Record envelope, standing records and threshold days for Ontonagon (USC00206210), Michigan, United States, with 78 years of record.
Key Facts for Ontonagon
Ontonagon (USC00206210) is a weather station in Michigan, United States at 46.87 latitude and -89.32 longitude, 214 m (702 ft) above sea level.
The station reports from 1900 to 1977, 78 years of record.
1,464 records set at Ontonagon still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Ontonagon tied a daily record high minimum temperature of 13.9 C (57.0 F) on 27 May 1977.
About the Station
Location: Michigan, United States, 46.87 latitude, -89.32 longitude.
Elevation: 214 m (702 ft).
Period of record: 1900 to 1977, 78 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
0 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 Ontonagon. 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 Ontonagon, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
11.1 C (52.0 F)
-35.0 C (-31.0 F)
n/a
n/a
Feb
16.1 C (61.0 F)
-37.8 C (-36.0 F)
n/a
n/a
Mar
27.2 C (81.0 F)
-34.4 C (-29.9 F)
n/a
n/a
Apr
31.1 C (88.0 F)
-20.0 C (-4.0 F)
n/a
n/a
May
35.0 C (95.0 F)
-6.7 C (19.9 F)
n/a
n/a
Jun
37.2 C (99.0 F)
-3.3 C (26.1 F)
n/a
n/a
Jul
37.2 C (99.0 F)
0.0 C (32.0 F)
n/a
n/a
Aug
38.9 C (102.0 F)
0.6 C (33.1 F)
n/a
n/a
Sep
36.1 C (97.0 F)
-5.6 C (21.9 F)
n/a
n/a
Oct
31.1 C (88.0 F)
-7.8 C (18.0 F)
n/a
n/a
Nov
25.6 C (78.1 F)
-20.6 C (-5.1 F)
n/a
n/a
Dec
15.0 C (59.0 F)
-28.9 C (-20.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Ontonagon still stand. 1976 holds the most, with 51.
Standing records at Ontonagon by the year they were set
Year set
Standing records
1900
30
1901
43
1902
23
1903
29
1913
27
1914
32
1915
21
1938
2
1939
30
1940
27
1941
38
1942
28
1943
20
1944
29
1945
38
1946
38
1947
48
1948
34
1949
34
1950
34
1951
44
1952
24
1953
29
1954
33
1955
26
1956
29
1957
14
1958
34
1959
35
1960
22
1961
31
1962
36
1963
49
1964
49
1965
43
1966
37
1967
35
1968
24
1969
22
1970
23
1971
22
1972
50
1973
20
1974
37
1975
31
1976
51
1977
9
All-Time Record Progression
3 new records
3 all-time records were set at Ontonagon between 14 January 1963 and 19 February 1966. Each dot is a new record.
When Ontonagon set new all-time records
Date
Kind
Detail
1963-01-14
Record low minimum temperature
Record low minimum temperature -35.0 C (-31.0 F)
1963-01-23
Record low maximum temperature
Record low maximum temperature -23.9 C (-11.0 F)
1966-02-19
Record low minimum temperature
Record low minimum temperature -37.8 C (-36.0 F)
Wettest Day of Each Month
Sep: 81.3 mm (3.2 in)
The wettest day on record for each calendar month at Ontonagon. The most was 81.3 mm (3.2 in) on 17 September 1955.
