Riverton Weather Records (USC00137085)

Record envelope, standing records and threshold days for Riverton (USC00137085), Iowa, United States, with 35 years of record.

Key Facts for Riverton

Riverton (USC00137085) is a weather station in Iowa, United States at 40.68 latitude and -95.57 longitude, 281 m (922 ft) above sea level.
The station reports from 1926 to 1960, 35 years of record.
1,216 records set at Riverton still stand.
Records are tracked for prcp, snow: an element needs 30 years of data to be eligible.
Riverton set a daily record snowfall of 5.1 cm (2.0 in) on 5 February 1960.

About the Station

Location: Iowa, United States, 40.68 latitude, -95.57 longitude.
Elevation: 281 m (922 ft).
Period of record: 1926 to 1960, 35 years.
Eligible elements: prcp, snow.

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 Riverton. 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 Riverton, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	17.8 C (64.0 F)	-27.8 C (-18.0 F)	n/a	n/a
Feb	23.3 C (73.9 F)	-25.0 C (-13.0 F)	n/a	n/a
Mar	28.9 C (84.0 F)	-16.1 C (3.0 F)	n/a	n/a
Apr	31.1 C (88.0 F)	-7.8 C (18.0 F)	n/a	n/a
May	35.0 C (95.0 F)	-1.1 C (30.0 F)	n/a	n/a
Jun	40.0 C (104.0 F)	7.8 C (46.0 F)	n/a	n/a
Jul	40.0 C (104.0 F)	13.3 C (55.9 F)	n/a	n/a
Aug	43.3 C (109.9 F)	8.3 C (46.9 F)	n/a	n/a
Sep	40.0 C (104.0 F)	-3.3 C (26.1 F)	n/a	n/a
Oct	35.0 C (95.0 F)	-12.8 C (9.0 F)	n/a	n/a
Nov	23.3 C (73.9 F)	-17.8 C (0.0 F)	n/a	n/a
Dec	22.2 C (72.0 F)	-25.6 C (-14.1 F)	n/a	n/a

Which Years Hold Standing Records

1,216 standing records

1,216 records at Riverton still stand. 1926 holds the most, with 364.

Wettest Day of Each Month

Aug: 194.1 mm (7.6 in)

The wettest day on record for each calendar month at Riverton. The most was 194.1 mm (7.6 in) on 31 August 1932.

Record daily precipitation for each month at Riverton
Month	Record daily precipitation (mm)	Date
Jan	34.5 mm (1.4 in)	3 January 1949
Feb	39.9 mm (1.6 in)	6 February 1928
Mar	49.0 mm (1.9 in)	31 March 1927
Apr	57.7 mm (2.3 in)	14 April 1929
May	71.4 mm (2.8 in)	21 May 1945
Jun	159.5 mm (6.3 in)	9 June 1941
Jul	93.0 mm (3.7 in)	19 July 1958
Aug	194.1 mm (7.6 in)	31 August 1932
Sep	108.0 mm (4.3 in)	4 September 1946
Oct	113.8 mm (4.5 in)	5 October 1954
Nov	61.0 mm (2.4 in)	1 November 1941
Dec	60.5 mm (2.4 in)	31 December 1931

Period of Record Coverage

1926 to 1943

17 years of record at Riverton, 1926 to 1943. 17 years have data for under 90 percent of days and are left out of rankings: 1926, 1927, 1928, 1929, 1930, 1931, 1932, 1933 and others.

