Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Portage des Roches. 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 Portage des Roches, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
12.8 C (55.0 F)
-42.8 C (-45.0 F)
n/a
n/a
Feb
13.5 C (56.3 F)
-42.8 C (-45.0 F)
n/a
n/a
Mar
21.1 C (70.0 F)
-35.6 C (-32.1 F)
n/a
n/a
Apr
28.3 C (82.9 F)
-23.9 C (-11.0 F)
n/a
n/a
May
33.3 C (91.9 F)
-11.1 C (12.0 F)
n/a
n/a
Jun
34.4 C (93.9 F)
-6.7 C (19.9 F)
n/a
n/a
Jul
35.6 C (96.1 F)
0.6 C (33.1 F)
n/a
n/a
Aug
35.6 C (96.1 F)
-1.1 C (30.0 F)
n/a
n/a
Sep
33.3 C (91.9 F)
-7.8 C (18.0 F)
n/a
n/a
Oct
28.3 C (82.9 F)
-12.2 C (10.0 F)
n/a
n/a
Nov
22.2 C (72.0 F)
-30.6 C (-23.1 F)
n/a
n/a
Dec
16.1 C (61.0 F)
-40.0 C (-40.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Portage des Roches still stand. 1947 holds the most, with 49.
Standing records at Portage des Roches by the year they were set
Year set
Standing records
1926
32
1927
22
1928
29
1929
25
1930
24
1931
13
1932
26
1933
48
1934
35
1935
23
1936
31
1937
20
1938
28
1939
27
1940
18
1941
16
1942
30
1943
26
1944
36
1945
34
1946
37
1947
49
1948
30
1949
45
1950
27
1951
27
1952
19
1953
34
1954
20
1955
22
1956
22
1957
28
1958
9
1959
25
1960
14
1961
22
1962
24
1963
23
1964
23
1965
16
1966
25
1967
18
1968
24
1969
15
1970
24
1971
14
1972
20
1973
22
1974
32
1975
17
1976
27
1977
20
1978
18
1979
35
1980
21
1981
24
1982
30
1983
19
All-Time Record Progression
1 new records
1 all-time records were set at Portage des Roches between 23 March 1968 and 23 March 1968. Each dot is a new record.
When Portage des Roches set new all-time records
Date
Kind
Detail
1968-03-23
Record daily snowfall
Record daily snowfall 35.8 cm (14.1 in)
Wettest Day of Each Month
Sep: 85.3 mm (3.4 in)
The wettest day on record for each calendar month at Portage des Roches. The most was 85.3 mm (3.4 in) on 30 September 1946.
Record daily precipitation for each month at Portage des Roches
Month
Record daily precipitation (mm)
Date
Jan
35.6 mm (1.4 in)
26 January 1928
Feb
30.5 mm (1.2 in)
19 February 1972
Mar
35.8 mm (1.4 in)
23 March 1968
Apr
38.9 mm (1.5 in)
27 April 1938
May
52.1 mm (2.1 in)
27 May 1939
Jun
79.5 mm (3.1 in)
21 June 1972
Jul
49.5 mm (1.9 in)
14 July 1962
Aug
60.5 mm (2.4 in)
12 August 1937
Sep
85.3 mm (3.4 in)
30 September 1946
Oct
60.7 mm (2.4 in)
7 October 1932
Nov
47.4 mm (1.9 in)
4 November 1982
Dec
37.3 mm (1.5 in)
4 December 1950
Period of Record Coverage
1926 to 1983
Complete yearUnder 90 percent of days
58 years of record at Portage des Roches, 1926 to 1983. Every year has data for at least 90 percent of its days.
Cooler than the station meanWarmer than the station mean
One stripe for each of 57 complete years at Portage des Roches, 1926 to 1983. Blue stripes are years cooler than the station's own mean of 2.0 C (35.6 F); red stripes are warmer. The coolest year was 1934, at -0.1 C (31.8 F), and the warmest was 1953, at 3.9 C (39.1 F). The strongest colour marks a difference of 2.1 C (3.8 F).