Record daily precipitation for each month at Ontonagon
Month
Record daily precipitation (mm)
Date
Jan
50.8 mm (2.0 in)
29 January 1914
Feb
38.1 mm (1.5 in)
5 February 1946
Mar
56.1 mm (2.2 in)
6 March 1946
Apr
50.3 mm (2.0 in)
26 April 1954
May
58.2 mm (2.3 in)
28 May 1903
Jun
61.0 mm (2.4 in)
2 June 1944
Jul
57.9 mm (2.3 in)
1 July 1953
Aug
76.2 mm (3.0 in)
7 August 1969
Sep
81.3 mm (3.2 in)
17 September 1955
Oct
67.3 mm (2.6 in)
25 October 1967
Nov
50.8 mm (2.0 in)
10 November 1975
Dec
35.6 mm (1.4 in)
15 December 1901
Period of Record Coverage
1900 to 1977
Complete yearUnder 90 percent of days
48 years of record at Ontonagon, 1900 to 1977. 9 years have data for under 90 percent of days and are left out of rankings: 1900, 1901, 1903, 1905, 1913, 1914, 1915, 1938 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 37 complete years at Ontonagon, 1902 to 1976. Blue stripes are years cooler than the station's own mean of 5.5 C (41.8 F); red stripes are warmer. The coolest year was 1972, at 2.8 C (37.0 F), and the warmest was 1953, at 6.9 C (44.4 F). The strongest colour marks a difference of 2.8 C (5.0 F).
Annual mean temperature at Ontonagon as warming stripes, 1902 to 1976
Year
Annual mean temperature
Difference from the station mean
1902
5.1 C
-0.35 C
1939
5.5 C
+0.04 C
1940
5.2 C
-0.25 C
1941
6.7 C
+1.26 C
1942
6.0 C
+0.52 C
1945
5.0 C
-0.50 C
1946
6.6 C
+1.17 C
1947
5.5 C
+0.06 C
1948
5.8 C
+0.30 C
1949
6.7 C
+1.21 C
1950
4.2 C
-1.25 C
1951
4.6 C
-0.92 C
1952
6.6 C
+1.13 C
1953
6.9 C
+1.41 C
1954
6.1 C
+0.67 C
1955
6.8 C
+1.35 C
1956
5.8 C
+0.30 C
1957
5.6 C
+0.15 C
1958
5.8 C
+0.36 C
1959
5.8 C
+0.29 C
1960
5.5 C
+0.05 C
1961
6.2 C
+0.70 C
1962
5.2 C
-0.24 C
1963
5.7 C
+0.27 C
1964
6.5 C
+1.05 C
1965
4.8 C
-0.68 C
1966
5.2 C
-0.23 C
1967
4.6 C
-0.92 C
1968
5.6 C
+0.10 C
1969
5.2 C
-0.23 C
1970
4.9 C
-0.54 C
1971
4.8 C
-0.69 C
1972
2.8 C
-2.71 C
1973
5.6 C
+0.12 C
1974
4.0 C
-1.46 C
1975
5.3 C
-0.20 C
1976
4.2 C
-1.27 C
The fitted trend in annual mean temperature here over 1902 to 1976 is -0.20 C (-0.40 to 0.01) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.35 F (-0.72 to 0.02) per decade. The slope is a straight line fitted to 37 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Ontonagon
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.20 C (-0.40 to 0.01) per decade
-0.35 F (-0.72 to 0.02) per decade
1902 to 1976
37
Not clearly different from zero
Mean daily maximum
-0.1 C (-0.3 to 0.1) per decade
-0.1 F (-0.5 to 0.2) per decade
1902 to 1976
37
Not clearly different from zero
Mean daily minimum
-0.3 C (-0.5 to -0.1) per decade
-0.6 F (-1.0 to -0.2) per decade
1902 to 1976
37
Fall
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
1900 to 1977
Yearly extremes at Ontonagon: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
38.9 C (102.0 F)
1947
33.9 C (93.0 F)
48
Coldest night (TNn)
-37.8 C (-36.0 F)
1966
-28.0 C (-18.5 F)
48
Wettest day (Rx1day)
81.3 mm (3.2 in)
1955
46.0 mm (1.8 in)
48
Wettest five days (Rx5day)
112.8 mm (4.4 in)
1944
68.9 mm (2.7 in)
48
Longest dry spell (CDD)
52 days
1952
19 days
48
Hottest day (TXx)
The hottest day of the year at Ontonagon, 1900 to 1977. The record is 38.9 C (102.0 F) in 1947, marked on the chart; the median year is 33.9 C (93.0 F).