Days with data per year at Riverton
Year	Days with data	Share of year	Complete
1926	122	33%	No
1927	4	1%	No
1928	11	3%	No
1929	6	2%	No
1930	31	8%	No
1931	27	7%	No
1932	20	5%	No
1933	46	13%	No
1935	4	1%	No
1936	18	5%	No
1937	12	3%	No
1938	31	8%	No
1939	66	18%	No
1940	111	30%	No
1941	9	2%	No
1942	53	15%	No
1943	25	7%	No

Latest Records

Latest records at Riverton
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
5 February 1960	Riverton, US	daily snowfall	5.1 cm (2.0 in)	5.1 cm (2.0 in)	32 years	19 of 100 (Routine)
18 January 1960	Riverton, US	daily snowfall (Tie)	5.1 cm (2.0 in)	tie	16 years	2 of 100 (Routine)
15 January 1960	Riverton, US	daily rain	18.5 mm (0.7 in)	13.2 mm (0.5 in)	10 years	20 of 100 (Routine)
12 January 1960	Riverton, US	daily rain	25.1 mm (1.0 in)	18.2 mm (0.7 in)	1 year	36 of 100 (Notable)
27 December 1959	Riverton, US	daily rain	23.6 mm (0.9 in)	13.4 mm (0.5 in)	16 years	20 of 100 (Routine)
5 November 1959	Riverton, US	daily snowfall	3.8 cm (1.5 in)	3.0 cm (1.2 in)	17 years	16 of 100 (Routine)
18 September 1959	Riverton, US	daily rain	29.2 mm (1.1 in)	15.2 mm (0.6 in)	14 years	16 of 100 (Routine)
17 September 1959	Riverton, US	daily rain	37.1 mm (1.5 in)	22.9 mm (0.9 in)	32 years	25 of 100 (Routine)
29 August 1959	Riverton, US	daily rain	44.5 mm (1.8 in)	22.1 mm (0.9 in)	6 years	16 of 100 (Routine)
30 June 1959	Riverton, US	daily rain	89.9 mm (3.5 in)	62.7 mm (2.5 in)	2 years	36 of 100 (Notable)
18 May 1959	Riverton, US	daily rain	21.6 mm (0.9 in)	5.9 mm (0.23 in)	18 years	12 of 100 (Routine)
3 May 1959	Riverton, US	daily rain	23.6 mm (0.9 in)	6.6 mm (0.26 in)	14 years	12 of 100 (Routine)
17 April 1959	Riverton, US	daily rain	25.9 mm (1.0 in)	10.7 mm (0.4 in)	20 years	19 of 100 (Routine)
29 January 1959	Riverton, US	daily snowfall	5.1 cm (2.0 in)	2.6 cm (1.0 in)	25 years	15 of 100 (Routine)
15 November 1958	Riverton, US	daily rain	22.9 mm (0.9 in)	15.5 mm (0.6 in)	11 years	19 of 100 (Routine)
13 August 1958	Riverton, US	daily rain	26.9 mm (1.1 in)	4.3 mm (0.17 in)	8 years	7 of 100 (Routine)
6 August 1958	Riverton, US	daily rain	64.8 mm (2.6 in)	36.9 mm (1.5 in)	20 years	29 of 100 (Routine)
19 July 1958	Riverton, US	monthly rain	93.0 mm (3.7 in)	9.7 mm (0.38 in)	20 years	25 of 100 (Routine)
17 July 1958	Riverton, US	daily rain	20.8 mm (0.8 in)	3.8 mm (0.15 in)	24 years	12 of 100 (Routine)
10 July 1958	Riverton, US	daily rain	20.1 mm (0.8 in)	13.7 mm (0.5 in)	7 years	14 of 100 (Routine)

Extremes by Year

1926 to 1960

Yearly extremes at Riverton: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	43.3 C (109.9 F)	1936	38.9 C (102.0 F)	17
Coldest night (TNn)	-27.8 C (-18.0 F)	1940	-21.1 C (-6.0 F)	17
Wettest day (Rx1day)	194.1 mm (7.6 in)	1932	66.5 mm (2.6 in)	35
Wettest five days (Rx5day)	278.7 mm (11.0 in)	1932	100.1 mm (3.9 in)	35
Longest dry spell (CDD)	54 days	1952	26 days	35

Hottest day (TXx)

The hottest day of the year at Riverton, 1926 to 1960. The record is 43.3 C (109.9 F) in 1936, marked on the chart; the median year is 38.9 C (102.0 F).

