Record envelope, standing records and threshold days for Mahnomen (USC00215012), Minnesota, United States, with 100 years of record.
Key Facts for Mahnomen
Mahnomen (USC00215012) is a weather station in Minnesota, United States at 47.32 latitude and -95.97 longitude, 369 m (1,212 ft) above sea level.
The station reports from 1927 to 2026, 100 years of record.
1,464 records set at Mahnomen still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Mahnomen tied a daily record high maximum temperature of 33.3 C (91.9 F) on 8 June 2026.
About the Station
Location: Minnesota, United States, 47.32 latitude, -95.97 longitude.
Elevation: 369 m (1,212 ft).
Period of record: 1927 to 2026, 100 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
7 days at or beyond a record
Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Mahnomen. The lines show the 2026 daily maximum and minimum. 7 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Mahnomen, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
10.6 C (51.1 F)
-42.2 C (-44.0 F)
3.3 C (37.9 F)
-37.8 C (-36.0 F)
Feb
12.8 C (55.0 F)
-47.2 C (-53.0 F)
7.8 C (46.0 F)
-27.8 C (-18.0 F)
Mar
26.1 C (79.0 F)
-36.7 C (-34.1 F)
14.4 C (57.9 F)
-22.2 C (-8.0 F)
Apr
35.6 C (96.1 F)
-23.3 C (-9.9 F)
30.0 C (86.0 F)
-21.1 C (-6.0 F)
May
35.6 C (96.1 F)
-12.2 C (10.0 F)
35.6 C (96.1 F)
-4.4 C (24.1 F)
Jun
37.8 C (100.0 F)
-3.3 C (26.1 F)
33.3 C (91.9 F)
6.7 C (44.1 F)
Jul
39.4 C (102.9 F)
2.2 C (36.0 F)
n/a
n/a
Aug
39.4 C (102.9 F)
-2.8 C (27.0 F)
31.7 C (89.1 F)
7.2 C (45.0 F)
Sep
36.7 C (98.1 F)
-10.0 C (14.0 F)
18.3 C (64.9 F)
3.9 C (39.0 F)
Oct
31.7 C (89.1 F)
-15.6 C (3.9 F)
n/a
n/a
Nov
22.2 C (72.0 F)
-37.2 C (-35.0 F)
n/a
n/a
Dec
13.3 C (55.9 F)
-39.4 C (-38.9 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Mahnomen still stand. 1931 holds the most, with 55.
Standing records at Mahnomen by the year they were set
Year set
Standing records
1927
13
1928
31
1929
40
1930
41
1931
55
1932
12
1933
12
1935
7
1936
7
1959
10
1960
10
1961
21
1962
35
1963
36
1964
30
1965
34
1966
31
1967
18
1968
29
1969
23
1970
12
1971
14
1972
30
1973
13
1974
25
1975
26
1976
36
1977
33
1978
27
1979
26
1980
29
1981
18
1982
14
1983
27
1984
21
1985
21
1986
15
1987
32
1988
36
1989
33
1990
36
1991
39
1992
40
1993
26
1994
23
1995
21
1996
30
1997
17
1998
18
2009
1
2010
13
2011
14
2012
30
2017
21
2018
9
2019
16
2020
18
2021
20
2022
15
2023
14
2024
18
2025
36
2026
6
All-Time Record Progression
13 new records
13 all-time records were set at Mahnomen between 25 July 1993 and 10 March 2019. Each dot is a new record.