Hottest day (TXx) at Ontonagon by year
Year
Hottest day (TXx)
1900
36.1 C (97.0 F)
1901
37.2 C (99.0 F)
1902
31.7 C (89.1 F)
1903
34.4 C (93.9 F)
1905
18.3 C (64.9 F)
1913
36.1 C (97.0 F)
1914
33.3 C (91.9 F)
1915
28.9 C (84.0 F)
1938
3.3 C (37.9 F)
1939
35.0 C (95.0 F)
1940
32.2 C (90.0 F)
1941
35.6 C (96.1 F)
1942
34.4 C (93.9 F)
1943
35.0 C (95.0 F)
1944
33.3 C (91.9 F)
1945
36.1 C (97.0 F)
1946
31.7 C (89.1 F)
1947
38.9 C (102.0 F)
1948
35.0 C (95.0 F)
1949
34.4 C (93.9 F)
1950
32.2 C (90.0 F)
1951
31.1 C (88.0 F)
1952
33.3 C (91.9 F)
1953
33.9 C (93.0 F)
1954
31.7 C (89.1 F)
1955
34.4 C (93.9 F)
1956
33.9 C (93.0 F)
1957
33.9 C (93.0 F)
1958
32.8 C (91.0 F)
1959
33.9 C (93.0 F)
1960
33.9 C (93.0 F)
1961
35.0 C (95.0 F)
1962
32.8 C (91.0 F)
1963
33.9 C (93.0 F)
1964
35.0 C (95.0 F)
1965
33.3 C (91.9 F)
1966
34.4 C (93.9 F)
1967
32.2 C (90.0 F)
1968
33.3 C (91.9 F)
1969
35.0 C (95.0 F)
1970
34.4 C (93.9 F)
1971
32.8 C (91.0 F)
1972
31.1 C (88.0 F)
1973
33.3 C (91.9 F)
1974
35.6 C (96.1 F)
1975
36.1 C (97.0 F)
1976
37.2 C (99.0 F)
1977
30.0 C (86.0 F)
Coldest night (TNn)
The coldest night of the year at Ontonagon, 1900 to 1977. The record is -37.8 C (-36.0 F) in 1966, marked on the chart; the median year is -28.0 C (-18.5 F).
Coldest night (TNn) at Ontonagon by year
Year
Coldest night (TNn)
1900
-23.3 C (-9.9 F)
1901
-24.4 C (-11.9 F)
1902
-27.8 C (-18.0 F)
1903
-28.3 C (-18.9 F)
1905
-5.6 C (21.9 F)
1913
-12.2 C (10.0 F)
1914
-28.9 C (-20.0 F)
1915
-34.4 C (-29.9 F)
1938
-22.2 C (-8.0 F)
1939
-33.3 C (-27.9 F)
1940
-23.9 C (-11.0 F)
1941
-20.0 C (-4.0 F)
1942
-26.1 C (-15.0 F)
1943
-28.3 C (-18.9 F)
1944
-23.3 C (-9.9 F)
1945
-26.7 C (-16.1 F)
1946
-26.1 C (-15.0 F)
1947
-25.0 C (-13.0 F)
1948
-30.6 C (-23.1 F)
1949
-22.8 C (-9.0 F)
1950
-28.9 C (-20.0 F)
1951
-33.3 C (-27.9 F)
1952
-24.4 C (-11.9 F)
1953
-23.3 C (-9.9 F)
1954
-28.9 C (-20.0 F)
1955
-22.8 C (-9.0 F)
1956
-25.0 C (-13.0 F)
1957
-25.0 C (-13.0 F)
1958
-28.3 C (-18.9 F)
1959
-31.1 C (-24.0 F)
1960
-25.6 C (-14.1 F)
1961
-28.9 C (-20.0 F)
1962
-34.4 C (-29.9 F)
1963
-35.0 C (-31.0 F)
1964
-22.2 C (-8.0 F)
1965
-31.7 C (-25.1 F)
1966
-37.8 C (-36.0 F)
1967
-36.1 C (-33.0 F)
1968
-28.9 C (-20.0 F)
1969
-25.0 C (-13.0 F)
1970
-33.3 C (-27.9 F)
1971
-31.1 C (-24.0 F)
1972
-31.7 C (-25.1 F)
1973
-29.4 C (-20.9 F)
1974
-28.9 C (-20.0 F)
1975
-24.4 C (-11.9 F)
1976
-25.6 C (-14.1 F)
1977
-30.0 C (-22.0 F)
Wettest day (Rx1day)
The wettest day of the year at Ontonagon, 1900 to 1977. The record is 81.3 mm (3.2 in) in 1955, marked on the chart; the median year is 46.0 mm (1.8 in).