Hottest day (TXx) at Riverton by year
Year	Hottest day (TXx)
1926	38.9 C (102.0 F)
1927	33.9 C (93.0 F)
1928	28.9 C (84.0 F)
1929	34.4 C (93.9 F)
1930	40.0 C (104.0 F)
1931	38.9 C (102.0 F)
1932	34.4 C (93.9 F)
1933	40.0 C (104.0 F)
1934	n/a
1935	40.0 C (104.0 F)
1936	43.3 C (109.9 F)
1937	38.9 C (102.0 F)
1938	38.9 C (102.0 F)
1939	40.0 C (104.0 F)
1940	28.9 C (84.0 F)
1941	37.8 C (100.0 F)
1942	34.4 C (93.9 F)
1943	12.2 C (54.0 F)
1944	n/a
1945	n/a
1946	n/a
1947	n/a
1948	n/a
1949	n/a
1950	n/a
1951	n/a
1952	n/a
1953	n/a
1954	n/a
1955	n/a
1956	n/a
1957	n/a
1958	n/a
1959	n/a
1960	n/a

Coldest night (TNn)

The coldest night of the year at Riverton, 1926 to 1960. The record is -27.8 C (-18.0 F) in 1940, marked on the chart; the median year is -21.1 C (-6.0 F).

Coldest night (TNn) at Riverton by year
Year	Coldest night (TNn)
1926	-7.8 C (18.0 F)
1927	-21.1 C (-6.0 F)
1928	-21.7 C (-7.1 F)
1929	-22.2 C (-8.0 F)
1930	-13.3 C (8.1 F)
1931	-6.1 C (21.0 F)
1932	-25.6 C (-14.1 F)
1933	-25.0 C (-13.0 F)
1934	n/a
1935	-21.1 C (-6.0 F)
1936	-18.9 C (-2.0 F)
1937	-17.8 C (0.0 F)
1938	-15.6 C (3.9 F)
1939	-22.8 C (-9.0 F)
1940	-27.8 C (-18.0 F)
1941	-13.3 C (8.1 F)
1942	-18.9 C (-2.0 F)
1943	-25.6 C (-14.1 F)
1944	n/a
1945	n/a
1946	n/a
1947	n/a
1948	n/a
1949	n/a
1950	n/a
1951	n/a
1952	n/a
1953	n/a
1954	n/a
1955	n/a
1956	n/a
1957	n/a
1958	n/a
1959	n/a
1960	n/a

Wettest day (Rx1day)

The wettest day of the year at Riverton, 1926 to 1960. The record is 194.1 mm (7.6 in) in 1932, marked on the chart; the median year is 66.5 mm (2.6 in).

Wettest day (Rx1day) at Riverton by year
Year	Wettest day (Rx1day)
1926	65.3 mm (2.6 in)
1927	50.8 mm (2.0 in)
1928	89.4 mm (3.5 in)
1929	74.7 mm (2.9 in)
1930	68.1 mm (2.7 in)
1931	66.5 mm (2.6 in)
1932	194.1 mm (7.6 in)
1933	66.3 mm (2.6 in)
1934	55.9 mm (2.2 in)
1935	50.3 mm (2.0 in)
1936	77.5 mm (3.1 in)
1937	83.3 mm (3.3 in)
1938	88.4 mm (3.5 in)
1939	62.2 mm (2.4 in)
1940	59.4 mm (2.3 in)
1941	159.5 mm (6.3 in)
1942	43.7 mm (1.7 in)
1943	127.0 mm (5.0 in)
1944	121.7 mm (4.8 in)
1945	75.7 mm (3.0 in)
1946	108.0 mm (4.3 in)
1947	75.2 mm (3.0 in)
1948	60.7 mm (2.4 in)
1949	49.0 mm (1.9 in)
1950	75.7 mm (3.0 in)
1951	56.9 mm (2.2 in)
1952	43.7 mm (1.7 in)
1953	36.8 mm (1.4 in)
1954	113.8 mm (4.5 in)
1955	54.9 mm (2.2 in)
1956	46.2 mm (1.8 in)
1957	46.2 mm (1.8 in)
1958	93.0 mm (3.7 in)
1959	89.9 mm (3.5 in)
1960	25.1 mm (1.0 in)