When Mahnomen set new all-time records
Date
Kind
Detail
1993-07-25
Record daily precipitation
Record daily precipitation 119.4 mm (4.7 in)
1996-02-01
Record low minimum temperature
Record low minimum temperature -47.2 C (-53.0 F)
1996-02-02
Record low maximum temperature
Record low maximum temperature -32.8 C (-27.0 F)
1997-01-16
Record snow depth
Record snow depth 73.7 cm (29.0 in)
1997-01-18
Record snow depth
Record snow depth 76.2 cm (30.0 in)
1997-01-22
Record snow depth
Record snow depth 81.3 cm (32.0 in)
1997-01-27
Record snow depth
Record snow depth 83.8 cm (33.0 in)
1997-02-04
Record snow depth
Record snow depth 94.0 cm (37.0 in)
1997-02-10
Record snow depth
Record snow depth 99.1 cm (39.0 in)
1997-02-14
Record snow depth
Record snow depth 101.6 cm (40.0 in)
1997-02-15
Record snow depth
Record snow depth 109.2 cm (43.0 in)
1997-02-17
Record snow depth
Record snow depth 111.8 cm (44.0 in)
2019-03-10
Record daily snowfall
Record daily snowfall 36.8 cm (14.5 in)
Wettest Day of Each Month
Jul: 119.4 mm (4.7 in)
The wettest day on record for each calendar month at Mahnomen. The most was 119.4 mm (4.7 in) on 25 July 1993.
Record daily precipitation for each month at Mahnomen
Month
Record daily precipitation (mm)
Date
Jan
25.4 mm (1.0 in)
17 January 1935
Feb
27.9 mm (1.1 in)
27 February 2024
Mar
40.6 mm (1.6 in)
12 March 2023
Apr
90.2 mm (3.6 in)
21 April 2025
May
114.3 mm (4.5 in)
29 May 1949
Jun
104.1 mm (4.1 in)
25 June 1950
Jul
119.4 mm (4.7 in)
25 July 1993
Aug
88.9 mm (3.5 in)
13 August 1945
Sep
101.6 mm (4.0 in)
1 September 1973
Oct
113.0 mm (4.4 in)
14 October 1984
Nov
38.1 mm (1.5 in)
18 November 1958
Dec
40.6 mm (1.6 in)
19 December 2022
Period of Record Coverage
1927 to 2026
Complete yearUnder 90 percent of days
65 years of record at Mahnomen, 1927 to 2026. 20 years have data for under 90 percent of days and are left out of rankings: 1927, 1928, 1929, 1930, 1932, 1933, 1934, 1935 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 45 complete years at Mahnomen, 1929 to 2025. Blue stripes are years cooler than the station's own mean of 4.5 C (40.1 F); red stripes are warmer. The coolest year was 1929, at 2.2 C (35.9 F), and the warmest was 1987, at 7.5 C (45.4 F). The strongest colour marks a difference of 3.0 C (5.4 F).
Annual mean temperature at Mahnomen as warming stripes, 1929 to 2025
Year
Annual mean temperature
Difference from the station mean
1929
2.2 C
-2.32 C
1931
5.8 C
+1.27 C
1960
3.9 C
-0.63 C
1962
4.0 C
-0.49 C
1963
5.1 C
+0.62 C
1964
4.5 C
+0.03 C
1965
3.0 C
-1.47 C
1966
3.2 C
-1.33 C
1967
3.5 C
-0.96 C
1968
4.3 C
-0.25 C
1969
3.8 C
-0.73 C
1970
3.5 C
-0.98 C
1971
3.9 C
-0.64 C
1972
2.9 C
-1.61 C
1973
5.5 C
+1.04 C
1974
4.2 C
-0.28 C
1975
4.2 C
-0.26 C
1976
4.6 C
+0.10 C
1977
4.8 C
+0.29 C
1978
3.4 C
-1.14 C
1979
2.4 C
-2.10 C
1980
4.5 C
+0.03 C
1981
6.0 C
+1.54 C
1982
3.8 C
-0.71 C
1983
5.4 C
+0.90 C
1984
5.3 C
+0.79 C
1985
3.3 C
-1.20 C
1986
5.3 C
+0.83 C
1987
7.5 C
+2.96 C
1988
5.4 C
+0.90 C
1989
3.4 C
-1.08 C
1990
6.0 C
+1.46 C
1991
5.7 C
+1.15 C
1992
4.8 C
+0.27 C
1993
3.7 C
-0.82 C
1994
5.0 C
+0.53 C
1995
4.2 C
-0.29 C
1996
