Grootmodderfontein Weather Records (SF002243890)

Record envelope, standing records and threshold days for Grootmodderfontein (SF002243890), South Africa, with 71 years of record.

Key Facts for Grootmodderfontein

Grootmodderfontein (SF002243890) is a weather station in South Africa at -29.97 latitude and 22.72 longitude, 1,067 m (3,501 ft) above sea level.
The station reports from 1927 to 1997, 71 years of record.
0 records set at Grootmodderfontein still stand.
Records are tracked for prcp: an element needs 30 years of data to be eligible.
Grootmodderfontein set a daily record precipitation of 8.0 mm (0.31 in) on 28 June 1997.

About the Station

Location: South Africa, -29.97 latitude, 22.72 longitude.
Elevation: 1,067 m (3,501 ft).
Period of record: 1927 to 1997, 71 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 Grootmodderfontein. 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 Grootmodderfontein, 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 Grootmodderfontein still stand.

All-Time Record Progression

1 new records

1 all-time records were set at Grootmodderfontein between 30 November 1977 and 30 November 1977. Each dot is a new record.

Wettest Day of Each Month

Nov: 100.0 mm (3.9 in)

The wettest day on record for each calendar month at Grootmodderfontein. The most was 100.0 mm (3.9 in) on 30 November 1977.

Record daily precipitation for each month at Grootmodderfontein
Month	Record daily precipitation (mm)	Date
Jan	61.2 mm (2.4 in)	18 January 1929
Feb	69.0 mm (2.7 in)	20 February 1993
Mar	85.3 mm (3.4 in)	12 March 1948
Apr	40.0 mm (1.6 in)	17 April 1967
May	31.0 mm (1.2 in)	7 May 1976
Jun	31.0 mm (1.2 in)	27 June 1990
Jul	38.1 mm (1.5 in)	12 July 1945
Aug	44.0 mm (1.7 in)	27 August 1992
Sep	36.5 mm (1.4 in)	6 September 1987
Oct	36.1 mm (1.4 in)	10 October 1934
Nov	100.0 mm (3.9 in)	30 November 1977
Dec	37.5 mm (1.5 in)	26 December 1958

Latest Records

Latest records at Grootmodderfontein
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
28 June 1997	Grootmodderfontein, ZA	daily rain	8.0 mm (0.31 in)	8.0 mm (0.31 in)	70 years	20 of 100 (Routine)
11 June 1997	Grootmodderfontein, ZA	daily rain	10.0 mm (0.4 in)	6.0 mm (0.24 in)	4 years	17 of 100 (Routine)
8 June 1997	Grootmodderfontein, ZA	daily rain	2.0 mm (0.08 in)	2.0 mm (0.08 in)	70 years	20 of 100 (Routine)
26 May 1997	Grootmodderfontein, ZA	daily rain	6.5 mm (0.26 in)	6.5 mm (0.26 in)	68 years	20 of 100 (Routine)
6 May 1997	Grootmodderfontein, ZA	daily rain	13.0 mm (0.5 in)	13.0 mm (0.5 in)	68 years	20 of 100 (Routine)
28 March 1997	Grootmodderfontein, ZA	daily rain (Tie)	20.0 mm (0.8 in)	tie	32 years	4 of 100 (Routine)
17 March 1997	Grootmodderfontein, ZA	daily rain	50.0 mm (2.0 in)	27.0 mm (1.1 in)	36 years	39 of 100 (Notable)
16 March 1997	Grootmodderfontein, ZA	daily rain	16.0 mm (0.6 in)	4.0 mm (0.16 in)	23 years	16 of 100 (Routine)
24 July 1996	Grootmodderfontein, ZA	daily rain	8.0 mm (0.31 in)	6.2 mm (0.24 in)	69 years	20 of 100 (Routine)
23 July 1996	Grootmodderfontein, ZA	daily rain	20.0 mm (0.8 in)	20.0 mm (0.8 in)	69 years	20 of 100 (Routine)
22 January 1996	Grootmodderfontein, ZA	daily rain	11.0 mm (0.4 in)	7.0 mm (0.28 in)	21 years	18 of 100 (Routine)
16 December 1995	Grootmodderfontein, ZA	daily rain	19.5 mm (0.8 in)	12.6 mm (0.5 in)	65 years	20 of 100 (Routine)
4 December 1995	Grootmodderfontein, ZA	daily rain	17.5 mm (0.7 in)	5.5 mm (0.22 in)	9 years	14 of 100 (Routine)
22 November 1995	Grootmodderfontein, ZA	daily rain	20.5 mm (0.8 in)	13.9 mm (0.5 in)	48 years	20 of 100 (Routine)
18 November 1995	Grootmodderfontein, ZA	daily rain	19.0 mm (0.7 in)	11.0 mm (0.4 in)	6 years	15 of 100 (Routine)
20 September 1995	Grootmodderfontein, ZA	daily rain	2.0 mm (0.08 in)	2.0 mm (0.08 in)	68 years	20 of 100 (Routine)
3 November 1994	Grootmodderfontein, ZA	daily rain	28.0 mm (1.1 in)	4.5 mm (0.18 in)	11 years	12 of 100 (Routine)
13 February 1994	Grootmodderfontein, ZA	daily rain	45.5 mm (1.8 in)	12.5 mm (0.5 in)	36 years	27 of 100 (Routine)
10 February 1994	Grootmodderfontein, ZA	daily rain	12.0 mm (0.5 in)	3.0 mm (0.12 in)	3 years	8 of 100 (Routine)
12 January 1994	Grootmodderfontein, ZA	daily rain	12.0 mm (0.5 in)	1.9 mm (0.07 in)	36 years	17 of 100 (Routine)