Annual mean temperature at Portage des Roches as warming stripes, 1926 to 1983
Year
Annual mean temperature
Difference from the station mean
1926
0.3 C
-1.65 C
1927
1.6 C
-0.37 C
1928
0.7 C
-1.32 C
1929
0.3 C
-1.68 C
1930
1.8 C
-0.14 C
1931
2.7 C
+0.76 C
1932
1.1 C
-0.91 C
1933
0.4 C
-1.63 C
1934
-0.1 C
-2.07 C
1935
0.7 C
-1.30 C
1936
0.5 C
-1.50 C
1937
2.4 C
+0.40 C
1938
1.7 C
-0.27 C
1939
0.4 C
-1.55 C
1940
0.8 C
-1.17 C
1941
1.4 C
-0.56 C
1942
1.7 C
-0.30 C
1943
1.1 C
-0.92 C
1944
3.2 C
+1.24 C
1945
2.5 C
+0.54 C
1946
1.9 C
-0.04 C
1947
2.3 C
+0.30 C
1948
2.2 C
+0.19 C
1949
3.8 C
+1.81 C
1950
2.8 C
+0.78 C
1951
2.9 C
+0.94 C
1952
3.4 C
+1.45 C
1953
3.9 C
+1.94 C
1954
2.5 C
+0.50 C
1955
2.9 C
+0.92 C
1956
1.7 C
-0.31 C
1957
2.5 C
+0.53 C
1958
2.6 C
+0.60 C
1959
2.4 C
+0.46 C
1960
3.8 C
+1.85 C
1961
3.5 C
+1.49 C
1962
1.8 C
-0.17 C
1963
2.0 C
+0.05 C
1964
2.2 C
+0.18 C
1965
1.2 C
-0.74 C
1966
3.2 C
+1.21 C
1967
1.8 C
-0.18 C
1968
2.1 C
+0.14 C
1969
2.8 C
+0.77 C
1970
1.8 C
-0.14 C
1972
0.7 C
-1.25 C
1973
3.2 C
+1.18 C
1974
1.2 C
-0.80 C
1975
2.4 C
+0.45 C
1976
1.2 C
-0.83 C
1977
2.7 C
+0.73 C
1978
1.2 C
-0.75 C
1979
2.9 C
+0.91 C
1980
1.1 C
-0.86 C
1981
3.0 C
+1.06 C
1982
1.3 C
-0.70 C
1983
2.6 C
+0.63 C
The annual mean temperature here has risen by 0.2 C (0.1 to 0.4) per decade over 1926 to 1983. In Fahrenheit: 0.4 F (0.1 to 0.6) per decade. The slope is a straight line fitted to 57 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Portage des Roches
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.2 C (0.1 to 0.4) per decade
0.4 F (0.1 to 0.6) per decade
1926 to 1983
57
Rise
Mean daily maximum
0.20 C (0.02 to 0.38) per decade
0.36 F (0.04 to 0.68) per decade
1926 to 1983
57
Rise
Mean daily minimum
0.2 C (0.1 to 0.4) per decade
0.4 F (0.1 to 0.6) per decade
1926 to 1983
57
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
1926 to 1983
Yearly extremes at Portage des Roches: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
35.6 C (96.1 F)
1935
32.8 C (91.0 F)
58
Coldest night (TNn)
-42.8 C (-45.0 F)
1946
-37.5 C (-35.5 F)
58
Wettest day (Rx1day)
85.3 mm (3.4 in)
1946
41.1 mm (1.6 in)
58
Wettest five days (Rx5day)
143.8 mm (5.7 in)
1942
66.9 mm (2.6 in)
58
Longest dry spell (CDD)
25 days
1958
12 days
58
Hottest day (TXx)
The hottest day of the year at Portage des Roches, 1926 to 1983. The record is 35.6 C (96.1 F) in 1935, marked on the chart; the median year is 32.8 C (91.0 F).
