Mistassini Post Weather Records (CA007095000)

Record envelope, standing records and threshold days for Mistassini Post (CA007095000), Quebec, Canada, with 96 years of record.

Key Facts for Mistassini Post

Mistassini Post (CA007095000) is a weather station in Quebec, Canada at 50.42 latitude and -73.88 longitude, 380 m (1,247 ft) above sea level.
The station reports from 1885 to 1980, 96 years of record.
1,464 records set at Mistassini Post still stand.
Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
Mistassini Post set a daily record low maximum temperature of -1.0 C (30.2 F) on 14 October 1980.

About the Station

Location: Quebec, Canada, 50.42 latitude, -73.88 longitude.
Elevation: 380 m (1,247 ft).
Period of record: 1885 to 1980, 96 years.
Eligible elements: tmax, tmin, 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 Mistassini Post. 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 Post, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	6.1 C (43.0 F)	-48.9 C (-56.0 F)	n/a	n/a
Feb	8.9 C (48.0 F)	-48.3 C (-54.9 F)	n/a	n/a
Mar	18.3 C (64.9 F)	-42.8 C (-45.0 F)	n/a	n/a
Apr	22.5 C (72.5 F)	-33.9 C (-29.0 F)	n/a	n/a
May	30.0 C (86.0 F)	-17.8 C (0.0 F)	n/a	n/a
Jun	32.8 C (91.0 F)	-6.1 C (21.0 F)	n/a	n/a
Jul	37.8 C (100.0 F)	-4.4 C (24.1 F)	n/a	n/a
Aug	40.6 C (105.1 F)	-4.4 C (24.1 F)	n/a	n/a
Sep	28.3 C (82.9 F)	-8.9 C (16.0 F)	n/a	n/a
Oct	24.4 C (75.9 F)	-13.9 C (7.0 F)	n/a	n/a
Nov	18.3 C (64.9 F)	-35.6 C (-32.1 F)	n/a	n/a
Dec	8.9 C (48.0 F)	-48.9 C (-56.0 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Mistassini Post still stand. 1899 holds the most, with 87.

Standing records at Mistassini Post by the year they were set
Year set	Standing records
1885	20
1898	12
1899	87
1900	14
1914	21
1915	16
1916	33
1917	11
1918	30
1919	32
1920	37
1921	25
1922	24
1923	35
1924	19
1925	22
1926	29
1927	23
1928	17
1929	24
1930	14
1931	17
1932	27
1933	25
1934	14
1935	14
1936	23
1937	13
1938	25
1939	21
1940	16
1941	18
1942	23
1943	8
1944	22
1945	32
1946	14
1947	70
1948	17
1949	13
1950	18
1951	26
1952	10
1953	26
1954	23
1955	10
1956	22
1957	22
1958	24
1959	9
1960	16
1961	12
1962	14
1963	24
1964	19
1965	14
1966	18
1967	11
1968	25
1969	14
1970	16
1971	14
1972	13
1973	14
1974	14
1975	10
1976	14
1977	13
1978	12
1979	23
1980	7

All-Time Record Progression

3 new records

3 all-time records were set at Mistassini Post between 26 June 1944 and 3 August 1945. Each dot is a new record.

When Mistassini Post set new all-time records
Date	Kind	Detail
1944-06-26	Record high minimum temperature	Record high minimum temperature 28.3 C (82.9 F)
1945-07-23	Record high maximum temperature	Record high maximum temperature 37.8 C (100.0 F)
1945-08-03	Record high maximum temperature	Record high maximum temperature 40.6 C (105.1 F)

Wettest Day of Each Month

Aug: 73.4 mm (2.9 in)

The wettest day on record for each calendar month at Mistassini Post. The most was 73.4 mm (2.9 in) on 28 August 1932.

Record daily precipitation for each month at Mistassini Post
Month	Record daily precipitation (mm)	Date
Jan	33.0 mm (1.3 in)	15 January 1953
Feb	30.5 mm (1.2 in)	2 February 1896
Mar	33.0 mm (1.3 in)	13 March 1953
Apr	48.3 mm (1.9 in)	25 April 1945
May	41.9 mm (1.6 in)	18 May 1949
Jun	53.1 mm (2.1 in)	24 June 1979
Jul	61.0 mm (2.4 in)	17 July 1948
Aug	73.4 mm (2.9 in)	28 August 1932
Sep	53.1 mm (2.1 in)	3 September 1918
Oct	50.0 mm (2.0 in)	5 October 1932
Nov	66.0 mm (2.6 in)	30 November 1890
Dec	50.8 mm (2.0 in)	28 December 1969

Period of Record Coverage

1885 to 1980

71 years of record at Mistassini Post, 1885 to 1980. 22 years have data for under 90 percent of days and are left out of rankings: 1885, 1898, 1899, 1900, 1914, 1928, 1933, 1934 and others.