Wettest five days (Rx5day)

The wettest five days of the year at Riverton, 1926 to 1960. The record is 278.7 mm (11.0 in) in 1932, marked on the chart; the median year is 100.1 mm (3.9 in).

Wettest five days (Rx5day) at Riverton by year
Year	Wettest five days (Rx5day)
1926	180.8 mm (7.1 in)
1927	73.2 mm (2.9 in)
1928	104.7 mm (4.1 in)
1929	121.2 mm (4.8 in)
1930	68.1 mm (2.7 in)
1931	110.2 mm (4.3 in)
1932	278.7 mm (11.0 in)
1933	103.4 mm (4.1 in)
1934	93.7 mm (3.7 in)
1935	119.1 mm (4.7 in)
1936	91.0 mm (3.6 in)
1937	93.5 mm (3.7 in)
1938	123.5 mm (4.9 in)
1939	129.8 mm (5.1 in)
1940	73.4 mm (2.9 in)
1941	195.6 mm (7.7 in)
1942	98.4 mm (3.9 in)
1943	198.2 mm (7.8 in)
1944	141.2 mm (5.6 in)
1945	121.2 mm (4.8 in)
1946	152.5 mm (6.0 in)
1947	87.6 mm (3.4 in)
1948	77.8 mm (3.1 in)
1949	65.0 mm (2.6 in)
1950	123.9 mm (4.9 in)
1951	82.5 mm (3.2 in)
1952	77.5 mm (3.1 in)
1953	78.2 mm (3.1 in)
1954	127.2 mm (5.0 in)
1955	62.0 mm (2.4 in)
1956	64.2 mm (2.5 in)
1957	70.1 mm (2.8 in)
1958	124.3 mm (4.9 in)
1959	100.1 mm (3.9 in)
1960	45.4 mm (1.8 in)

Longest dry spell (CDD)

The longest dry spell of the year at Riverton, 1926 to 1960. The record is 54 days in 1952, marked on the chart; the median year is 26 days.

Longest dry spell (CDD) at Riverton by year
Year	Longest dry spell (CDD)
1926	22 days
1927	53 days
1928	36 days
1929	19 days
1930	30 days
1931	30 days
1932	29 days
1933	28 days
1934	36 days
1935	25 days
1936	32 days
1937	19 days
1938	26 days
1939	51 days
1940	21 days
1941	18 days
1942	31 days
1943	22 days
1944	26 days
1945	25 days
1946	41 days
1947	26 days
1948	21 days
1949	27 days
1950	21 days
1951	19 days
1952	54 days
1953	22 days
1954	49 days
1955	21 days
1956	32 days
1957	20 days
1958	45 days
1959	27 days
1960	10 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

32 years, 1927 to 1959

A day with at least 66.8 mm (2.6 in) of rain is expected about once in 2 years. A day with at least 216.7 mm (8.5 in) of rain is expected about once in 100 years.

Rainfall return levels at Riverton: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	66.8 mm (2.6 in)
5 years	94.0 mm (3.7 in)
10 years	116.2 mm (4.6 in)
25 years	150.4 mm (5.9 in)
50 years	181.0 mm (7.1 in)	Longer than the 32 years of record
100 years	216.7 mm (8.5 in)	Longer than the 32 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, 32 years of values from 1927 to 1959.

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: 194.1 mm (7.6 in) in 1932; 159.5 mm (6.3 in) in 1941; 121.7 mm (4.8 in) in 1944.

Download the Data

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