Hottest day (TXx) at Portage des Roches by year
Year
Hottest day (TXx)
1926
34.4 C (93.9 F)
1927
31.7 C (89.1 F)
1928
33.9 C (93.0 F)
1929
32.8 C (91.0 F)
1930
30.0 C (86.0 F)
1931
32.2 C (90.0 F)
1932
31.1 C (88.0 F)
1933
33.3 C (91.9 F)
1934
31.7 C (89.1 F)
1935
35.6 C (96.1 F)
1936
31.1 C (88.0 F)
1937
34.4 C (93.9 F)
1938
32.8 C (91.0 F)
1939
32.8 C (91.0 F)
1940
30.0 C (86.0 F)
1941
34.4 C (93.9 F)
1942
31.7 C (89.1 F)
1943
32.8 C (91.0 F)
1944
34.4 C (93.9 F)
1945
31.7 C (89.1 F)
1946
32.8 C (91.0 F)
1947
33.3 C (91.9 F)
1948
31.7 C (89.1 F)
1949
35.6 C (96.1 F)
1950
33.3 C (91.9 F)
1951
31.7 C (89.1 F)
1952
35.0 C (95.0 F)
1953
35.0 C (95.0 F)
1954
31.7 C (89.1 F)
1955
35.0 C (95.0 F)
1956
30.6 C (87.1 F)
1957
32.8 C (91.0 F)
1958
29.4 C (84.9 F)
1959
33.3 C (91.9 F)
1960
32.2 C (90.0 F)
1961
33.3 C (91.9 F)
1962
30.0 C (86.0 F)
1963
32.8 C (91.0 F)
1964
29.4 C (84.9 F)
1965
32.8 C (91.0 F)
1966
31.1 C (88.0 F)
1967
33.3 C (91.9 F)
1968
33.3 C (91.9 F)
1969
33.3 C (91.9 F)
1970
31.7 C (89.1 F)
1971
31.7 C (89.1 F)
1972
31.7 C (89.1 F)
1973
31.7 C (89.1 F)
1974
32.8 C (91.0 F)
1975
35.6 C (96.1 F)
1976
33.3 C (91.9 F)
1977
32.2 C (90.0 F)
1978
33.3 C (91.9 F)
1979
32.8 C (91.0 F)
1980
31.0 C (87.8 F)
1981
30.5 C (86.9 F)
1982
33.5 C (92.3 F)
1983
34.0 C (93.2 F)
Coldest night (TNn)
The coldest night of the year at Portage des Roches, 1926 to 1983. The record is -42.8 C (-45.0 F) in 1946, marked on the chart; the median year is -37.5 C (-35.5 F).
Coldest night (TNn) at Portage des Roches by year
Year
Coldest night (TNn)
1926
-30.6 C (-23.1 F)
1927
-34.4 C (-29.9 F)
1928
-35.0 C (-31.0 F)
1929
-36.7 C (-34.1 F)
1930
-33.9 C (-29.0 F)
1931
-33.9 C (-29.0 F)
1932
-33.3 C (-27.9 F)
1933
-38.9 C (-38.0 F)
1934
-37.8 C (-36.0 F)
1935
-37.2 C (-35.0 F)
1936
-32.2 C (-26.0 F)
1937
-33.3 C (-27.9 F)
1938
-35.6 C (-32.1 F)
1939
-34.4 C (-29.9 F)
1940
-33.9 C (-29.0 F)
1941
-36.7 C (-34.1 F)
1942
-37.2 C (-35.0 F)
1943
-37.8 C (-36.0 F)
1944
-40.0 C (-40.0 F)
1945
-41.1 C (-42.0 F)
1946
-42.8 C (-45.0 F)
1947
-40.6 C (-41.1 F)
1948
-38.3 C (-36.9 F)
1949
-35.0 C (-31.0 F)
1950
-38.3 C (-36.9 F)
1951
-42.2 C (-44.0 F)
1952
-40.6 C (-41.1 F)
1953
-34.4 C (-29.9 F)
1954
-42.2 C (-44.0 F)
1955
-42.8 C (-45.0 F)
1956
-32.2 C (-26.0 F)
1957
-41.1 C (-42.0 F)
1958
-36.1 C (-33.0 F)
1959
-38.3 C (-36.9 F)
1960
-36.7 C (-34.1 F)
1961
-39.4 C (-38.9 F)
1962
-40.0 C (-40.0 F)
1963
-34.4 C (-29.9 F)
1964
-31.1 C (-24.0 F)
1965
-37.2 C (-35.0 F)
1966
-35.0 C (-31.0 F)
1967
-40.0 C (-40.0 F)
1968
-34.4 C (-29.9 F)
1969
-30.0 C (-22.0 F)
1970
-38.9 C (-38.0 F)
1971
-38.9 C (-38.0 F)
1972
-38.9 C (-38.0 F)
1973
-41.1 C (-42.0 F)
1974
-41.7 C (-43.1 F)
1975
-38.3 C (-36.9 F)
1976
-40.0 C (-40.0 F)
1977
-37.8 C (-36.0 F)
1978
-34.4 C (-29.9 F)
1979
-40.0 C (-40.0 F)
1980
-38.5 C (-37.3 F)
1981
-36.0 C (-32.8 F)
1982
-39.5 C (-39.1 F)
1983
-34.5 C (-30.1 F)
Wettest day (Rx1day)
The wettest day of the year at Portage des Roches, 1926 to 1983. The record is 85.3 mm (3.4 in) in 1946, marked on the chart; the median year is 41.1 mm (1.6 in).