Days with data per year at Mistassini Post
Year	Days with data	Share of year	Complete
1885	199	55%	No
1898	51	14%	No
1899	305	84%	No
1900	187	51%	No
1914	183	50%	No
1915	360	99%	Yes
1916	358	98%	Yes
1917	362	99%	Yes
1918	363	99%	Yes
1919	365	100%	Yes
1920	365	100%	Yes
1921	365	100%	Yes
1922	365	100%	Yes
1923	364	100%	Yes
1924	366	100%	Yes
1925	365	100%	Yes
1926	348	95%	Yes
1927	343	94%	Yes
1928	229	63%	No
1929	332	91%	Yes
1930	361	99%	Yes
1931	365	100%	Yes
1932	366	100%	Yes
1933	311	85%	No
1934	253	69%	No
1935	308	84%	No
1936	364	99%	Yes
1937	354	97%	Yes
1938	359	98%	Yes
1939	351	96%	Yes
1940	359	98%	Yes
1941	333	91%	Yes
1942	365	100%	Yes
1943	223	61%	No
1944	356	97%	Yes
1945	334	92%	Yes
1946	189	52%	No
1947	238	65%	No
1948	365	100%	Yes
1949	273	75%	No
1950	342	94%	Yes
1951	338	93%	Yes
1952	289	79%	No
1953	205	56%	No
1954	365	100%	Yes
1955	261	72%	No
1956	366	100%	Yes
1957	363	99%	Yes
1958	361	99%	Yes
1959	339	93%	Yes
1960	351	96%	Yes
1961	365	100%	Yes
1962	360	99%	Yes
1963	331	91%	Yes
1964	365	100%	Yes
1965	351	96%	Yes
1966	335	92%	Yes
1967	320	88%	No
1968	334	91%	Yes
1969	245	67%	No
1970	325	89%	No
1971	365	100%	Yes
1972	366	100%	Yes
1973	365	100%	Yes
1974	299	82%	No
1975	172	47%	No
1976	365	100%	Yes
1977	357	98%	Yes
1978	365	100%	Yes
1979	346	95%	Yes
1980	183	50%	No

Latest Records

Latest records at Mistassini Post
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
14 October 1980	Mistassini Post, CA	daily low max	-1.0 C (30.2 F)	0.4 C (0.7 F)	41 years	21 of 100 (Routine)
8 October 1980	Mistassini Post, CA	daily rain	10.0 mm (0.4 in)	0.3 mm (0.01 in)	83 years	20 of 100 (Routine)
1 October 1980	Mistassini Post, CA	daily rain	27.0 mm (1.1 in)	4.1 mm (0.16 in)	59 years	32 of 100 (Routine)
29 September 1980	Mistassini Post, CA	daily low max	1.5 C (34.7 F)	0.2 C (0.4 F)	62 years	27 of 100 (Routine)
28 September 1980	Mistassini Post, CA	daily low max	0.5 C (32.9 F)	2.3 C (4.1 F)	45 years	26 of 100 (Routine)
27 September 1980	Mistassini Post, CA	daily low max	1.5 C (34.7 F)	0.7 C (1.3 F)	80 years	34 of 100 (Routine)
27 September 1980	Mistassini Post, CA	daily snowfall	6.5 cm (2.6 in)	4.0 cm (1.6 in)	16 years	21 of 100 (Routine)
1 May 1980	Mistassini Post, CA	daily high max	22.0 C (71.6 F)	0.9 C (1.6 F)	31 years	19 of 100 (Routine)
30 April 1980	Mistassini Post, CA	monthly high max	22.5 C (72.5 F)	1.4 C (2.5 F)	31 years	30 of 100 (Routine)
28 April 1980	Mistassini Post, CA	daily high min	5.0 C (41.0 F)	1.1 C (2.0 F)	80 years	34 of 100 (Routine)
27 November 1979	Mistassini Post, CA	daily high min (Tie)	0.0 C (32.0 F)	tie	28 years	4 of 100 (Routine)
15 November 1979	Mistassini Post, CA	daily low min	-25.0 C (-13.0 F)	2.2 C (4.0 F)	78 years	35 of 100 (Notable)
22 October 1979	Mistassini Post, CA	daily high max	17.2 C (63.0 F)	1.1 C (2.0 F)	20 years	16 of 100 (Routine)
3 October 1979	Mistassini Post, CA	daily rain	24.6 mm (1.0 in)	5.3 mm (0.21 in)	20 years	20 of 100 (Routine)
10 September 1979	Mistassini Post, CA	daily rain	28.2 mm (1.1 in)	6.4 mm (0.25 in)	54 years	33 of 100 (Routine)
2 August 1979	Mistassini Post, CA	daily rain	43.4 mm (1.7 in)	6.3 mm (0.25 in)	34 years	26 of 100 (Routine)
22 July 1979	Mistassini Post, CA	daily low max	13.3 C (55.9 F)	1.7 C (3.1 F)	56 years	28 of 100 (Routine)
17 July 1979	Mistassini Post, CA	daily low min	0.0 C (32.0 F)	1.7 C (3.1 F)	54 years	29 of 100 (Routine)
1 July 1979	Mistassini Post, CA	daily rain	58.4 mm (2.3 in)	24.9 mm (1.0 in)	40 years	51 of 100 (Notable)
24 June 1979	Mistassini Post, CA	monthly rain	53.1 mm (2.1 in)	6.4 mm (0.25 in)	30 years	36 of 100 (Notable)

