Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Lac Onatchiway. 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 Lac Onatchiway, 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)
-47.8 C (-54.0 F)
n/a
n/a
Feb
11.7 C (53.1 F)
-45.6 C (-50.1 F)
n/a
n/a
Mar
18.9 C (66.0 F)
-40.0 C (-40.0 F)
n/a
n/a
Apr
28.9 C (84.0 F)
-27.2 C (-17.0 F)
n/a
n/a
May
31.7 C (89.1 F)
-14.4 C (6.1 F)
n/a
n/a
Jun
32.2 C (90.0 F)
-7.8 C (18.0 F)
n/a
n/a
Jul
34.4 C (93.9 F)
-1.7 C (28.9 F)
n/a
n/a
Aug
33.9 C (93.0 F)
-5.0 C (23.0 F)
n/a
n/a
Sep
30.6 C (87.1 F)
-11.7 C (10.9 F)
n/a
n/a
Oct
26.1 C (79.0 F)
-15.0 C (5.0 F)
n/a
n/a
Nov
21.1 C (70.0 F)
-32.2 C (-26.0 F)
n/a
n/a
Dec
15.6 C (60.1 F)
-43.9 C (-47.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Lac Onatchiway still stand. 1933 holds the most, with 62.
Standing records at Lac Onatchiway by the year they were set
Year set
Standing records
1920
22
1921
27
1922
45
1923
49
1924
31
1925
57
1926
43
1927
31
1928
28
1929
44
1930
34
1931
23
1932
39
1933
62
1934
39
1935
20
1936
48
1937
35
1938
41
1939
34
1940
28
1941
19
1942
34
1943
26
1944
25
1945
32
1946
31
1947
38
1948
17
1949
29
1950
39
1951
29
1952
18
1953
34
1954
34
1955
18
1956
31
1957
26
1958
17
1959
30
1960
23
1961
19
1962
14
1963
15
1964
21
1965
27
1966
29
1967
8
1968
1
Wettest Day of Each Month
Dec: 77.5 mm (3.1 in)
The wettest day on record for each calendar month at Lac Onatchiway. The most was 77.5 mm (3.1 in) on 22 December 1942.
Record daily precipitation for each month at Lac Onatchiway
Month
Record daily precipitation (mm)
Date
Jan
56.6 mm (2.2 in)
7 January 1947
Feb
54.9 mm (2.2 in)
15 February 1954
Mar
38.1 mm (1.5 in)
26 March 1928
Apr
35.6 mm (1.4 in)
8 April 1940
May
66.0 mm (2.6 in)
20 May 1923
Jun
58.4 mm (2.3 in)
14 June 1949
Jul
64.3 mm (2.5 in)
12 July 1944
Aug
58.7 mm (2.3 in)
9 August 1980
Sep
57.7 mm (2.3 in)
23 September 1966
Oct
48.3 mm (1.9 in)
27 October 1920
Nov
61.0 mm (2.4 in)
19 November 1928
Dec
77.5 mm (3.1 in)
22 December 1942
Period of Record Coverage
1920 to 1968
Complete yearUnder 90 percent of days
49 years of record at Lac Onatchiway, 1920 to 1968. 8 years have data for under 90 percent of days and are left out of rankings: 1920, 1921, 1963, 1964, 1965, 1966, 1967, 1968.
Cooler than the station meanWarmer than the station mean
One stripe for each of 36 complete years at Lac Onatchiway, 1922 to 1961. Blue stripes are years cooler than the station's own mean of 0.6 C (33.0 F); red stripes are warmer. The coolest year was 1926, at -1.7 C (29.0 F), and the warmest was 1931, at 2.4 C (36.3 F). The strongest colour marks a difference of 2.3 C (4.1 F).
