Iroquois Weather Records (USC00394254)

Record envelope, standing records and threshold days for Iroquois (USC00394254), South Dakota, United States, with 73 years of record.

Key Facts for Iroquois

Iroquois (USC00394254) is a weather station in South Dakota, United States at 44.36 latitude and -97.85 longitude, 426 m (1,398 ft) above sea level.
The station reports from 1951 to 2023, 73 years of record.
0 records set at Iroquois still stand.
Records are tracked for prcp, snow, snwd: an element needs 30 years of data to be eligible.
Iroquois set a daily record snowfall of 11.4 cm (4.5 in) on 9 March 2023.

About the Station

Location: South Dakota, United States, 44.36 latitude, -97.85 longitude.
Elevation: 426 m (1,398 ft).
Period of record: 1951 to 2023, 73 years.
Eligible elements: prcp, snow, snwd.

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 Iroquois. 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 Iroquois, 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 Iroquois still stand.

All-Time Record Progression

9 new records

9 all-time records were set at Iroquois between 23 January 1982 and 25 February 2001. Each dot is a new record.

When Iroquois set new all-time records
Date	Kind	Detail
1982-01-23	Record snow depth	Record snow depth 58.4 cm (23.0 in)
1982-01-24	Record snow depth	Record snow depth 63.5 cm (25.0 in)
1986-07-25	Record daily precipitation	Record daily precipitation 132.1 mm (5.2 in)
1993-11-25	Record daily snowfall	Record daily snowfall 38.1 cm (15.0 in)
2001-01-30	Record daily snowfall	Record daily snowfall 40.6 cm (16.0 in)
2001-01-30	Record snow depth	Record snow depth 71.1 cm (28.0 in)
2001-02-08	Record snow depth	Record snow depth 78.7 cm (31.0 in)
2001-02-24	Record snow depth	Record snow depth 81.3 cm (32.0 in)
2001-02-25	Record snow depth	Record snow depth 91.4 cm (36.0 in)

Wettest Day of Each Month

Jul: 132.1 mm (5.2 in)

The wettest day on record for each calendar month at Iroquois. The most was 132.1 mm (5.2 in) on 25 July 1986.

Record daily precipitation for each month at Iroquois
Month	Record daily precipitation (mm)	Date
Jan	30.0 mm (1.2 in)	30 January 2001
Feb	31.2 mm (1.2 in)	28 February 2012
Mar	40.6 mm (1.6 in)	27 March 2004
Apr	53.1 mm (2.1 in)	7 April 2001
May	99.1 mm (3.9 in)	24 May 1972
Jun	99.1 mm (3.9 in)	4 June 1991
Jul	132.1 mm (5.2 in)	25 July 1986
Aug	79.2 mm (3.1 in)	5 August 1960
Sep	80.0 mm (3.1 in)	15 September 1997
Oct	59.9 mm (2.4 in)	17 October 1998
Nov	46.0 mm (1.8 in)	1 November 2000
Dec	23.1 mm (0.9 in)	30 December 2006