Climate Trend

37 complete years, 1915 to 1979

One stripe for each of 37 complete years at Mistassini Post, 1915 to 1979. Blue stripes are years cooler than the station's own mean of -1.1 C (30.0 F); red stripes are warmer. The coolest year was 1926, at -3.5 C (25.6 F), and the warmest was 1931, at 0.4 C (32.7 F). The strongest colour marks a difference of 2.5 C (4.5 F).

Annual mean temperature at Mistassini Post as warming stripes, 1915 to 1979
Year	Annual mean temperature	Difference from the station mean
1915	0.4 C	+1.49 C
1916	-0.9 C	+0.21 C
1917	-2.6 C	-1.47 C
1918	-2.3 C	-1.19 C
1919	-1.2 C	-0.06 C
1920	-0.4 C	+0.68 C
1921	-0.6 C	+0.55 C
1922	-1.9 C	-0.74 C
1923	-2.3 C	-1.16 C
1924	-1.3 C	-0.15 C
1925	-1.3 C	-0.22 C
1926	-3.5 C	-2.42 C
1930	-0.6 C	+0.47 C
1931	0.4 C	+1.53 C
1932	-1.7 C	-0.61 C
1936	-2.3 C	-1.19 C
1937	-0.1 C	+1.04 C
1938	-0.9 C	+0.24 C
1939	-2.1 C	-1.03 C
1940	-1.2 C	-0.12 C
1942	0.0 C	+1.15 C
1944	-0.3 C	+0.82 C
1948	-0.8 C	+0.31 C
1954	-0.2 C	+0.88 C
1956	-1.9 C	-0.83 C
1957	-1.1 C	+0.03 C
1959	-1.3 C	-0.18 C
1960	-0.5 C	+0.58 C
1961	-0.1 C	+0.98 C
1962	-1.1 C	+0.05 C
1964	-1.3 C	-0.23 C
1971	-0.9 C	+0.23 C
1972	-2.7 C	-1.63 C
1973	0.4 C	+1.50 C
1977	-0.1 C	+1.02 C
1978	-2.1 C	-1.03 C
1979	-0.5 C	+0.57 C

The fitted trend in annual mean temperature here over 1915 to 1979 is 0.1 C (-0.1 to 0.2) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.1 F (-0.2 to 0.4) 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 Mistassini Post
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.1 C (-0.1 to 0.2) per decade	0.1 F (-0.2 to 0.4) per decade	1915 to 1979	37	Not clearly different from zero
Mean daily maximum	0.0 C (-0.2 to 0.1) per decade	-0.1 F (-0.4 to 0.2) per decade	1915 to 1979	37	Not clearly different from zero
Mean daily minimum	0.20 C (0.01 to 0.39) per decade	0.36 F (0.01 to 0.71) per decade	1915 to 1979	37	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