Annual mean temperature at Lac Onatchiway as warming stripes, 1922 to 1961
Year
Annual mean temperature
Difference from the station mean
1922
0.2 C
-0.34 C
1923
-0.7 C
-1.30 C
1924
-0.5 C
-1.10 C
1925
1.2 C
+0.60 C
1926
-1.7 C
-2.24 C
1927
0.3 C
-0.24 C
1929
-0.9 C
-1.44 C
1930
0.8 C
+0.23 C
1931
2.4 C
+1.82 C
1932
0.5 C
-0.12 C
1933
0.0 C
-0.60 C
1934
-0.2 C
-0.76 C
1935
0.0 C
-0.53 C
1936
-0.1 C
-0.64 C
1937
2.0 C
+1.40 C
1938
1.3 C
+0.75 C
1939
0.0 C
-0.58 C
1940
0.7 C
+0.11 C
1941
1.0 C
+0.45 C
1942
1.1 C
+0.52 C
1943
-0.6 C
-1.21 C
1944
1.0 C
+0.38 C
1945
1.0 C
+0.45 C
1946
-0.4 C
-0.98 C
1948
1.0 C
+0.41 C
1949
1.3 C
+0.69 C
1950
0.6 C
+0.04 C
1953
2.3 C
+1.75 C
1954
0.8 C
+0.22 C
1955
1.1 C
+0.53 C
1956
-0.2 C
-0.76 C
1957
1.0 C
+0.41 C
1958
0.9 C
+0.36 C
1959
0.2 C
-0.35 C
1960
1.4 C
+0.87 C
1961
1.7 C
+1.17 C
The annual mean temperature here has risen by 0.3 C (0.1 to 0.6) per decade over 1922 to 1961. In Fahrenheit: 0.6 F (0.1 to 1.0) per decade. The slope is a straight line fitted to 36 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Lac Onatchiway
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.3 C (0.1 to 0.6) per decade
0.6 F (0.1 to 1.0) per decade
1922 to 1961
36
Rise
Mean daily maximum
0.5 C (0.2 to 0.7) per decade
0.8 F (0.4 to 1.2) per decade
1922 to 1961
36
Rise
Mean daily minimum
0.2 C (-0.2 to 0.5) per decade
0.3 F (-0.3 to 0.9) per decade
1922 to 1961
36
Not clearly different from zero
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
1920 to 1981
Yearly extremes at Lac Onatchiway: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
34.4 C (93.9 F)
1939
31.7 C (89.1 F)
49
Coldest night (TNn)
-47.8 C (-54.0 F)
1925
-41.1 C (-42.0 F)
47
Wettest day (Rx1day)
77.5 mm (3.1 in)
1942
43.4 mm (1.7 in)
58
Wettest five days (Rx5day)
132.1 mm (5.2 in)
1923
73.6 mm (2.9 in)
58
Longest dry spell (CDD)
35 days
1958
13 days
58
Hottest day (TXx)
The hottest day of the year at Lac Onatchiway, 1920 to 1981. The record is 34.4 C (93.9 F) in 1939, marked on the chart; the median year is 31.7 C (89.1 F).
Hottest day (TXx) at Lac Onatchiway by year
Year
Hottest day (TXx)
1920
29.4 C (84.9 F)
1921
32.8 C (91.0 F)
1922
29.4 C (84.9 F)
1923
32.2 C (90.0 F)
1924
27.8 C (82.0 F)
1925
28.9 C (84.0 F)
1926
33.3 C (91.9 F)
1927
33.3 C (91.9 F)
1928
32.2 C (90.0 F)
1929
31.7 C (89.1 F)
1930
30.6 C (87.1 F)
1931
30.6 C (87.1 F)
1932
30.6 C (87.1 F)
1933
32.2 C (90.0 F)
1934
29.4 C (84.9 F)
1935
33.9 C (93.0 F)
1936
30.6 C (87.1 F)
1937
32.2 C (90.0 F)
1938
32.2 C (90.0 F)
1939
34.4 C (93.9 F)
1940
29.4 C (84.9 F)
1941
32.2 C (90.0 F)
1942
30.6 C (87.1 F)
1943
32.8 C (91.0 F)
1944
32.8 C (91.0 F)
1945
32.2 C (90.0 F)
1946
31.1 C (88.0 F)
1947
32.2 C (90.0 F)
1948
30.6 C (87.1 F)
1949
31.7 C (89.1 F)
1950
31.7 C (89.1 F)
1951
32.2 C (90.0 F)
1952
33.3 C (91.9 F)
1953
34.4 C (93.9 F)
1954
30.0 C (86.0 F)
1955
32.2 C (90.0 F)
1956
30.6 C (87.1 F)
1957
29.4 C (84.9 F)
1958
27.8 C (82.0 F)
1959
31.1 C (88.0 F)
1960
31.7 C (89.1 F)
1961
30.0 C (86.0 F)
1962
28.9 C (84.0 F)
1963
31.7 C (89.1 F)
1964
29.4 C (84.9 F)
1965
30.0 C (86.0 F)
1966
29.4 C (84.9 F)
1967
33.3 C (91.9 F)
1968
0.6 C (33.1 F)
1973
n/a
1974
n/a
1975
n/a
1976
n/a
1977
n/a
1978
n/a
1979
n/a
1980
n/a
1981
n/a
Coldest night (TNn)
The coldest night of the year at Lac Onatchiway, 1920 to 1981. The record is -47.8 C (-54.0 F) in 1925, marked on the chart; the median year is -41.1 C (-42.0 F).