Latest Records

Latest records at Iroquois
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
9 March 2023	Iroquois, US	daily snowfall	11.4 cm (4.5 in)	2.5 cm (1.0 in)	9 years	13 of 100 (Routine)
23 February 2023	Iroquois, US	daily snowfall (Tie)	15.2 cm (6.0 in)	tie	11 years	2 of 100 (Routine)
3 January 2023	Iroquois, US	daily snowfall	11.4 cm (4.5 in)	2.5 cm (1.0 in)	13 years	16 of 100 (Routine)
15 December 2022	Iroquois, US	daily snowfall	15.7 cm (6.2 in)	6.0 cm (2.4 in)	8 years	21 of 100 (Routine)
14 December 2022	Iroquois, US	daily rain	6.1 mm (0.24 in)	1.8 mm (0.07 in)	48 years	20 of 100 (Routine)
13 December 2022	Iroquois, US	daily rain	11.4 mm (0.4 in)	8.9 mm (0.35 in)	29 years	20 of 100 (Routine)
7 August 2022	Iroquois, US	daily rain	23.1 mm (0.9 in)	8.1 mm (0.32 in)	71 years	20 of 100 (Routine)
30 April 2022	Iroquois, US	daily rain	43.4 mm (1.7 in)	8.6 mm (0.34 in)	31 years	25 of 100 (Routine)
6 December 2021	Iroquois, US	daily snowfall	0.3 cm (0.1 in)	0.3 cm (0.1 in)	68 years	20 of 100 (Routine)
27 October 2021	Iroquois, US	daily rain	36.8 mm (1.4 in)	1.2 mm (0.05 in)	50 years	23 of 100 (Routine)
20 October 2021	Iroquois, US	daily rain	14.7 mm (0.6 in)	1.5 mm (0.06 in)	58 years	20 of 100 (Routine)
13 September 2021	Iroquois, US	daily rain	26.4 mm (1.0 in)	3.8 mm (0.15 in)	36 years	20 of 100 (Routine)
2 September 2021	Iroquois, US	daily rain	62.7 mm (2.5 in)	34.8 mm (1.4 in)	28 years	48 of 100 (Notable)
24 July 2021	Iroquois, US	daily rain	43.7 mm (1.7 in)	6.4 mm (0.25 in)	20 years	17 of 100 (Routine)
14 July 2021	Iroquois, US	daily rain	31.0 mm (1.2 in)	18.3 mm (0.7 in)	36 years	31 of 100 (Routine)
15 March 2021	Iroquois, US	daily rain	8.6 mm (0.34 in)	4.0 mm (0.16 in)	32 years	20 of 100 (Routine)
15 March 2021	Iroquois, US	daily snowfall	8.9 cm (3.5 in)	1.3 cm (0.5 in)	38 years	20 of 100 (Routine)
10 March 2021	Iroquois, US	daily snowfall	14.0 cm (5.5 in)	6.4 cm (2.5 in)	64 years	37 of 100 (Notable)
10 March 2021	Iroquois, US	daily rain	13.0 mm (0.5 in)	2.6 mm (0.10 in)	3 years	11 of 100 (Routine)
23 January 2021	Iroquois, US	daily rain (Tie)	4.6 mm (0.18 in)	tie	11 years	2 of 100 (Routine)

Extremes by Year

1951 to 2023

Yearly extremes at Iroquois: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Wettest day (Rx1day)	132.1 mm (5.2 in)	1986	48.0 mm (1.9 in)	73
Wettest five days (Rx5day)	145.7 mm (5.7 in)	1962	67.3 mm (2.6 in)	73
Longest dry spell (CDD)	68 days	1999	31 days	73

Wettest day (Rx1day)

The wettest day of the year at Iroquois, 1951 to 2023. The record is 132.1 mm (5.2 in) in 1986, marked on the chart; the median year is 48.0 mm (1.9 in).