Wettest day (Rx1day) at Portage des Roches by year
Year
Wettest day (Rx1day)
1926
45.0 mm (1.8 in)
1927
29.2 mm (1.1 in)
1928
53.1 mm (2.1 in)
1929
43.4 mm (1.7 in)
1930
46.5 mm (1.8 in)
1931
31.0 mm (1.2 in)
1932
60.7 mm (2.4 in)
1933
31.2 mm (1.2 in)
1934
59.7 mm (2.4 in)
1935
39.4 mm (1.6 in)
1936
41.9 mm (1.6 in)
1937
60.5 mm (2.4 in)
1938
45.7 mm (1.8 in)
1939
52.1 mm (2.1 in)
1940
36.6 mm (1.4 in)
1941
34.5 mm (1.4 in)
1942
54.1 mm (2.1 in)
1943
39.4 mm (1.6 in)
1944
28.7 mm (1.1 in)
1945
29.5 mm (1.2 in)
1946
85.3 mm (3.4 in)
1947
40.4 mm (1.6 in)
1948
50.8 mm (2.0 in)
1949
42.9 mm (1.7 in)
1950
44.2 mm (1.7 in)
1951
34.3 mm (1.4 in)
1952
56.4 mm (2.2 in)
1953
29.2 mm (1.1 in)
1954
35.3 mm (1.4 in)
1955
39.9 mm (1.6 in)
1956
40.1 mm (1.6 in)
1957
27.4 mm (1.1 in)
1958
41.7 mm (1.6 in)
1959
41.9 mm (1.6 in)
1960
52.3 mm (2.1 in)
1961
33.5 mm (1.3 in)
1962
49.5 mm (1.9 in)
1963
39.6 mm (1.6 in)
1964
51.8 mm (2.0 in)
1965
22.6 mm (0.9 in)
1966
69.6 mm (2.7 in)
1967
30.5 mm (1.2 in)
1968
42.9 mm (1.7 in)
1969
35.3 mm (1.4 in)
1970
56.4 mm (2.2 in)
1971
57.4 mm (2.3 in)
1972
79.5 mm (3.1 in)
1973
32.8 mm (1.3 in)
1974
25.4 mm (1.0 in)
1975
30.7 mm (1.2 in)
1976
51.1 mm (2.0 in)
1977
45.7 mm (1.8 in)
1978
38.1 mm (1.5 in)
1979
40.4 mm (1.6 in)
1980
39.4 mm (1.6 in)
1981
35.6 mm (1.4 in)
1982
47.4 mm (1.9 in)
1983
37.4 mm (1.5 in)
Wettest five days (Rx5day)
The wettest five days of the year at Portage des Roches, 1926 to 1983. The record is 143.8 mm (5.7 in) in 1942, marked on the chart; the median year is 66.9 mm (2.6 in).
Wettest five days (Rx5day) at Portage des Roches by year
Year
Wettest five days (Rx5day)
1926
55.4 mm (2.2 in)
1927
72.2 mm (2.8 in)
1928
75.7 mm (3.0 in)
1929
65.8 mm (2.6 in)
1930
74.1 mm (2.9 in)
1931
66.8 mm (2.6 in)
1932
78.4 mm (3.1 in)
1933
51.3 mm (2.0 in)
1934
81.1 mm (3.2 in)
1935
66.0 mm (2.6 in)
1936
66.0 mm (2.6 in)
1937
126.0 mm (5.0 in)
1938
63.3 mm (2.5 in)
1939
67.1 mm (2.6 in)
1940
59.5 mm (2.3 in)
1941
54.0 mm (2.1 in)
1942
143.8 mm (5.7 in)
1943
65.0 mm (2.6 in)
1944
47.2 mm (1.9 in)
1945
47.8 mm (1.9 in)
1946
111.2 mm (4.4 in)
1947
71.7 mm (2.8 in)
1948
76.9 mm (3.0 in)
1949
76.8 mm (3.0 in)
1950
63.5 mm (2.5 in)
1951
50.8 mm (2.0 in)
1952
107.7 mm (4.2 in)
1953
54.1 mm (2.1 in)
1954
52.6 mm (2.1 in)
1955
71.9 mm (2.8 in)
1956
56.9 mm (2.2 in)
1957
50.2 mm (2.0 in)
1958
72.9 mm (2.9 in)
1959
59.7 mm (2.4 in)
1960
79.5 mm (3.1 in)
1961
65.5 mm (2.6 in)
1962
65.8 mm (2.6 in)
1963
66.3 mm (2.6 in)
1964
68.3 mm (2.7 in)
1965
59.0 mm (2.3 in)
1966
111.0 mm (4.4 in)
1967
55.4 mm (2.2 in)
1968
84.8 mm (3.3 in)
1969
54.9 mm (2.2 in)
1970
83.2 mm (3.3 in)
1971
100.1 mm (3.9 in)
1972
81.8 mm (3.2 in)
1973
67.1 mm (2.6 in)
1974
61.6 mm (2.4 in)
1975
59.2 mm (2.3 in)
1976
73.9 mm (2.9 in)
1977
75.1 mm (3.0 in)
1978
71.4 mm (2.8 in)
1979
56.7 mm (2.2 in)
1980
64.2 mm (2.5 in)
1981
81.8 mm (3.2 in)
1982
91.0 mm (3.6 in)
1983
77.4 mm (3.0 in)
Longest dry spell (CDD)
The longest dry spell of the year at Portage des Roches, 1926 to 1983. The record is 25 days in 1958, marked on the chart; the median year is 12 days.
