Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Mistassini. 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 Mistassini, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
7.8 C (46.0 F)
-46.1 C (-51.0 F)
n/a
n/a
Feb
8.0 C (46.4 F)
-46.1 C (-51.0 F)
n/a
n/a
Mar
15.6 C (60.1 F)
-38.9 C (-38.0 F)
n/a
n/a
Apr
27.8 C (82.0 F)
-27.8 C (-18.0 F)
n/a
n/a
May
32.8 C (91.0 F)
-11.7 C (10.9 F)
n/a
n/a
Jun
36.1 C (97.0 F)
-2.2 C (28.0 F)
n/a
n/a
Jul
35.6 C (96.1 F)
0.6 C (33.1 F)
n/a
n/a
Aug
36.7 C (98.1 F)
-1.7 C (28.9 F)
n/a
n/a
Sep
31.5 C (88.7 F)
-7.0 C (19.4 F)
n/a
n/a
Oct
26.1 C (79.0 F)
-13.3 C (8.1 F)
n/a
n/a
Nov
17.8 C (64.0 F)
-32.2 C (-26.0 F)
n/a
n/a
Dec
10.5 C (50.9 F)
-45.0 C (-49.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Mistassini still stand. 1913 holds the most, with 70.
Standing records at Mistassini by the year they were set
Year set
Standing records
1912
53
1913
70
1914
70
1915
37
1916
58
1917
46
1918
59
1919
30
1920
56
1921
46
1922
46
1964
53
1965
45
1966
55
1967
32
1968
49
1969
47
1970
33
1971
38
1972
40
1973
35
1974
52
1975
40
1976
44
1977
37
1978
52
1979
55
1980
33
1981
57
1982
46
1983
50
Wettest Day of Each Month
Oct: 88.9 mm (3.5 in)
The wettest day on record for each calendar month at Mistassini. The most was 88.9 mm (3.5 in) on 18 October 1967.
Record daily precipitation for each month at Mistassini
Month
Record daily precipitation (mm)
Date
Jan
38.1 mm (1.5 in)
9 January 1978
Feb
33.5 mm (1.3 in)
3 February 1972
Mar
42.9 mm (1.7 in)
22 March 1972
Apr
32.3 mm (1.3 in)
9 April 1921
May
36.3 mm (1.4 in)
9 May 1964
Jun
62.1 mm (2.4 in)
22 June 1981
Jul
53.5 mm (2.1 in)
20 July 1981
Aug
61.2 mm (2.4 in)
1 August 1973
Sep
68.6 mm (2.7 in)
11 September 1974
Oct
88.9 mm (3.5 in)
18 October 1967
Nov
36.1 mm (1.4 in)
26 November 1972
Dec
35.8 mm (1.4 in)
11 December 1969
Period of Record Coverage
1912 to 1983
Complete yearUnder 90 percent of days
31 years of record at Mistassini, 1912 to 1983. 7 years have data for under 90 percent of days and are left out of rankings: 1919, 1976, 1978, 1980, 1981, 1982, 1983.
Cooler than the station meanWarmer than the station mean
One stripe for each of 25 complete years at Mistassini, 1912 to 1981. Blue stripes are years cooler than the station's own mean of 1.3 C (34.4 F); red stripes are warmer. The coolest year was 1917, at -0.6 C (30.9 F), and the warmest was 1981, at 3.5 C (38.3 F). The strongest colour marks a difference of 2.2 C (4.0 F).
Annual mean temperature at Mistassini as warming stripes, 1912 to 1981
Year
Annual mean temperature
Difference from the station mean
1912
-0.3 C
-1.66 C
1913
1.1 C
-0.20 C
1914
-0.1 C
-1.44 C
1915
2.4 C
+1.08 C
1916
1.0 C
-0.38 C
1917
-0.6 C
-1.93 C
1918
0.0 C
-1.37 C
1920
1.7 C
+0.32 C
1921
1.6 C
+0.30 C
1922
1.3 C
-0.08 C
1964
1.6 C
+0.22 C
1965
0.7 C
-0.64 C
1966
2.7 C
+1.36 C
1967
1.2 C
-0.17 C
1968
1.8 C
+0.47 C
1969
2.4 C
+1.09 C
1970
1.3 C
-0.01 C
1971
1.7 C
+0.33 C
1972
0.2 C
-1.16 C
1973
2.7 C
+1.35 C
1974
0.6 C
-0.77 C
1975
2.0 C
+0.70 C
1976
0.8 C
-0.52 C
1977
2.2 C
+0.83 C
1981
3.5 C
+2.16 C
This station does not have enough complete years (30 are needed) to fit a temperature trend.