Wettest day (Rx1day) at Iroquois by year
Year	Wettest day (Rx1day)
1951	51.6 mm (2.0 in)
1952	34.5 mm (1.4 in)
1953	48.3 mm (1.9 in)
1954	41.9 mm (1.6 in)
1955	35.6 mm (1.4 in)
1956	54.6 mm (2.1 in)
1957	37.6 mm (1.5 in)
1958	43.2 mm (1.7 in)
1959	45.2 mm (1.8 in)
1960	79.2 mm (3.1 in)
1961	57.2 mm (2.3 in)
1962	75.4 mm (3.0 in)
1963	64.8 mm (2.6 in)
1964	21.6 mm (0.9 in)
1965	40.1 mm (1.6 in)
1966	52.6 mm (2.1 in)
1967	66.8 mm (2.6 in)
1968	40.9 mm (1.6 in)
1969	35.6 mm (1.4 in)
1970	42.4 mm (1.7 in)
1971	45.7 mm (1.8 in)
1972	99.1 mm (3.9 in)
1973	33.5 mm (1.3 in)
1974	45.7 mm (1.8 in)
1975	24.1 mm (0.9 in)
1976	46.5 mm (1.8 in)
1977	28.2 mm (1.1 in)
1978	28.2 mm (1.1 in)
1979	43.2 mm (1.7 in)
1980	39.6 mm (1.6 in)
1981	54.6 mm (2.1 in)
1982	58.4 mm (2.3 in)
1983	28.7 mm (1.1 in)
1984	50.8 mm (2.0 in)
1985	53.3 mm (2.1 in)
1986	132.1 mm (5.2 in)
1987	53.3 mm (2.1 in)
1988	29.2 mm (1.1 in)
1989	36.6 mm (1.4 in)
1990	48.3 mm (1.9 in)
1991	99.1 mm (3.9 in)
1992	39.4 mm (1.6 in)
1993	30.5 mm (1.2 in)
1994	45.7 mm (1.8 in)
1995	53.3 mm (2.1 in)
1996	40.6 mm (1.6 in)
1997	80.0 mm (3.1 in)
1998	59.9 mm (2.4 in)
1999	44.2 mm (1.7 in)
2000	46.0 mm (1.8 in)
2001	74.7 mm (2.9 in)
2002	33.8 mm (1.3 in)
2003	49.0 mm (1.9 in)
2004	73.2 mm (2.9 in)
2005	68.6 mm (2.7 in)
2006	42.7 mm (1.7 in)
2007	96.8 mm (3.8 in)
2008	30.2 mm (1.2 in)
2009	40.1 mm (1.6 in)
2010	92.7 mm (3.6 in)
2011	68.1 mm (2.7 in)
2012	54.4 mm (2.1 in)
2013	48.0 mm (1.9 in)
2014	57.7 mm (2.3 in)
2015	71.6 mm (2.8 in)
2016	53.3 mm (2.1 in)
2017	62.7 mm (2.5 in)
2018	33.3 mm (1.3 in)
2019	46.2 mm (1.8 in)
2020	71.1 mm (2.8 in)
2021	62.7 mm (2.5 in)
2022	52.3 mm (2.1 in)
2023	33.5 mm (1.3 in)

Wettest five days (Rx5day)

The wettest five days of the year at Iroquois, 1951 to 2023. The record is 145.7 mm (5.7 in) in 1962, marked on the chart; the median year is 67.3 mm (2.6 in).