Extremes by Year

1927 to 1997

Yearly extremes at Grootmodderfontein: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Wettest day (Rx1day)	100.0 mm (3.9 in)	1977	34.0 mm (1.3 in)	71
Wettest five days (Rx5day)	117.7 mm (4.6 in)	1954	47.0 mm (1.9 in)	71
Longest dry spell (CDD)	233 days	1937	118 days	71

Wettest day (Rx1day)

The wettest day of the year at Grootmodderfontein, 1927 to 1997. The record is 100.0 mm (3.9 in) in 1977, marked on the chart; the median year is 34.0 mm (1.3 in).

Wettest day (Rx1day) at Grootmodderfontein by year
Year	Wettest day (Rx1day)
1927	10.4 mm (0.4 in)
1928	27.9 mm (1.1 in)
1929	61.2 mm (2.4 in)
1930	19.6 mm (0.8 in)
1931	50.8 mm (2.0 in)
1932	27.9 mm (1.1 in)
1933	23.9 mm (0.9 in)
1934	45.0 mm (1.8 in)
1935	34.0 mm (1.3 in)
1936	20.3 mm (0.8 in)
1937	20.3 mm (0.8 in)
1938	50.8 mm (2.0 in)
1939	30.5 mm (1.2 in)
1940	26.7 mm (1.1 in)
1941	58.4 mm (2.3 in)
1942	26.7 mm (1.1 in)
1943	35.6 mm (1.4 in)
1944	25.4 mm (1.0 in)
1945	41.1 mm (1.6 in)
1946	20.3 mm (0.8 in)
1947	22.9 mm (0.9 in)
1948	85.3 mm (3.4 in)
1949	25.7 mm (1.0 in)
1950	38.1 mm (1.5 in)
1951	29.2 mm (1.1 in)
1952	30.2 mm (1.2 in)
1953	42.5 mm (1.7 in)
1954	50.5 mm (2.0 in)
1955	30.1 mm (1.2 in)
1956	30.5 mm (1.2 in)
1957	33.0 mm (1.3 in)
1958	43.0 mm (1.7 in)
1959	16.0 mm (0.6 in)
1960	43.0 mm (1.7 in)
1961	25.0 mm (1.0 in)
1962	26.2 mm (1.0 in)
1963	55.0 mm (2.2 in)
1964	31.0 mm (1.2 in)
1965	28.0 mm (1.1 in)
1966	47.0 mm (1.9 in)
1967	40.0 mm (1.6 in)
1968	38.0 mm (1.5 in)
1969	35.5 mm (1.4 in)
1970	34.0 mm (1.3 in)
1971	25.5 mm (1.0 in)
1972	49.0 mm (1.9 in)
1973	55.0 mm (2.2 in)
1974	57.5 mm (2.3 in)
1975	47.0 mm (1.9 in)
1976	44.0 mm (1.7 in)
1977	100.0 mm (3.9 in)
1978	61.0 mm (2.4 in)
1979	26.0 mm (1.0 in)
1980	17.0 mm (0.7 in)
1981	38.0 mm (1.5 in)
1982	29.0 mm (1.1 in)
1983	57.0 mm (2.2 in)
1984	24.0 mm (0.9 in)
1985	62.0 mm (2.4 in)
1986	29.0 mm (1.1 in)
1987	37.0 mm (1.5 in)
1988	27.5 mm (1.1 in)
1989	56.5 mm (2.2 in)
1990	31.0 mm (1.2 in)
1991	30.5 mm (1.2 in)
1992	44.0 mm (1.7 in)
1993	69.0 mm (2.7 in)
1994	45.5 mm (1.8 in)
1995	25.5 mm (1.0 in)
1996	20.0 mm (0.8 in)
1997	50.0 mm (2.0 in)

Wettest five days (Rx5day)

The wettest five days of the year at Grootmodderfontein, 1927 to 1997. The record is 117.7 mm (4.6 in) in 1954, marked on the chart; the median year is 47.0 mm (1.9 in).