1885 to 1980

Yearly extremes at Mistassini Post: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	40.6 C (105.1 F)	1945	28.9 C (84.0 F)	71
Coldest night (TNn)	-48.9 C (-56.0 F)	1885	-44.4 C (-47.9 F)	71
Wettest day (Rx1day)	73.4 mm (2.9 in)	1932	34.0 mm (1.3 in)	76
Wettest five days (Rx5day)	121.6 mm (4.8 in)	1932	60.5 mm (2.4 in)	76
Longest dry spell (CDD)	47 days	1899	17 days	76

Hottest day (TXx)

The hottest day of the year at Mistassini Post, 1885 to 1980. The record is 40.6 C (105.1 F) in 1945, marked on the chart; the median year is 28.9 C (84.0 F).

Hottest day (TXx) at Mistassini Post by year
Year	Hottest day (TXx)
1885	29.4 C (84.9 F)
1890	n/a
1891	n/a
1895	n/a
1896	n/a
1897	n/a
1898	8.3 C (46.9 F)
1899	20.0 C (68.0 F)
1900	27.8 C (82.0 F)
1914	30.0 C (86.0 F)
1915	28.9 C (84.0 F)
1916	31.1 C (88.0 F)
1917	27.2 C (81.0 F)
1918	27.8 C (82.0 F)
1919	32.8 C (91.0 F)
1920	30.0 C (86.0 F)
1921	31.1 C (88.0 F)
1922	26.1 C (79.0 F)
1923	30.0 C (86.0 F)
1924	29.4 C (84.9 F)
1925	28.9 C (84.0 F)
1926	31.1 C (88.0 F)
1927	35.0 C (95.0 F)
1928	21.7 C (71.1 F)
1929	26.7 C (80.1 F)
1930	26.7 C (80.1 F)
1931	31.7 C (89.1 F)
1932	28.3 C (82.9 F)
1933	29.4 C (84.9 F)
1934	27.8 C (82.0 F)
1935	30.6 C (87.1 F)
1936	30.0 C (86.0 F)
1937	29.4 C (84.9 F)
1938	29.4 C (84.9 F)
1939	30.0 C (86.0 F)
1940	28.3 C (82.9 F)
1941	30.6 C (87.1 F)
1942	27.2 C (81.0 F)
1943	26.1 C (79.0 F)
1944	33.3 C (91.9 F)
1945	40.6 C (105.1 F)
1946	26.1 C (79.0 F)
1947	33.3 C (91.9 F)
1948	30.0 C (86.0 F)
1949	26.7 C (80.1 F)
1950	28.9 C (84.0 F)
1951	28.9 C (84.0 F)
1952	29.4 C (84.9 F)
1953	27.2 C (81.0 F)
1954	30.0 C (86.0 F)
1955	26.7 C (80.1 F)
1956	25.6 C (78.1 F)
1957	29.4 C (84.9 F)
1958	29.4 C (84.9 F)
1959	30.6 C (87.1 F)
1960	30.0 C (86.0 F)
1961	29.4 C (84.9 F)
1962	28.3 C (82.9 F)
1963	29.4 C (84.9 F)
1964	28.3 C (82.9 F)
1965	27.2 C (81.0 F)
1966	29.4 C (84.9 F)
1967	27.8 C (82.0 F)
1968	27.2 C (81.0 F)
1969	28.3 C (82.9 F)
1970	31.7 C (89.1 F)
1971	25.6 C (78.1 F)
1972	28.9 C (84.0 F)
1973	28.9 C (84.0 F)
1974	27.8 C (82.0 F)
1975	33.3 C (91.9 F)
1976	30.0 C (86.0 F)
1977	27.2 C (81.0 F)
1978	30.0 C (86.0 F)
1979	27.8 C (82.0 F)
1980	24.5 C (76.1 F)

Coldest night (TNn)

The coldest night of the year at Mistassini Post, 1885 to 1980. The record is -48.9 C (-56.0 F) in 1885, marked on the chart; the median year is -44.4 C (-47.9 F).