Wettest five days (Rx5day) at Iroquois by year
Year	Wettest five days (Rx5day)
1951	110.6 mm (4.4 in)
1952	50.7 mm (2.0 in)
1953	62.5 mm (2.5 in)
1954	58.7 mm (2.3 in)
1955	38.6 mm (1.5 in)
1956	122.2 mm (4.8 in)
1957	55.1 mm (2.2 in)
1958	62.8 mm (2.5 in)
1959	45.2 mm (1.8 in)
1960	91.9 mm (3.6 in)
1961	100.7 mm (4.0 in)
1962	145.7 mm (5.7 in)
1963	74.5 mm (2.9 in)
1964	30.5 mm (1.2 in)
1965	90.4 mm (3.6 in)
1966	57.7 mm (2.3 in)
1967	132.4 mm (5.2 in)
1968	81.3 mm (3.2 in)
1969	63.6 mm (2.5 in)
1970	67.1 mm (2.6 in)
1971	66.6 mm (2.6 in)
1972	136.5 mm (5.4 in)
1973	39.6 mm (1.6 in)
1974	46.5 mm (1.8 in)
1975	42.5 mm (1.7 in)
1976	46.5 mm (1.8 in)
1977	50.8 mm (2.0 in)
1978	44.4 mm (1.7 in)
1979	51.1 mm (2.0 in)
1980	62.9 mm (2.5 in)
1981	65.8 mm (2.6 in)
1982	78.8 mm (3.1 in)
1983	57.7 mm (2.3 in)
1984	84.5 mm (3.3 in)
1985	67.3 mm (2.6 in)
1986	139.5 mm (5.5 in)
1987	68.1 mm (2.7 in)
1988	70.1 mm (2.8 in)
1989	54.5 mm (2.1 in)
1990	124.5 mm (4.9 in)
1991	139.8 mm (5.5 in)
1992	42.7 mm (1.7 in)
1993	58.2 mm (2.3 in)
1994	55.0 mm (2.2 in)
1995	73.2 mm (2.9 in)
1996	52.6 mm (2.1 in)
1997	90.9 mm (3.6 in)
1998	124.7 mm (4.9 in)
1999	46.2 mm (1.8 in)
2000	54.8 mm (2.2 in)
2001	99.3 mm (3.9 in)
2002	64.1 mm (2.5 in)
2003	74.4 mm (2.9 in)
2004	86.9 mm (3.4 in)
2005	106.4 mm (4.2 in)
2006	84.9 mm (3.3 in)
2007	116.1 mm (4.6 in)
2008	38.6 mm (1.5 in)
2009	60.7 mm (2.4 in)
2010	123.0 mm (4.8 in)
2011	108.0 mm (4.3 in)
2012	73.1 mm (2.9 in)
2013	68.6 mm (2.7 in)
2014	57.7 mm (2.3 in)
2015	111.7 mm (4.4 in)
2016	106.1 mm (4.2 in)
2017	126.4 mm (5.0 in)
2018	67.2 mm (2.6 in)
2019	113.0 mm (4.4 in)
2020	95.0 mm (3.7 in)
2021	64.5 mm (2.5 in)
2022	54.6 mm (2.1 in)
2023	72.1 mm (2.8 in)

Longest dry spell (CDD)

The longest dry spell of the year at Iroquois, 1951 to 2023. The record is 68 days in 1999, marked on the chart; the median year is 31 days.

Longest dry spell (CDD) at Iroquois by year
Year	Longest dry spell (CDD)
1951	20 days
1952	57 days
1953	30 days
1954	31 days
1955	40 days
1956	39 days
1957	40 days
1958	44 days
1959	39 days
1960	26 days
1961	36 days
1962	47 days
1963	26 days
1964	31 days
1965	24 days
1966	25 days
1967	26 days
1968	67 days
1969	21 days
1970	35 days
1971	34 days
1972	31 days
1973	22 days
1974	31 days
1975	41 days
1976	39 days
1977	25 days
1978	33 days
1979	29 days
1980	30 days
1981	32 days
1982	45 days
1983	59 days
1984	39 days
1985	15 days
1986	44 days
1987	26 days
1988	26 days
1989	33 days
1990	57 days
1991	21 days
1992	39 days
1993	27 days
1994	35 days
1995	24 days
1996	28 days
1997	30 days
1998	36 days
1999	68 days
2000	28 days
2001	30 days
2002	48 days
2003	27 days
2004	24 days
2005	37 days
2006	35 days
2007	40 days
2008	22 days
2009	27 days
2010	29 days
2011	32 days
2012	29 days
2013	22 days
2014	18 days
2015	34 days
2016	30 days
2017	27 days
2018	33 days
2019	23 days
2020	40 days
2021	28 days
2022	26 days
2023	25 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

63 years, 1952 to 2022

A day with at least 49.0 mm (1.9 in) of rain is expected about once in 2 years. A day with at least 129.0 mm (5.1 in) of rain is expected about once in 100 years.

Rainfall return levels at Iroquois: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	49.0 mm (1.9 in)
5 years	66.7 mm (2.6 in)
10 years	79.8 mm (3.1 in)
25 years	98.0 mm (3.9 in)
50 years	112.9 mm (4.4 in)
100 years	129.0 mm (5.1 in)	Longer than the 63 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, 63 years of values from 1952 to 2022.

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: 132.1 mm (5.2 in) in 1986; 99.1 mm (3.9 in) in 1972; 99.1 mm (3.9 in) in 1991.

Download the Data

Data for Iroquois standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Iroquois 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