3.6 C
-0.88 C
1997
4.8 C
+0.28 C
1998
6.6 C
+2.05 C
2010
5.4 C
+0.87 C
2011
5.0 C
+0.53 C
2017
5.2 C
+0.67 C
2020
5.0 C
+0.53 C
2025
5.0 C
+0.48 C
The annual mean temperature here has risen by 0.21 C (0.05 to 0.37) per decade over 1929 to 2025. In Fahrenheit: 0.4 F (0.1 to 0.7) per decade. The slope is a straight line fitted to 45 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Mahnomen
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.21 C (0.05 to 0.37) per decade
0.4 F (0.1 to 0.7) per decade
1929 to 2025
45
Rise
Mean daily maximum
0.1 C (-0.1 to 0.3) per decade
0.2 F (-0.1 to 0.5) per decade
1929 to 2025
45
Not clearly different from zero
Mean daily minimum
0.3 C (0.1 to 0.5) per decade
0.5 F (0.2 to 0.8) per decade
1929 to 2025
45
Rise
A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.
Extremes by Year
1927 to 2026
Yearly extremes at Mahnomen: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
39.4 C (102.9 F)
1929
34.4 C (93.9 F)
65
Coldest night (TNn)
-47.2 C (-53.0 F)
1996
-36.7 C (-34.1 F)
66
Wettest day (Rx1day)
119.4 mm (4.7 in)
1993
48.3 mm (1.9 in)
87
Wettest five days (Rx5day)
231.8 mm (9.1 in)
1973
72.9 mm (2.9 in)
85
Longest dry spell (CDD)
62 days
1980
24 days
87
Hottest day (TXx)
The hottest day of the year at Mahnomen, 1927 to 2026. The record is 39.4 C (102.9 F) in 1929, marked on the chart; the median year is 34.4 C (93.9 F).
Hottest day (TXx) at Mahnomen by year
Year
Hottest day (TXx)
1927
31.1 C (88.0 F)
1928
33.9 C (93.0 F)
1929
39.4 C (102.9 F)
1930
36.7 C (98.1 F)
1931
37.2 C (99.0 F)
1932
36.1 C (97.0 F)
1933
35.6 C (96.1 F)
1934
-12.2 C (10.0 F)
1935
18.9 C (66.0 F)
1936
n/a
1937
n/a
1938
n/a
1939
n/a
1940
n/a
1941
n/a
1942
n/a
1943
n/a
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
34.4 C (93.9 F)
1960
32.2 C (90.0 F)
1961
36.1 C (97.0 F)
1962
32.2 C (90.0 F)
1963
33.3 C (91.9 F)
1964
33.9 C (93.0 F)
1965
35.0 C (95.0 F)
1966
34.4 C (93.9 F)
1967
34.4 C (93.9 F)
1968
34.4 C (93.9 F)
1969
35.0 C (95.0 F)
1970
34.4 C (93.9 F)
1971
33.9 C (93.0 F)
1972
32.8 C (91.0 F)
1973
33.3 C (91.9 F)
1974
34.4 C (93.9 F)
1975
35.0 C (95.0 F)
1976
39.4 C (102.9 F)
1977
36.7 C (98.1 F)
1978
36.7 C (98.1 F)
1979
33.3 C (91.9 F)
1980
37.2 C (99.0 F)
1981
33.3 C (91.9 F)
1982
33.3 C (91.9 F)
1983
38.3 C (100.9 F)
1984
35.0 C (95.0 F)
1985
33.3 C (91.9 F)
1986
33.9 C (93.0 F)
1987
35.0 C (95.0 F)
1988
38.9 C (102.0 F)
1989
37.2 C (99.0 F)
1990
35.0 C (95.0 F)
1991
35.0 C (95.0 F)
1992
32.2 C (90.0 F)
1993
32.2 C (90.0 F)
1994
31.1 C (88.0 F)
1995
36.1 C (97.0 F)
1996
35.0 C (95.0 F)
1997
33.3 C (91.9 F)
1998
33.3 C (91.9 F)
2009
15.6 C (60.1 F)
2010
32.8 C (91.0 F)
2011
34.4 C (93.9 F)
2012
23.9 C (75.0 F)
2013
30.0 C (86.0 F)
2016
3.3 C (37.9 F)
2017
32.8 C (91.0 F)
2018
33.3 C (91.9 F)
2019
32.2 C (90.0 F)
2020
34.4 C (93.9 F)
2021
37.8 C (100.0 F)
2022
37.2 C (99.0 F)
2023
33.9 C (93.0 F)
2024
18.9 C (66.0 F)
2025
33.9 C (93.0 F)
2026
35.6 C (96.1 F)
Coldest night (TNn)
The coldest night of the year at Mahnomen, 1927 to 2026. The record is -47.2 C (-53.0 F) in 1996, marked on the chart; the median year is -36.7 C (-34.1 F).