Coldest night (TNn) at Mistassini Post by year
Year	Coldest night (TNn)
1885	-48.9 C (-56.0 F)
1890	n/a
1891	n/a
1895	n/a
1896	n/a
1897	n/a
1898	-41.1 C (-42.0 F)
1899	-48.3 C (-54.9 F)
1900	-41.7 C (-43.1 F)
1914	-42.8 C (-45.0 F)
1915	-47.8 C (-54.0 F)
1916	-43.3 C (-45.9 F)
1917	-45.6 C (-50.1 F)
1918	-45.0 C (-49.0 F)
1919	-48.9 C (-56.0 F)
1920	-47.8 C (-54.0 F)
1921	-41.1 C (-42.0 F)
1922	-44.4 C (-47.9 F)
1923	-44.4 C (-47.9 F)
1924	-43.3 C (-45.9 F)
1925	-47.8 C (-54.0 F)
1926	-44.4 C (-47.9 F)
1927	-45.0 C (-49.0 F)
1928	-47.8 C (-54.0 F)
1929	-46.1 C (-51.0 F)
1930	-43.3 C (-45.9 F)
1931	-40.6 C (-41.1 F)
1932	-43.9 C (-47.0 F)
1933	-42.8 C (-45.0 F)
1934	-43.9 C (-47.0 F)
1935	-46.7 C (-52.1 F)
1936	-40.6 C (-41.1 F)
1937	-42.8 C (-45.0 F)
1938	-45.0 C (-49.0 F)
1939	-42.2 C (-44.0 F)
1940	-37.8 C (-36.0 F)
1941	-41.7 C (-43.1 F)
1942	-45.0 C (-49.0 F)
1943	-42.8 C (-45.0 F)
1944	-48.3 C (-54.9 F)
1945	-45.0 C (-49.0 F)
1946	-43.9 C (-47.0 F)
1947	-40.0 C (-40.0 F)
1948	-42.8 C (-45.0 F)
1949	-45.0 C (-49.0 F)
1950	-42.8 C (-45.0 F)
1951	-46.1 C (-51.0 F)
1952	-43.9 C (-47.0 F)
1953	-41.1 C (-42.0 F)
1954	-42.8 C (-45.0 F)
1955	-48.3 C (-54.9 F)
1956	-40.0 C (-40.0 F)
1957	-48.9 C (-56.0 F)
1958	-40.0 C (-40.0 F)
1959	-43.9 C (-47.0 F)
1960	-44.4 C (-47.9 F)
1961	-46.7 C (-52.1 F)
1962	-47.8 C (-54.0 F)
1963	-46.7 C (-52.1 F)
1964	-43.3 C (-45.9 F)
1965	-48.3 C (-54.9 F)
1966	-41.1 C (-42.0 F)
1967	-46.7 C (-52.1 F)
1968	-40.0 C (-40.0 F)
1969	-41.7 C (-43.1 F)
1970	-45.6 C (-50.1 F)
1971	-45.6 C (-50.1 F)
1972	-45.6 C (-50.1 F)
1973	-44.4 C (-47.9 F)
1974	-48.9 C (-56.0 F)
1975	-37.2 C (-35.0 F)
1976	-42.8 C (-45.0 F)
1977	-45.6 C (-50.1 F)
1978	-45.6 C (-50.1 F)
1979	-42.8 C (-45.0 F)
1980	-41.0 C (-41.8 F)

Wettest day (Rx1day)

The wettest day of the year at Mistassini Post, 1885 to 1980. The record is 73.4 mm (2.9 in) in 1932, marked on the chart; the median year is 34.0 mm (1.3 in).

