daily precipitation 102.0 mm (4.0 in)
1979-03-01	Record daily precipitation	Record daily precipitation 130.0 mm (5.1 in)
1981-01-25	Record daily precipitation	Record daily precipitation 153.5 mm (6.0 in)

Wettest Day of Each Month

Jan: 153.5 mm (6.0 in)

The wettest day on record for each calendar month at Koster (Pol). The most was 153.5 mm (6.0 in) on 25 January 1981.

Record daily precipitation for each month at Koster (Pol)
Month	Record daily precipitation (mm)	Date
Jan	153.5 mm (6.0 in)	25 January 1981
Feb	102.0 mm (4.0 in)	25 February 1972
Mar	130.0 mm (5.1 in)	1 March 1979
Apr	80.5 mm (3.2 in)	25 April 1962
May	60.2 mm (2.4 in)	22 May 1936
Jun	70.0 mm (2.8 in)	11 June 1957
Jul	47.0 mm (1.9 in)	3 July 1957
Aug	48.0 mm (1.9 in)	27 August 1978
Sep	60.1 mm (2.4 in)	25 September 1980
Oct	91.9 mm (3.6 in)	27 October 1943
Nov	72.0 mm (2.8 in)	5 November 1958
Dec	114.5 mm (4.5 in)	17 December 1995

Latest Records

Latest records at Koster (Pol)
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
7 August 1997	Koster (Pol), ZA	daily rain	3.0 mm (0.12 in)	3.0 mm (0.12 in)	84 years	20 of 100 (Routine)
27 July 1997	Koster (Pol), ZA	daily rain	14.5 mm (0.6 in)	12.7 mm (0.5 in)	55 years	20 of 100 (Routine)
27 May 1997	Koster (Pol), ZA	daily rain	24.5 mm (1.0 in)	10.3 mm (0.4 in)	83 years	20 of 100 (Routine)
20 April 1997	Koster (Pol), ZA	daily rain	20.0 mm (0.8 in)	10.5 mm (0.4 in)	36 years	20 of 100 (Routine)
17 April 1996	Koster (Pol), ZA	daily rain	69.2 mm (2.7 in)	24.7 mm (1.0 in)	48 years	41 of 100 (Notable)
12 March 1996	Koster (Pol), ZA	daily rain	40.0 mm (1.6 in)	14.0 mm (0.6 in)	29 years	25 of 100 (Routine)
24 February 1996	Koster (Pol), ZA	daily rain	56.0 mm (2.2 in)	25.0 mm (1.0 in)	40 years	36 of 100 (Notable)
14 February 1996	Koster (Pol), ZA	daily rain	35.0 mm (1.4 in)	7.5 mm (0.30 in)	17 years	18 of 100 (Routine)
13 February 1996	Koster (Pol), ZA	daily rain	46.5 mm (1.8 in)	8.4 mm (0.33 in)	82 years	37 of 100 (Notable)
11 February 1996	Koster (Pol), ZA	daily rain	33.5 mm (1.3 in)	0.4 mm (0.02 in)	5 years	9 of 100 (Routine)
31 January 1996	Koster (Pol), ZA	daily rain	55.0 mm (2.2 in)	15.2 mm (0.6 in)	28 years	27 of 100 (Routine)
26 December 1995	Koster (Pol), ZA	daily rain	45.5 mm (1.8 in)	4.9 mm (0.19 in)	70 years	32 of 100 (Routine)
23 December 1995	Koster (Pol), ZA	daily rain	44.0 mm (1.7 in)	11.0 mm (0.4 in)	48 years	30 of 100 (Routine)
17 December 1995	Koster (Pol), ZA	monthly rain	114.5 mm (4.5 in)	13.9 mm (0.5 in)	49 years	42 of 100 (Notable)
18 November 1995	Koster (Pol), ZA	daily rain	46.0 mm (1.8 in)	16.0 mm (0.6 in)	58 years	38 of 100 (Notable)
16 November 1995	Koster (Pol), ZA	daily rain	54.0 mm (2.1 in)	10.8 mm (0.4 in)	60 years	34 of 100 (Routine)
25 March 1995	Koster (Pol), ZA	daily rain	21.0 mm (0.8 in)	8.6 mm (0.34 in)	58 years	20 of 100 (Routine)
2 February 1995	Koster (Pol), ZA	daily rain	21.5 mm (0.8 in)	3.2 mm (0.13 in)	71 years	20 of 100 (Routine)
25 December 1994	Koster (Pol), ZA	daily rain	46.5 mm (1.8 in)	3.3 mm (0.13 in)	43 years	22 of 100 (Routine)
5 February 1994	Koster (Pol), ZA	daily rain	62.0 mm (2.4 in)	21.3 mm (0.8 in)	4 years	23 of 100 (Routine)