Coldest night (TNn) at Mahnomen by year
Year
Coldest night (TNn)
1927
-32.2 C (-26.0 F)
1928
-38.9 C (-38.0 F)
1929
-40.0 C (-40.0 F)
1930
-37.8 C (-36.0 F)
1931
-31.1 C (-24.0 F)
1932
-32.8 C (-27.0 F)
1933
-40.6 C (-41.1 F)
1934
-36.7 C (-34.1 F)
1935
-40.0 C (-40.0 F)
1936
-45.6 C (-50.1 F)
1937
n/a
1938
n/a
1939
n/a
1940
n/a
1941
n/a
1942
n/a
1943
n/a
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
-23.3 C (-9.9 F)
1960
-32.8 C (-27.0 F)
1961
-35.6 C (-32.1 F)
1962
-38.3 C (-36.9 F)
1963
-36.1 C (-33.0 F)
1964
-35.6 C (-32.1 F)
1965
-39.4 C (-38.9 F)
1966
-38.9 C (-38.0 F)
1967
-37.2 C (-35.0 F)
1968
-40.6 C (-41.1 F)
1969
-37.8 C (-36.0 F)
1970
-39.4 C (-38.9 F)
1971
-38.9 C (-38.0 F)
1972
-37.2 C (-35.0 F)
1973
-38.3 C (-36.9 F)
1974
-38.9 C (-38.0 F)
1975
-32.2 C (-26.0 F)
1976
-37.2 C (-35.0 F)
1977
-42.2 C (-44.0 F)
1978
-35.6 C (-32.1 F)
1979
-37.2 C (-35.0 F)
1980
-37.2 C (-35.0 F)
1981
-33.3 C (-27.9 F)
1982
-38.3 C (-36.9 F)
1983
-36.1 C (-33.0 F)
1984
-35.6 C (-32.1 F)
1985
-37.2 C (-35.0 F)
1986
-36.7 C (-34.1 F)
1987
-33.3 C (-27.9 F)
1988
-35.6 C (-32.1 F)
1989
-40.0 C (-40.0 F)
1990
-39.4 C (-38.9 F)
1991
-34.4 C (-29.9 F)
1992
-36.7 C (-34.1 F)
1993
-36.1 C (-33.0 F)
1994
-41.1 C (-42.0 F)
1995
-33.3 C (-27.9 F)
1996
-47.2 C (-53.0 F)
1997
-35.0 C (-31.0 F)
1998
-33.9 C (-29.0 F)
2009
-7.2 C (19.0 F)
2010
-36.1 C (-33.0 F)
2011
-35.6 C (-32.1 F)
2012
-28.9 C (-20.0 F)
2013
-4.4 C (24.1 F)
2016
-30.6 C (-23.1 F)
2017
-33.9 C (-29.0 F)
2018
-33.9 C (-29.0 F)
2019
-37.8 C (-36.0 F)
2020
-32.8 C (-27.0 F)
2021
-39.4 C (-38.9 F)
2022
-40.0 C (-40.0 F)
2023
-31.1 C (-24.0 F)
2024
-30.0 C (-22.0 F)
2025
-35.6 C (-32.1 F)
2026
-37.8 C (-36.0 F)
Wettest day (Rx1day)
The wettest day of the year at Mahnomen, 1927 to 2026. The record is 119.4 mm (4.7 in) in 1993, marked on the chart; the median year is 48.3 mm (1.9 in).