Wettest day (Rx1day) at Mistassini Post by year
Year	Wettest day (Rx1day)
1885	15.2 mm (0.6 in)
1890	66.0 mm (2.6 in)
1891	15.2 mm (0.6 in)
1895	21.6 mm (0.9 in)
1896	31.5 mm (1.2 in)
1897	39.1 mm (1.5 in)
1898	35.6 mm (1.4 in)
1899	32.0 mm (1.3 in)
1900	25.4 mm (1.0 in)
1914	25.9 mm (1.0 in)
1915	34.0 mm (1.3 in)
1916	38.1 mm (1.5 in)
1917	36.8 mm (1.4 in)
1918	53.1 mm (2.1 in)
1919	25.4 mm (1.0 in)
1920	25.4 mm (1.0 in)
1921	34.0 mm (1.3 in)
1922	21.1 mm (0.8 in)
1923	29.0 mm (1.1 in)
1924	50.8 mm (2.0 in)
1925	30.5 mm (1.2 in)
1926	30.5 mm (1.2 in)
1927	21.6 mm (0.9 in)
1928	21.6 mm (0.9 in)
1929	28.7 mm (1.1 in)
1930	40.6 mm (1.6 in)
1931	45.2 mm (1.8 in)
1932	73.4 mm (2.9 in)
1933	45.7 mm (1.8 in)
1934	27.2 mm (1.1 in)
1935	37.3 mm (1.5 in)
1936	25.4 mm (1.0 in)
1937	30.5 mm (1.2 in)
1938	45.7 mm (1.8 in)
1939	32.0 mm (1.3 in)
1940	34.3 mm (1.4 in)
1941	30.5 mm (1.2 in)
1942	33.0 mm (1.3 in)
1943	34.3 mm (1.4 in)
1944	42.7 mm (1.7 in)
1945	48.3 mm (1.9 in)
1946	25.4 mm (1.0 in)
1947	57.7 mm (2.3 in)
1948	61.0 mm (2.4 in)
1949	46.7 mm (1.8 in)
1950	22.9 mm (0.9 in)
1951	30.5 mm (1.2 in)
1952	33.5 mm (1.3 in)
1953	39.4 mm (1.6 in)
1954	26.2 mm (1.0 in)
1955	42.7 mm (1.7 in)
1956	38.9 mm (1.5 in)
1957	38.1 mm (1.5 in)
1958	19.1 mm (0.8 in)
1959	27.4 mm (1.1 in)
1960	30.0 mm (1.2 in)
1961	45.2 mm (1.8 in)
1962	22.1 mm (0.9 in)
1963	35.6 mm (1.4 in)
1964	41.4 mm (1.6 in)
1965	41.7 mm (1.6 in)
1966	47.5 mm (1.9 in)
1967	41.1 mm (1.6 in)
1968	26.7 mm (1.1 in)
1969	50.8 mm (2.0 in)
1970	30.5 mm (1.2 in)
1971	39.9 mm (1.6 in)
1972	32.0 mm (1.3 in)
1973	34.8 mm (1.4 in)
1974	38.9 mm (1.5 in)
1975	39.9 mm (1.6 in)
1976	39.9 mm (1.6 in)
1977	25.9 mm (1.0 in)
1978	27.9 mm (1.1 in)
1979	58.4 mm (2.3 in)
1980	27.0 mm (1.1 in)

Wettest five days (Rx5day)

The wettest five days of the year at Mistassini Post, 1885 to 1980. The record is 121.6 mm (4.8 in) in 1932, marked on the chart; the median year is 60.5 mm (2.4 in).

Wettest five days (Rx5day) at Mistassini Post by year
Year	Wettest five days (Rx5day)
1885	22.8 mm (0.9 in)
1890	76.2 mm (3.0 in)
1891	15.2 mm (0.6 in)
1895	23.9 mm (0.9 in)
1896	40.7 mm (1.6 in)
1897	47.0 mm (1.9 in)
1898	55.2 mm (2.2 in)
1899	38.6 mm (1.5 in)
1900	48.3 mm (1.9 in)
1914	39.9 mm (1.6 in)
1915	66.7 mm (2.6 in)
1916	53.4 mm (2.1 in)
1917	55.0 mm (2.2 in)
1918	78.2 mm (3.1 in)
1919	60.2 mm (2.4 in)
1920	50.8 mm (2.0 in)
1921	68.7 mm (2.7 in)
1922	59.5 mm (2.3 in)
1923	36.6 mm (1.4 in)
1924	68.4 mm (2.7 in)
1925	36.9 mm (1.5 in)
1926	66.1 mm (2.6 in)
1927	63.6 mm (2.5 in)
1928	57.1 mm (2.2 in)
1929	72.6 mm (2.9 in)
1930	56.3 mm (2.2 in)
1931	64.8 mm (2.6 in)
1932	121.6 mm (4.8 in)
1933	55.4 mm (2.2 in)
1934	51.1 mm (2.0 in)
1935	89.3 mm (3.5 in)
1936	45.4 mm (1.8 in)
1937	54.4 mm (2.1 in)
1938	61.5 mm (2.4 in)
1939	44.0 mm (1.7 in)
1940	53.5 mm (2.1 in)
1941	36.5 mm (1.4 in)
1942	66.3 mm (2.6 in)
1943	35.3 mm (1.4 in)
1944	76.0 mm (3.0 in)
1945	67.1 mm (2.6 in)
1946	26.2 mm (1.0 in)
1947	57.7 mm (2.3 in)
1948	76.5 mm (3.0 in)
1949	80.2 mm (3.2 in)
1950	36.9 mm (1.5 in)
1951	63.5 mm (2.5 in)
1952	73.4 mm (2.9 in)
1953	70.5 mm (2.8 in)
1954	61.2 mm (2.4 in)
1955	66.0 mm (2.6 in)
1956	69.7 mm (2.7 in)
1957	48.5 mm (1.9 in)
1958	46.2 mm (1.8 in)
1959	38.7 mm (1.5 in)
1960	53.9 mm (2.1 in)
1961	52.8 mm (2.1 in)
1962	55.3 mm (2.2 in)
1963	81.4 mm (3.2 in)
1964	75.6 mm (3.0 in)
1965	99.8 mm (3.9 in)
1966	86.6 mm (3.4 in)
1967	64.2 mm (2.5 in)
1968	60.5 mm (2.4 in)
1969	82.3 mm (3.2 in)
1970	63.5 mm (2.5 in)
1971	68.1 mm (2.7 in)
1972	53.3 mm (2.1 in)
1973	85.6 mm (3.4 in)
1974	77.0 mm (3.0 in)
1975	60.5 mm (2.4 in)
1976	82.4 mm (3.2 in)
1977	58.7 mm (2.3 in)
1978	74.2 mm (2.9 in)
1979	68.6 mm (2.7 in)
1980	63.3 mm (2.5 in)