Extremes by Year

1911 to 1997

Yearly extremes at Koster (Pol): the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Wettest day (Rx1day)	153.5 mm (6.0 in)	1981	58.0 mm (2.3 in)	87
Wettest five days (Rx5day)	217.0 mm (8.5 in)	1956	97.0 mm (3.8 in)	87
Longest dry spell (CDD)	272 days	1993	97 days	87

Wettest day (Rx1day)

The wettest day of the year at Koster (Pol), 1911 to 1997. The record is 153.5 mm (6.0 in) in 1981, marked on the chart; the median year is 58.0 mm (2.3 in).

Wettest day (Rx1day) at Koster (Pol) by year
Year	Wettest day (Rx1day)
1911	23.4 mm (0.9 in)
1912	52.6 mm (2.1 in)
1913	62.7 mm (2.5 in)
1914	78.7 mm (3.1 in)
1915	50.0 mm (2.0 in)
1916	41.1 mm (1.6 in)
1917	45.7 mm (1.8 in)
1918	45.2 mm (1.8 in)
1919	30.2 mm (1.2 in)
1920	58.4 mm (2.3 in)
1921	73.7 mm (2.9 in)
1922	34.3 mm (1.4 in)
1923	41.1 mm (1.6 in)
1924	40.6 mm (1.6 in)
1925	43.9 mm (1.7 in)
1926	46.0 mm (1.8 in)
1927	31.0 mm (1.2 in)
1928	54.4 mm (2.1 in)
1929	62.2 mm (2.4 in)
1930	44.7 mm (1.8 in)
1931	58.4 mm (2.3 in)
1932	34.3 mm (1.4 in)
1933	52.1 mm (2.1 in)
1934	58.4 mm (2.3 in)
1935	38.1 mm (1.5 in)
1936	60.2 mm (2.4 in)
1937	33.8 mm (1.3 in)
1938	37.3 mm (1.5 in)
1939	71.1 mm (2.8 in)
1940	68.8 mm (2.7 in)
1941	32.8 mm (1.3 in)
1942	66.0 mm (2.6 in)
1943	91.9 mm (3.6 in)
1944	68.8 mm (2.7 in)
1945	74.4 mm (2.9 in)
1946	100.6 mm (4.0 in)
1947	57.2 mm (2.3 in)
1948	66.8 mm (2.6 in)
1949	51.8 mm (2.0 in)
1950	43.2 mm (1.7 in)
1951	66.0 mm (2.6 in)
1952	63.5 mm (2.5 in)
1953	36.0 mm (1.4 in)
1954	31.0 mm (1.2 in)
1955	58.0 mm (2.3 in)
1956	83.0 mm (3.3 in)
1957	70.0 mm (2.8 in)
1958	80.0 mm (3.1 in)
1959	32.0 mm (1.3 in)
1960	69.0 mm (2.7 in)
1961	41.8 mm (1.6 in)
1962	80.5 mm (3.2 in)
1963	40.5 mm (1.6 in)
1964	32.5 mm (1.3 in)
1965	35.0 mm (1.4 in)
1966	50.0 mm (2.0 in)
1967	53.5 mm (2.1 in)
1968	51.5 mm (2.0 in)
1969	40.0 mm (1.6 in)
1970	78.5 mm (3.1 in)
1971	60.0 mm (2.4 in)
1972	102.0 mm (4.0 in)
1973	60.0 mm (2.4 in)
1974	60.0 mm (2.4 in)
1975	48.0 mm (1.9 in)
1976	64.5 mm (2.5 in)
1977	72.0 mm (2.8 in)
1978	62.4 mm (2.5 in)
1979	130.0 mm (5.1 in)
1980	60.1 mm (2.4 in)
1981	153.5 mm (6.0 in)
1982	43.6 mm (1.7 in)
1983	67.0 mm (2.6 in)
1984	60.0 mm (2.4 in)
1985	39.0 mm (1.5 in)
1986	37.0 mm (1.5 in)
1987	80.5 mm (3.2 in)
1988	68.0 mm (2.7 in)
1989	63.0 mm (2.5 in)
1990	52.2 mm (2.1 in)
1991	56.0 mm (2.2 in)
1992	52.0 mm (2.0 in)
1993	34.0 mm (1.3 in)
1994	62.0 mm (2.4 in)
1995	114.5 mm (4.5 in)
1996	69.2 mm (2.7 in)
1997	66.0 mm (2.6 in)