Wettest day (Rx1day) at Mahnomen by year
Year
Wettest day (Rx1day)
1927
35.6 mm (1.4 in)
1928
59.2 mm (2.3 in)
1929
27.7 mm (1.1 in)
1930
44.2 mm (1.7 in)
1931
35.6 mm (1.4 in)
1932
28.7 mm (1.1 in)
1933
51.8 mm (2.0 in)
1934
51.6 mm (2.0 in)
1935
58.4 mm (2.3 in)
1936
17.8 mm (0.7 in)
1937
49.0 mm (1.9 in)
1938
40.1 mm (1.6 in)
1939
56.9 mm (2.2 in)
1940
41.1 mm (1.6 in)
1941
64.5 mm (2.5 in)
1942
54.9 mm (2.2 in)
1943
85.9 mm (3.4 in)
1944
61.5 mm (2.4 in)
1945
88.9 mm (3.5 in)
1946
47.0 mm (1.9 in)
1947
41.9 mm (1.6 in)
1948
20.1 mm (0.8 in)
1949
114.3 mm (4.5 in)
1950
104.1 mm (4.1 in)
1951
27.9 mm (1.1 in)
1952
74.2 mm (2.9 in)
1953
43.2 mm (1.7 in)
1954
35.6 mm (1.4 in)
1955
43.9 mm (1.7 in)
1956
47.0 mm (1.9 in)
1957
68.6 mm (2.7 in)
1958
48.8 mm (1.9 in)
1959
43.2 mm (1.7 in)
1960
49.5 mm (1.9 in)
1961
75.7 mm (3.0 in)
1962
71.1 mm (2.8 in)
1963
99.1 mm (3.9 in)
1964
63.5 mm (2.5 in)
1965
53.3 mm (2.1 in)
1966
56.6 mm (2.2 in)
1967
38.1 mm (1.5 in)
1968
46.0 mm (1.8 in)
1969
61.5 mm (2.4 in)
1970
41.9 mm (1.6 in)
1971
67.1 mm (2.6 in)
1972
51.1 mm (2.0 in)
1973
101.6 mm (4.0 in)
1974
33.3 mm (1.3 in)
1975
55.9 mm (2.2 in)
1976
23.4 mm (0.9 in)
1977
34.3 mm (1.4 in)
1978
42.7 mm (1.7 in)
1979
49.3 mm (1.9 in)
1980
30.7 mm (1.2 in)
1981
50.8 mm (2.0 in)
1982
29.2 mm (1.1 in)
1983
47.5 mm (1.9 in)
1984
113.0 mm (4.4 in)
1985
50.8 mm (2.0 in)
1986
43.2 mm (1.7 in)
1987
60.7 mm (2.4 in)
1988
50.3 mm (2.0 in)
1989
45.7 mm (1.8 in)
1990
35.6 mm (1.4 in)
1991
48.3 mm (1.9 in)
1992
80.5 mm (3.2 in)
1993
119.4 mm (4.7 in)
1994
69.9 mm (2.8 in)
1995
44.5 mm (1.8 in)
1996
46.2 mm (1.8 in)
1997
38.9 mm (1.5 in)
1998
48.3 mm (1.9 in)
2009
19.1 mm (0.8 in)
2010
56.9 mm (2.2 in)
2011
40.6 mm (1.6 in)
2012
16.0 mm (0.6 in)
2013
41.9 mm (1.6 in)
2016
n/a
2017
37.1 mm (1.5 in)
2018
80.8 mm (3.2 in)
2019
46.7 mm (1.8 in)
2020
64.3 mm (2.5 in)
2021
20.6 mm (0.8 in)
2022
56.1 mm (2.2 in)
2023
40.6 mm (1.6 in)
2024
27.9 mm (1.1 in)
2025
90.2 mm (3.6 in)
2026
25.9 mm (1.0 in)
Wettest five days (Rx5day)
The wettest five days of the year at Mahnomen, 1927 to 2026. The record is 231.8 mm (9.1 in) in 1973, marked on the chart; the median year is 72.9 mm (2.9 in).