Longest dry spell (CDD)

The longest dry spell of the year at Mistassini Post, 1885 to 1980. The record is 47 days in 1899, marked on the chart; the median year is 17 days.

Longest dry spell (CDD) at Mistassini Post by year
Year	Longest dry spell (CDD)
1885	21 days
1890	10 days
1891	19 days
1895	15 days
1896	22 days
1897	27 days
1898	22 days
1899	47 days
1900	8 days
1914	10 days
1915	12 days
1916	19 days
1917	11 days
1918	13 days
1919	12 days
1920	16 days
1921	13 days
1922	13 days
1923	17 days
1924	13 days
1925	10 days
1926	26 days
1927	13 days
1928	7 days
1929	25 days
1930	25 days
1931	17 days
1932	15 days
1933	12 days
1934	18 days
1935	21 days
1936	17 days
1937	21 days
1938	12 days
1939	11 days
1940	12 days
1941	14 days
1942	14 days
1943	30 days
1944	26 days
1945	18 days
1946	19 days
1947	18 days
1948	17 days
1949	14 days
1950	39 days
1951	16 days
1952	26 days
1953	13 days
1954	16 days
1955	17 days
1956	23 days
1957	24 days
1958	26 days
1959	15 days
1960	24 days
1961	12 days
1962	16 days
1963	14 days
1964	10 days
1965	17 days
1966	9 days
1967	26 days
1968	13 days
1969	13 days
1970	18 days
1971	17 days
1972	23 days
1973	14 days
1974	13 days
1975	13 days
1976	26 days
1977	28 days
1978	17 days
1979	14 days
1980	40 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 Mistassini Post falls on 13 June and the median first autumn frost on 14 September, which leaves a median of 94 days between them.

Fitted over all years, the growing season changes by +3.4 days per decade at this station.

Frost dates and growing season at Mistassini Post
Measure	Median, all years	Earliest period	Recent period (1922 to 1979)	Recent against earliest	Fitted trend
Last spring frost	13 June	n/a	14 June	n/a	-1.0 days per decade
First autumn frost	14 September	n/a	15 September	n/a	+2.5 days per decade
Growing days	94 days	n/a	94 days	n/a	+3.4 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

44 years, 1896 to 1979

A day with at least 35.0 mm (1.4 in) of rain is expected about once in 2 years. A day with at least 74.5 mm (2.9 in) of rain is expected about once in 100 years.

Rainfall return levels at Mistassini Post: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	35.0 mm (1.4 in)
5 years	44.7 mm (1.8 in)
10 years	51.5 mm (2.0 in)
25 years	60.4 mm (2.4 in)
50 years	67.4 mm (2.7 in)	Longer than the 44 years of record
100 years	74.5 mm (2.9 in)	Longer than the 44 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, 44 years of values from 1896 to 1979.

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: 73.4 mm (2.9 in) in 1932; 61.0 mm (2.4 in) in 1948; 58.4 mm (2.3 in) in 1979.

Download the Data

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

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).