Wettest day (Rx1day) at Ontonagon by year
Year
Wettest day (Rx1day)
1900
39.4 mm (1.6 in)
1901
57.9 mm (2.3 in)
1902
42.2 mm (1.7 in)
1903
58.2 mm (2.3 in)
1905
15.2 mm (0.6 in)
1913
50.8 mm (2.0 in)
1914
50.8 mm (2.0 in)
1915
53.3 mm (2.1 in)
1938
9.7 mm (0.38 in)
1939
68.3 mm (2.7 in)
1940
38.9 mm (1.5 in)
1941
67.8 mm (2.7 in)
1942
54.6 mm (2.1 in)
1943
24.1 mm (0.9 in)
1944
61.0 mm (2.4 in)
1945
39.4 mm (1.6 in)
1946
60.5 mm (2.4 in)
1947
35.6 mm (1.4 in)
1948
31.2 mm (1.2 in)
1949
47.8 mm (1.9 in)
1950
48.3 mm (1.9 in)
1951
46.2 mm (1.8 in)
1952
41.4 mm (1.6 in)
1953
57.9 mm (2.3 in)
1954
50.3 mm (2.0 in)
1955
81.3 mm (3.2 in)
1956
43.2 mm (1.7 in)
1957
32.5 mm (1.3 in)
1958
45.7 mm (1.8 in)
1959
35.6 mm (1.4 in)
1960
40.1 mm (1.6 in)
1961
33.5 mm (1.3 in)
1962
37.1 mm (1.5 in)
1963
33.8 mm (1.3 in)
1964
52.3 mm (2.1 in)
1965
32.3 mm (1.3 in)
1966
47.8 mm (1.9 in)
1967
67.3 mm (2.6 in)
1968
38.6 mm (1.5 in)
1969
76.2 mm (3.0 in)
1970
53.8 mm (2.1 in)
1971
27.9 mm (1.1 in)
1972
57.9 mm (2.3 in)
1973
53.3 mm (2.1 in)
1974
44.5 mm (1.8 in)
1975
53.3 mm (2.1 in)
1976
39.4 mm (1.6 in)
1977
35.6 mm (1.4 in)
Wettest five days (Rx5day)
The wettest five days of the year at Ontonagon, 1900 to 1977. The record is 112.8 mm (4.4 in) in 1944, marked on the chart; the median year is 68.9 mm (2.7 in).