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
1912 to 1983
Yearly extremes at Mistassini: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
36.7 C (98.1 F)
1975
31.7 C (89.1 F)
31
Coldest night (TNn)
-46.1 C (-51.0 F)
1972
-41.1 C (-42.0 F)
31
Wettest day (Rx1day)
88.9 mm (3.5 in)
1967
38.1 mm (1.5 in)
31
Wettest five days (Rx5day)
119.6 mm (4.7 in)
1967
64.0 mm (2.5 in)
31
Longest dry spell (CDD)
33 days
1968
14 days
31
Hottest day (TXx)
The hottest day of the year at Mistassini, 1912 to 1983. The record is 36.7 C (98.1 F) in 1975, marked on the chart; the median year is 31.7 C (89.1 F).
Hottest day (TXx) at Mistassini by year
Year
Hottest day (TXx)
1912
35.0 C (95.0 F)
1913
31.1 C (88.0 F)
1914
34.4 C (93.9 F)
1915
30.0 C (86.0 F)
1916
35.0 C (95.0 F)
1917
33.9 C (93.0 F)
1918
31.1 C (88.0 F)
1919
36.1 C (97.0 F)
1920
31.1 C (88.0 F)
1921
35.6 C (96.1 F)
1922
32.8 C (91.0 F)
1964
30.6 C (87.1 F)
1965
31.1 C (88.0 F)
1966
30.6 C (87.1 F)
1967
31.7 C (89.1 F)
1968
32.8 C (91.0 F)
1969
32.2 C (90.0 F)
1970
32.2 C (90.0 F)
1971
31.7 C (89.1 F)
1972
30.6 C (87.1 F)
1973
31.1 C (88.0 F)
1974
30.6 C (87.1 F)
1975
36.7 C (98.1 F)
1976
35.0 C (95.0 F)
1977
31.1 C (88.0 F)
1978
32.8 C (91.0 F)
1979
31.7 C (89.1 F)
1980
30.0 C (86.0 F)
1981
30.5 C (86.9 F)
1982
32.0 C (89.6 F)
1983
34.0 C (93.2 F)
Coldest night (TNn)
The coldest night of the year at Mistassini, 1912 to 1983. The record is -46.1 C (-51.0 F) in 1972, marked on the chart; the median year is -41.1 C (-42.0 F).
Coldest night (TNn) at Mistassini by year
Year
Coldest night (TNn)
1912
-41.7 C (-43.1 F)
1913
-42.2 C (-44.0 F)
1914
-40.6 C (-41.1 F)
1915
-42.2 C (-44.0 F)
1916
-42.8 C (-45.0 F)
1917
-45.0 C (-49.0 F)
1918
-45.0 C (-49.0 F)
1919
-33.9 C (-29.0 F)
1920
-40.6 C (-41.1 F)
1921
-35.0 C (-31.0 F)
1922
-43.3 C (-45.9 F)
1964
-37.8 C (-36.0 F)
1965
-39.4 C (-38.9 F)
1966
-38.3 C (-36.9 F)
1967
-41.7 C (-43.1 F)
1968
-38.3 C (-36.9 F)
1969
-31.1 C (-24.0 F)
1970
-41.1 C (-42.0 F)
1971
-42.8 C (-45.0 F)
1972
-46.1 C (-51.0 F)
1973
-41.1 C (-42.0 F)
1974
-41.1 C (-42.0 F)
1975
-42.8 C (-45.0 F)
1976
-40.0 C (-40.0 F)
1977
-42.2 C (-44.0 F)
1978
-41.1 C (-42.0 F)
1979
-46.1 C (-51.0 F)
1980
-41.0 C (-41.8 F)
1981
-43.0 C (-45.4 F)
1982
-45.0 C (-49.0 F)
1983
-36.5 C (-33.7 F)
Wettest day (Rx1day)
The wettest day of the year at Mistassini, 1912 to 1983. The record is 88.9 mm (3.5 in) in 1967, marked on the chart; the median year is 38.1 mm (1.5 in).