Wettest five days (Rx5day) at Grootmodderfontein by year
Year	Wettest five days (Rx5day)
1927	10.4 mm (0.4 in)
1928	38.3 mm (1.5 in)
1929	61.2 mm (2.4 in)
1930	19.6 mm (0.8 in)
1931	60.5 mm (2.4 in)
1932	37.8 mm (1.5 in)
1933	42.6 mm (1.7 in)
1934	45.0 mm (1.8 in)
1935	34.0 mm (1.3 in)
1936	26.9 mm (1.1 in)
1937	28.2 mm (1.1 in)
1938	109.2 mm (4.3 in)
1939	67.0 mm (2.6 in)
1940	32.0 mm (1.3 in)
1941	96.5 mm (3.8 in)
1942	35.1 mm (1.4 in)
1943	40.9 mm (1.6 in)
1944	25.4 mm (1.0 in)
1945	48.7 mm (1.9 in)
1946	38.1 mm (1.5 in)
1947	22.9 mm (0.9 in)
1948	85.3 mm (3.4 in)
1949	25.7 mm (1.0 in)
1950	54.1 mm (2.1 in)
1951	29.2 mm (1.1 in)
1952	48.6 mm (1.9 in)
1953	60.5 mm (2.4 in)
1954	117.7 mm (4.6 in)
1955	32.5 mm (1.3 in)
1956	47.2 mm (1.9 in)
1957	49.2 mm (1.9 in)
1958	59.4 mm (2.3 in)
1959	31.0 mm (1.2 in)
1960	49.0 mm (1.9 in)
1961	32.7 mm (1.3 in)
1962	26.5 mm (1.0 in)
1963	60.5 mm (2.4 in)
1964	41.6 mm (1.6 in)
1965	37.5 mm (1.5 in)
1966	47.0 mm (1.9 in)
1967	72.5 mm (2.9 in)
1968	58.5 mm (2.3 in)
1969	65.6 mm (2.6 in)
1970	34.0 mm (1.3 in)
1971	42.5 mm (1.7 in)
1972	77.0 mm (3.0 in)
1973	55.0 mm (2.2 in)
1974	114.0 mm (4.5 in)
1975	62.0 mm (2.4 in)
1976	67.0 mm (2.6 in)
1977	106.5 mm (4.2 in)
1978	61.0 mm (2.4 in)
1979	50.5 mm (2.0 in)
1980	25.0 mm (1.0 in)
1981	38.0 mm (1.5 in)
1982	32.0 mm (1.3 in)
1983	59.0 mm (2.3 in)
1984	24.0 mm (0.9 in)
1985	73.5 mm (2.9 in)
1986	46.0 mm (1.8 in)
1987	40.5 mm (1.6 in)
1988	50.5 mm (2.0 in)
1989	75.0 mm (3.0 in)
1990	41.0 mm (1.6 in)
1991	41.5 mm (1.6 in)
1992	44.0 mm (1.7 in)
1993	69.0 mm (2.7 in)
1994	64.0 mm (2.5 in)
1995	58.0 mm (2.3 in)
1996	30.5 mm (1.2 in)
1997	86.0 mm (3.4 in)

Longest dry spell (CDD)

The longest dry spell of the year at Grootmodderfontein, 1927 to 1997. The record is 233 days in 1937, marked on the chart; the median year is 118 days.

Longest dry spell (CDD) at Grootmodderfontein by year
Year	Longest dry spell (CDD)
1927	128 days
1928	126 days
1929	63 days
1930	137 days
1931	81 days
1932	108 days
1933	77 days
1934	171 days
1935	82 days
1936	116 days
1937	233 days
1938	111 days
1939	136 days
1940	99 days
1941	28 days
1942	214 days
1943	130 days
1944	224 days
1945	172 days
1946	87 days
1947	80 days
1948	173 days
1949	104 days
1950	107 days
1951	134 days
1952	116 days
1953	152 days
1954	141 days
1955	118 days
1956	119 days
1957	85 days
1958	148 days
1959	207 days
1960	134 days
1961	67 days
1962	158 days
1963	103 days
1964	122 days
1965	120 days
1966	130 days
1967	77 days
1968	145 days
1969	139 days
1970	146 days
1971	74 days
1972	144 days
1973	106 days
1974	83 days
1975	141 days
1976	118 days
1977	111 days
1978	127 days
1979	105 days
1980	61 days
1981	152 days
1982	77 days
1983	84 days
1984	121 days
1985	64 days
1986	69 days
1987	68 days
1988	89 days
1989	130 days
1990	149 days
1991	90 days
1992	54 days
1993	78 days
1994	127 days
1995	111 days
1996	96 days
1997	155 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

67 years, 1929 to 1997

A day with at least 35.1 mm (1.4 in) of rain is expected about once in 2 years. A day with at least 95.3 mm (3.8 in) of rain is expected about once in 100 years.

Rainfall return levels at Grootmodderfontein: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	35.1 mm (1.4 in)
5 years	48.8 mm (1.9 in)
10 years	58.8 mm (2.3 in)
25 years	72.5 mm (2.9 in)
50 years	83.5 mm (3.3 in)
100 years	95.3 mm (3.8 in)	Longer than the 67 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, 67 years of values from 1929 to 1997.

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: 100.0 mm (3.9 in) in 1977; 85.3 mm (3.4 in) in 1948; 69.0 mm (2.7 in) in 1993.

Download the Data

Data for Grootmodderfontein standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Grootmodderfontein 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 2026-10-13 (13 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