Wettest five days (Rx5day)

The wettest five days of the year at Koster (Pol), 1911 to 1997. The record is 217.0 mm (8.5 in) in 1956, marked on the chart; the median year is 97.0 mm (3.8 in).

Wettest five days (Rx5day) at Koster (Pol) by year
Year	Wettest five days (Rx5day)
1911	33.5 mm (1.3 in)
1912	69.9 mm (2.8 in)
1913	82.2 mm (3.2 in)
1914	180.8 mm (7.1 in)
1915	117.0 mm (4.6 in)
1916	61.0 mm (2.4 in)
1917	87.1 mm (3.4 in)
1918	74.4 mm (2.9 in)
1919	63.7 mm (2.5 in)
1920	77.5 mm (3.1 in)
1921	185.7 mm (7.3 in)
1922	60.7 mm (2.4 in)
1923	66.6 mm (2.6 in)
1924	93.4 mm (3.7 in)
1925	79.5 mm (3.1 in)
1926	59.0 mm (2.3 in)
1927	67.3 mm (2.6 in)
1928	119.1 mm (4.7 in)
1929	103.6 mm (4.1 in)
1930	63.8 mm (2.5 in)
1931	124.5 mm (4.9 in)
1932	43.1 mm (1.7 in)
1933	76.2 mm (3.0 in)
1934	110.0 mm (4.3 in)
1935	99.3 mm (3.9 in)
1936	118.9 mm (4.7 in)
1937	79.5 mm (3.1 in)
1938	83.1 mm (3.3 in)
1939	144.3 mm (5.7 in)
1940	114.7 mm (4.5 in)
1941	49.0 mm (1.9 in)
1942	121.7 mm (4.8 in)
1943	146.5 mm (5.8 in)
1944	197.3 mm (7.8 in)
1945	163.9 mm (6.5 in)
1946	126.5 mm (5.0 in)
1947	123.7 mm (4.9 in)
1948	107.0 mm (4.2 in)
1949	137.1 mm (5.4 in)
1950	117.0 mm (4.6 in)
1951	83.8 mm (3.3 in)
1952	92.8 mm (3.7 in)
1953	63.5 mm (2.5 in)
1954	66.5 mm (2.6 in)
1955	156.0 mm (6.1 in)
1956	217.0 mm (8.5 in)
1957	97.0 mm (3.8 in)
1958	170.0 mm (6.7 in)
1959	95.0 mm (3.7 in)
1960	160.0 mm (6.3 in)
1961	86.5 mm (3.4 in)
1962	87.5 mm (3.4 in)
1963	68.0 mm (2.7 in)
1964	47.5 mm (1.9 in)
1965	67.0 mm (2.6 in)
1966	116.3 mm (4.6 in)
1967	135.2 mm (5.3 in)
1968	93.0 mm (3.7 in)
1969	65.0 mm (2.6 in)
1970	166.0 mm (6.5 in)
1971	75.0 mm (3.0 in)
1972	201.3 mm (7.9 in)
1973	97.0 mm (3.8 in)
1974	84.5 mm (3.3 in)
1975	120.0 mm (4.7 in)
1976	201.0 mm (7.9 in)
1977	155.0 mm (6.1 in)
1978	118.0 mm (4.6 in)
1979	130.0 mm (5.1 in)
1980	160.7 mm (6.3 in)
1981	185.0 mm (7.3 in)
1982	76.5 mm (3.0 in)
1983	67.0 mm (2.6 in)
1984	91.0 mm (3.6 in)
1985	65.0 mm (2.6 in)
1986	57.0 mm (2.2 in)
1987	102.5 mm (4.0 in)
1988	83.5 mm (3.3 in)
1989	107.7 mm (4.2 in)
1990	73.6 mm (2.9 in)
1991	106.0 mm (4.2 in)
1992	119.0 mm (4.7 in)
1993	69.0 mm (2.7 in)
1994	103.5 mm (4.1 in)
1995	156.1 mm (6.1 in)
1996	137.0 mm (5.4 in)
1997	130.5 mm (5.1 in)

Longest dry spell (CDD)

The longest dry spell of the year at Koster (Pol), 1911 to 1997. The record is 272 days in 1993, marked on the chart; the median year is 97 days.