Wettest five days (Rx5day) at Ontonagon by year
Year
Wettest five days (Rx5day)
1900
68.1 mm (2.7 in)
1901
98.3 mm (3.9 in)
1902
59.2 mm (2.3 in)
1903
61.2 mm (2.4 in)
1905
25.4 mm (1.0 in)
1913
86.3 mm (3.4 in)
1914
63.5 mm (2.5 in)
1915
59.7 mm (2.4 in)
1938
23.7 mm (0.9 in)
1939
82.3 mm (3.2 in)
1940
57.2 mm (2.3 in)
1941
27.8 mm (1.1 in)
1942
61.8 mm (2.4 in)
1943
44.7 mm (1.8 in)
1944
112.8 mm (4.4 in)
1945
62.2 mm (2.4 in)
1946
89.2 mm (3.5 in)
1947
72.6 mm (2.9 in)
1948
48.5 mm (1.9 in)
1949
89.2 mm (3.5 in)
1950
61.2 mm (2.4 in)
1951
84.8 mm (3.3 in)
1952
91.6 mm (3.6 in)
1953
103.9 mm (4.1 in)
1954
74.6 mm (2.9 in)
1955
92.5 mm (3.6 in)
1956
76.7 mm (3.0 in)
1957
50.3 mm (2.0 in)
1958
83.1 mm (3.3 in)
1959
64.8 mm (2.6 in)
1960
71.7 mm (2.8 in)
1961
65.7 mm (2.6 in)
1962
71.2 mm (2.8 in)
1963
59.5 mm (2.3 in)
1964
69.8 mm (2.7 in)
1965
58.0 mm (2.3 in)
1966
60.0 mm (2.4 in)
1967
75.1 mm (3.0 in)
1968
60.5 mm (2.4 in)
1969
82.8 mm (3.3 in)
1970
74.4 mm (2.9 in)
1971
64.5 mm (2.5 in)
1972
73.6 mm (2.9 in)
1973
75.2 mm (3.0 in)
1974
89.5 mm (3.5 in)
1975
88.9 mm (3.5 in)
1976
48.8 mm (1.9 in)
1977
61.0 mm (2.4 in)
Longest dry spell (CDD)
The longest dry spell of the year at Ontonagon, 1900 to 1977. The record is 52 days in 1952, marked on the chart; the median year is 19 days.
Longest dry spell (CDD) at Ontonagon by year
Year
Longest dry spell (CDD)
1900
18 days
1901
48 days
1902
19 days
1903
16 days
1905
22 days
1913
31 days
1914
27 days
1915
19 days
1938
11 days
1939
21 days
1940
17 days
1941
13 days
1942
11 days
1943
18 days
1944
20 days
1945
26 days
1946
25 days
1947
24 days
1948
23 days
1949
15 days
1950
14 days
1951
22 days
1952
52 days
1953
19 days
1954
23 days
1955
13 days
1956
15 days
1957
19 days
1958
32 days
1959
12 days
1960
17 days
1961
15 days
1962
16 days
1963
22 days
1964
14 days
1965
16 days
1966
14 days
1967
19 days
1968
18 days
1969
23 days
1970
14 days
1971
23 days
1972
22 days
1973
19 days
1974
14 days
1975
18 days
1976
32 days
1977
12 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
37 years with a frost
Across 37 years with a frost, the median last spring frost at Ontonagon falls on 28 May and the median first autumn frost on 22 September, which leaves a median of 113 days between them.
Fitted over all years, the growing season changes by -5.3 days per decade at this station.
Frost dates and growing season at Ontonagon
Measure
Median, all years
Earliest period
Recent period (1947 to 1976)
Recent against earliest
Fitted trend
Last spring frost
28 May
n/a
29 May
n/a
+1.3 days per decade
First autumn frost
22 September
n/a
22 September
n/a
-4.1 days per decade
Growing days
113 days
n/a
113 days
n/a
-5.3 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
38 years, 1901 to 1976
A day with at least 44.8 mm (1.8 in) of rain is expected about once in 2 years. A day with at least 87.8 mm (3.5 in) of rain is expected about once in 100 years.
Rainfall return levels at Ontonagon: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
44.8 mm (1.8 in)
5 years
57.0 mm (2.2 in)
10 years
64.8 mm (2.6 in)
25 years
74.3 mm (2.9 in)
50 years
81.2 mm (3.2 in)
Longer than the 38 years of record
100 years
87.8 mm (3.5 in)
Longer than the 38 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, 38 years of values from 1901 to 1976.
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: 81.3 mm (3.2 in) in 1955; 76.2 mm (3.0 in) in 1969; 68.3 mm (2.7 in) in 1939.
Download the Data
Data for Ontonagon standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Ontonagon 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 2026-10-16 (16 October 2026). Records are computed by this site and are not official.