Wettest five days (Rx5day) at Mahnomen by year
Year
Wettest five days (Rx5day)
1927
29.9 mm (1.2 in)
1928
80.0 mm (3.1 in)
1929
31.6 mm (1.2 in)
1930
104.9 mm (4.1 in)
1931
63.8 mm (2.5 in)
1932
42.6 mm (1.7 in)
1933
61.5 mm (2.4 in)
1934
92.2 mm (3.6 in)
1935
129.5 mm (5.1 in)
1936
24.1 mm (0.9 in)
1937
49.0 mm (1.9 in)
1938
70.1 mm (2.8 in)
1939
82.3 mm (3.2 in)
1940
76.4 mm (3.0 in)
1941
130.5 mm (5.1 in)
1942
99.1 mm (3.9 in)
1943
101.6 mm (4.0 in)
1944
73.7 mm (2.9 in)
1945
94.3 mm (3.7 in)
1946
56.4 mm (2.2 in)
1947
63.7 mm (2.5 in)
1948
25.4 mm (1.0 in)
1949
157.2 mm (6.2 in)
1950
127.4 mm (5.0 in)
1951
75.2 mm (3.0 in)
1952
104.9 mm (4.1 in)
1953
51.6 mm (2.0 in)
1954
55.7 mm (2.2 in)
1955
58.9 mm (2.3 in)
1956
51.0 mm (2.0 in)
1957
75.5 mm (3.0 in)
1958
72.9 mm (2.9 in)
1959
53.4 mm (2.1 in)
1960
59.3 mm (2.3 in)
1961
82.0 mm (3.2 in)
1962
91.9 mm (3.6 in)
1963
108.0 mm (4.3 in)
1964
100.3 mm (3.9 in)
1965
60.9 mm (2.4 in)
1966
56.9 mm (2.2 in)
1967
66.0 mm (2.6 in)
1968
55.1 mm (2.2 in)
1969
62.0 mm (2.4 in)
1970
71.1 mm (2.8 in)
1971
78.7 mm (3.1 in)
1972
103.4 mm (4.1 in)
1973
231.8 mm (9.1 in)
1974
70.4 mm (2.8 in)
1975
137.4 mm (5.4 in)
1976
44.7 mm (1.8 in)
1977
49.2 mm (1.9 in)
1978
61.2 mm (2.4 in)
1979
87.4 mm (3.4 in)
1980
55.8 mm (2.2 in)
1981
78.0 mm (3.1 in)
1982
75.5 mm (3.0 in)
1983
71.7 mm (2.8 in)
1984
169.7 mm (6.7 in)
1985
96.0 mm (3.8 in)
1986
64.9 mm (2.6 in)
1987
121.7 mm (4.8 in)
1988
80.3 mm (3.2 in)
1989
68.6 mm (2.7 in)
1990
39.7 mm (1.6 in)
1991
93.7 mm (3.7 in)
1992
117.4 mm (4.6 in)
1993
145.6 mm (5.7 in)
1994
89.3 mm (3.5 in)
1995
86.6 mm (3.4 in)
1996
62.5 mm (2.5 in)
1997
72.1 mm (2.8 in)
1998
100.9 mm (4.0 in)
2009
34.1 mm (1.3 in)
2010
80.8 mm (3.2 in)
2011
n/a
2012
10.9 mm (0.4 in)
2013
86.9 mm (3.4 in)
2016
n/a
2017
30.4 mm (1.2 in)
2018
89.9 mm (3.5 in)
2019
n/a
2020
71.9 mm (2.8 in)
2021
22.6 mm (0.9 in)
2022
79.5 mm (3.1 in)
2023
47.0 mm (1.9 in)
2024
34.1 mm (1.3 in)
2025
93.5 mm (3.7 in)
2026
22.9 mm (0.9 in)
Longest dry spell (CDD)
The longest dry spell of the year at Mahnomen, 1927 to 2026. The record is 62 days in 1980, marked on the chart; the median year is 24 days.