Wettest day (Rx1day) at Mistassini by year
Year
Wettest day (Rx1day)
1912
34.3 mm (1.4 in)
1913
49.8 mm (2.0 in)
1914
40.9 mm (1.6 in)
1915
28.4 mm (1.1 in)
1916
30.7 mm (1.2 in)
1917
38.1 mm (1.5 in)
1918
34.5 mm (1.4 in)
1919
21.6 mm (0.9 in)
1920
33.5 mm (1.3 in)
1921
32.3 mm (1.3 in)
1922
40.1 mm (1.6 in)
1964
42.7 mm (1.7 in)
1965
34.3 mm (1.4 in)
1966
32.3 mm (1.3 in)
1967
88.9 mm (3.5 in)
1968
35.8 mm (1.4 in)
1969
35.8 mm (1.4 in)
1970
53.3 mm (2.1 in)
1971
45.0 mm (1.8 in)
1972
42.9 mm (1.7 in)
1973
62.2 mm (2.4 in)
1974
68.6 mm (2.7 in)
1975
33.8 mm (1.3 in)
1976
41.7 mm (1.6 in)
1977
42.2 mm (1.7 in)
1978
38.1 mm (1.5 in)
1979
41.9 mm (1.6 in)
1980
52.3 mm (2.1 in)
1981
62.1 mm (2.4 in)
1982
20.0 mm (0.8 in)
1983
26.0 mm (1.0 in)
Wettest five days (Rx5day)
The wettest five days of the year at Mistassini, 1912 to 1983. The record is 119.6 mm (4.7 in) in 1967, marked on the chart; the median year is 64.0 mm (2.5 in).
Wettest five days (Rx5day) at Mistassini by year
Year
Wettest five days (Rx5day)
1912
68.1 mm (2.7 in)
1913
74.5 mm (2.9 in)
1914
74.7 mm (2.9 in)
1915
46.4 mm (1.8 in)
1916
39.1 mm (1.5 in)
1917
56.4 mm (2.2 in)
1918
63.2 mm (2.5 in)
1919
53.3 mm (2.1 in)
1920
53.1 mm (2.1 in)
1921
55.5 mm (2.2 in)
1922
70.3 mm (2.8 in)
1964
68.1 mm (2.7 in)
1965
57.9 mm (2.3 in)
1966
64.0 mm (2.5 in)
1967
119.6 mm (4.7 in)
1968
54.8 mm (2.2 in)
1969
53.6 mm (2.1 in)
1970
82.2 mm (3.2 in)
1971
62.8 mm (2.5 in)
1972
65.3 mm (2.6 in)
1973
88.4 mm (3.5 in)
1974
89.4 mm (3.5 in)
1975
56.2 mm (2.2 in)
1976
69.3 mm (2.7 in)
1977
46.0 mm (1.8 in)
1978
70.3 mm (2.8 in)
1979
64.3 mm (2.5 in)
1980
68.2 mm (2.7 in)
1981
73.1 mm (2.9 in)
1982
45.4 mm (1.8 in)
1983
45.4 mm (1.8 in)
Longest dry spell (CDD)
The longest dry spell of the year at Mistassini, 1912 to 1983. The record is 33 days in 1968, marked on the chart; the median year is 14 days.
Longest dry spell (CDD) at Mistassini by year
Year
Longest dry spell (CDD)
1912
13 days
1913
16 days
1914
18 days
1915
13 days
1916
18 days
1917
14 days
1918
14 days
1919
11 days
1920
11 days
1921
14 days
1922
13 days
1964
14 days
1965
28 days
1966
16 days
1967
13 days
1968
33 days
1969
15 days
1970
13 days
1971
16 days
1972
27 days
1973
12 days
1974
10 days
1975
18 days
1976
12 days
1977
12 days
1978
23 days
1979
22 days
1980
25 days
1981
12 days
1982
18 days
1983
22 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
25 years with a frost
Across 25 years with a frost, the median last spring frost at Mistassini falls on 29 May and the median first autumn frost on 13 September, which leaves a median of 107 days between them.
Fitted over all years, the growing season changes by -0.5 days per decade at this station.
Frost dates and growing season at Mistassini
Measure
Median, all years
Earliest period
Recent period (1912 to 1981)
Recent against earliest
Fitted trend
Last spring frost
29 May
n/a
29 May
n/a
+0.1 days per decade
First autumn frost
13 September
n/a
13 September
n/a
-0.3 days per decade
Growing days
107 days
n/a
107 days
n/a
-0.5 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.
Download the Data
Data for Mistassini standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Mistassini 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.