Longest dry spell (CDD) at Koster (Pol) by year
Year	Longest dry spell (CDD)
1911	21 days
1912	208 days
1913	95 days
1914	71 days
1915	86 days
1916	198 days
1917	56 days
1918	106 days
1919	129 days
1920	167 days
1921	127 days
1922	69 days
1923	39 days
1924	88 days
1925	51 days
1926	69 days
1927	80 days
1928	69 days
1929	52 days
1930	58 days
1931	86 days
1932	109 days
1933	71 days
1934	120 days
1935	47 days
1936	141 days
1937	154 days
1938	105 days
1939	44 days
1940	68 days
1941	168 days
1942	52 days
1943	55 days
1944	94 days
1945	166 days
1946	128 days
1947	138 days
1948	145 days
1949	60 days
1950	108 days
1951	56 days
1952	72 days
1953	143 days
1954	127 days
1955	121 days
1956	110 days
1957	54 days
1958	97 days
1959	86 days
1960	72 days
1961	109 days
1962	158 days
1963	101 days
1964	89 days
1965	90 days
1966	82 days
1967	74 days
1968	102 days
1969	119 days
1970	90 days
1971	76 days
1972	145 days
1973	164 days
1974	130 days
1975	103 days
1976	121 days
1977	109 days
1978	123 days
1979	44 days
1980	124 days
1981	110 days
1982	181 days
1983	56 days
1984	71 days
1985	136 days
1986	85 days
1987	132 days
1988	42 days
1989	51 days
1990	115 days
1991	92 days
1992	133 days
1993	272 days
1994	176 days
1995	128 days
1996	69 days
1997	60 days

Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.

Rainfall Return Levels

78 years, 1912 to 1996

A day with at least 55.8 mm (2.2 in) of rain is expected about once in 2 years. A day with at least 129.7 mm (5.1 in) of rain is expected about once in 100 years.

Rainfall return levels at Koster (Pol): the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	55.8 mm (2.2 in)
5 years	74.5 mm (2.9 in)
10 years	87.3 mm (3.4 in)
25 years	103.9 mm (4.1 in)
50 years	116.7 mm (4.6 in)
100 years	129.7 mm (5.1 in)	Longer than the 78 years of record

The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 78 years of values from 1912 to 1996.

A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.

The largest wettest-day totals in the fit: 153.5 mm (6.0 in) in 1981; 130.0 mm (5.1 in) in 1979; 114.5 mm (4.5 in) in 1995.

Download the Data

Data for Koster (Pol) standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Koster (Pol) threshold days by year: CSV or JSON. Field meanings are on the data page.

Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-14 (14 October 2026). Records are computed by this site and are not official.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).

Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	n/a	n/a	n/a	n/a
Feb	n/a	n/a	n/a	n/a
Mar	n/a	n/a	n/a	n/a
Apr	n/a	n/a	n/a	n/a
May	n/a	n/a	n/a	n/a
Jun	n/a	n/a	n/a	n/a
Jul	n/a	n/a	n/a	n/a
Aug	n/a	n/a	n/a	n/a
Sep	n/a	n/a	n/a	n/a
Oct	n/a	n/a	n/a	n/a
Nov	n/a	n/a	n/a	n/a
Dec	n/a	n/a	n/a	n/a

Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	n/a	n/a	n/a	n/a
Feb	n/a	n/a	n/a	n/a
Mar	n/a	n/a	n/a	n/a
Apr	n/a	n/a	n/a	n/a
May	n/a	n/a	n/a	n/a
Jun	n/a	n/a	n/a	n/a
Jul	n/a	n/a	n/a	n/a
Aug	n/a	n/a	n/a	n/a
Sep	n/a	n/a	n/a	n/a
Oct	n/a	n/a	n/a	n/a
Nov	n/a	n/a	n/a	n/a
Dec	n/a	n/a	n/a	n/a