Longest dry spell (CDD) at Portage des Roches by year
Year
Longest dry spell (CDD)
1926
14 days
1927
11 days
1928
12 days
1929
8 days
1930
14 days
1931
15 days
1932
11 days
1933
10 days
1934
8 days
1935
23 days
1936
9 days
1937
20 days
1938
10 days
1939
12 days
1940
14 days
1941
9 days
1942
12 days
1943
10 days
1944
17 days
1945
10 days
1946
9 days
1947
11 days
1948
16 days
1949
12 days
1950
12 days
1951
9 days
1952
15 days
1953
19 days
1954
15 days
1955
15 days
1956
12 days
1957
19 days
1958
25 days
1959
12 days
1960
19 days
1961
19 days
1962
17 days
1963
10 days
1964
14 days
1965
16 days
1966
10 days
1967
13 days
1968
13 days
1969
15 days
1970
12 days
1971
10 days
1972
9 days
1973
9 days
1974
9 days
1975
13 days
1976
15 days
1977
10 days
1978
13 days
1979
14 days
1980
12 days
1981
12 days
1982
12 days
1983
11 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
57 years with a frost
Across 57 years with a frost, the median last spring frost at Portage des Roches falls on 5 June and the median first autumn frost on 14 September, which leaves a median of 99 days between them.
Fitted over all years, the growing season changes by +1.0 days per decade at this station.
Frost dates and growing season at Portage des Roches
Measure
Median, all years
Earliest period
Recent period (1953 to 1983)
Recent against earliest
Fitted trend
Last spring frost
5 June
n/a
5 June
n/a
-0.4 days per decade
First autumn frost
14 September
n/a
16 September
n/a
+0.6 days per decade
Growing days
99 days
n/a
103 days
n/a
+1.0 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
58 years, 1926 to 1983
A day with at least 41.2 mm (1.6 in) of rain is expected about once in 2 years. A day with at least 83.9 mm (3.3 in) of rain is expected about once in 100 years.
Rainfall return levels at Portage des Roches: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
41.2 mm (1.6 in)
5 years
52.4 mm (2.1 in)
10 years
59.9 mm (2.4 in)
25 years
69.5 mm (2.7 in)
50 years
76.7 mm (3.0 in)
100 years
83.9 mm (3.3 in)
Longer than the 58 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, 58 years of values from 1926 to 1983.
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: 85.3 mm (3.4 in) in 1946; 79.5 mm (3.1 in) in 1972; 69.6 mm (2.7 in) in 1966.
Station Changes
2 suspected
2 changes were suspected in the annual mean temperature of Portage des Roches, at 1943 and 1962. Each is measured against neighbouring stations.
Relative to 5 neighbouring stations, the station's annual mean temperature from 1943 ran 0.8 C (1.5 F) higher than in the years before (likely change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 1962 ran 0.3 C (0.5 F) lower than in the years before (possible change).
Suspected changes in the annual mean temperature at Portage des Roches, against neighbouring stations
Year
Shift (C)
Shift (F)
Strength
Neighbours
1943
+0.8
+1.5
likely
5
1962
-0.3
-0.5
possible
5
Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.
Download the Data
Data for Portage des Roches standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Portage des Roches 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 2026-10-15 (15 October 2026). Records are computed by this site and are not official.