Longest dry spell (CDD) at Mahnomen by year
Year
Longest dry spell (CDD)
1927
19 days
1928
26 days
1929
24 days
1930
29 days
1931
36 days
1932
39 days
1933
36 days
1934
25 days
1935
44 days
1936
37 days
1937
38 days
1938
39 days
1939
41 days
1940
30 days
1941
23 days
1942
36 days
1943
29 days
1944
31 days
1945
22 days
1946
16 days
1947
29 days
1948
38 days
1949
34 days
1950
20 days
1951
18 days
1952
30 days
1953
24 days
1954
26 days
1955
24 days
1956
32 days
1957
28 days
1958
18 days
1959
28 days
1960
34 days
1961
28 days
1962
19 days
1963
26 days
1964
27 days
1965
20 days
1966
18 days
1967
25 days
1968
12 days
1969
16 days
1970
16 days
1971
23 days
1972
16 days
1973
31 days
1974
40 days
1975
22 days
1976
40 days
1977
18 days
1978
35 days
1979
20 days
1980
62 days
1981
20 days
1982
17 days
1983
22 days
1984
19 days
1985
18 days
1986
33 days
1987
18 days
1988
33 days
1989
28 days
1990
45 days
1991
20 days
1992
27 days
1993
22 days
1994
22 days
1995
28 days
1996
19 days
1997
22 days
1998
29 days
2009
7 days
2010
21 days
2011
2 days
2012
12 days
2013
9 days
2016
n/a
2017
7 days
2018
9 days
2019
2 days
2020
18 days
2021
24 days
2022
38 days
2023
24 days
2024
25 days
2025
36 days
2026
20 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.
Frost Dates and Growing Season
45 years with a frost
Across 45 years with a frost, the median last spring frost at Mahnomen falls on 15 May and the median first autumn frost on 20 September, which leaves a median of 127 days between them.
Fitted over all years, the growing season changes by +5.9 days per decade at this station.
Frost dates and growing season at Mahnomen
Measure
Median, all years
Earliest period
Recent period (1974 to 2025)
Recent against earliest
Fitted trend
Last spring frost
15 May
n/a
13 May
n/a
-3.3 days per decade
First autumn frost
20 September
n/a
22 September
n/a
+2.6 days per decade
Growing days
127 days
n/a
134 days
n/a
+5.9 days per decade
A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.
Rainfall Return Levels
68 years, 1929 to 2025
A day with at least 49.4 mm (1.9 in) of rain is expected about once in 2 years. A day with at least 137.5 mm (5.4 in) of rain is expected about once in 100 years.
Rainfall return levels at Mahnomen: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
49.4 mm (1.9 in)
5 years
68.5 mm (2.7 in)
10 years
82.7 mm (3.3 in)
25 years
102.8 mm (4.0 in)
50 years
119.4 mm (4.7 in)
100 years
137.5 mm (5.4 in)
Longer than the 68 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, 68 years of values from 1929 to 2025.
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: 119.4 mm (4.7 in) in 1993; 114.3 mm (4.5 in) in 1949; 113.0 mm (4.4 in) in 1984.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Download the Data
Data for Mahnomen standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Mahnomen 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.