Coldest night (TNn) at Lac Onatchiway by year
Year
Coldest night (TNn)
1920
-42.2 C (-44.0 F)
1921
-41.7 C (-43.1 F)
1922
-44.4 C (-47.9 F)
1923
-43.9 C (-47.0 F)
1924
-42.8 C (-45.0 F)
1925
-47.8 C (-54.0 F)
1926
-42.8 C (-45.0 F)
1927
-42.8 C (-45.0 F)
1928
-40.0 C (-40.0 F)
1929
-45.0 C (-49.0 F)
1930
-39.4 C (-38.9 F)
1931
-40.0 C (-40.0 F)
1932
-40.0 C (-40.0 F)
1933
-43.9 C (-47.0 F)
1934
-44.4 C (-47.9 F)
1935
-41.1 C (-42.0 F)
1936
-37.2 C (-35.0 F)
1937
-40.0 C (-40.0 F)
1938
-40.0 C (-40.0 F)
1939
-38.9 C (-38.0 F)
1940
-35.6 C (-32.1 F)
1941
-38.3 C (-36.9 F)
1942
-40.6 C (-41.1 F)
1943
-40.0 C (-40.0 F)
1944
-40.6 C (-41.1 F)
1945
-41.1 C (-42.0 F)
1946
-41.1 C (-42.0 F)
1947
-40.0 C (-40.0 F)
1948
-41.7 C (-43.1 F)
1949
-40.0 C (-40.0 F)
1950
-42.2 C (-44.0 F)
1951
-43.9 C (-47.0 F)
1952
-43.9 C (-47.0 F)
1953
-37.2 C (-35.0 F)
1954
-44.4 C (-47.9 F)
1955
-45.6 C (-50.1 F)
1956
-38.3 C (-36.9 F)
1957
-45.6 C (-50.1 F)
1958
-39.4 C (-38.9 F)
1959
-43.3 C (-45.9 F)
1960
-41.1 C (-42.0 F)
1961
-41.7 C (-43.1 F)
1962
-44.4 C (-47.9 F)
1963
-38.9 C (-38.0 F)
1964
-33.3 C (-27.9 F)
1965
-38.9 C (-38.0 F)
1966
-37.2 C (-35.0 F)
1967
n/a
1968
n/a
1973
n/a
1974
n/a
1975
n/a
1976
n/a
1977
n/a
1978
n/a
1979
n/a
1980
n/a
1981
n/a
Wettest day (Rx1day)
The wettest day of the year at Lac Onatchiway, 1920 to 1981. The record is 77.5 mm (3.1 in) in 1942, marked on the chart; the median year is 43.4 mm (1.7 in).
Wettest day (Rx1day) at Lac Onatchiway by year
Year
Wettest day (Rx1day)
1920
48.3 mm (1.9 in)
1921
28.4 mm (1.1 in)
1922
32.5 mm (1.3 in)
1923
66.0 mm (2.6 in)
1924
49.5 mm (1.9 in)
1925
53.3 mm (2.1 in)
1926
35.6 mm (1.4 in)
1927
33.0 mm (1.3 in)
1928
61.0 mm (2.4 in)
1929
47.5 mm (1.9 in)
1930
32.5 mm (1.3 in)
1931
45.2 mm (1.8 in)
1932
54.1 mm (2.1 in)
1933
43.2 mm (1.7 in)
1934
55.9 mm (2.2 in)
1935
36.6 mm (1.4 in)
1936
43.4 mm (1.7 in)
1937
38.6 mm (1.5 in)
1938
30.5 mm (1.2 in)
1939
36.1 mm (1.4 in)
1940
55.9 mm (2.2 in)
1941
43.4 mm (1.7 in)
1942
77.5 mm (3.1 in)
1943
40.1 mm (1.6 in)
1944
64.3 mm (2.5 in)
1945
41.1 mm (1.6 in)
1946
52.3 mm (2.1 in)
1947
56.6 mm (2.2 in)
1948
53.6 mm (2.1 in)
1949
58.4 mm (2.3 in)
1950
57.7 mm (2.3 in)
1951
33.0 mm (1.3 in)
1952
44.5 mm (1.8 in)
1953
38.4 mm (1.5 in)
1954
54.9 mm (2.2 in)
1955
48.0 mm (1.9 in)
1956
54.9 mm (2.2 in)
1957
34.3 mm (1.4 in)
1958
42.7 mm (1.7 in)
1959
46.5 mm (1.8 in)
1960
38.9 mm (1.5 in)
1961
37.3 mm (1.5 in)
1962
34.3 mm (1.4 in)
1963
40.1 mm (1.6 in)
1964
45.2 mm (1.8 in)
1965
33.8 mm (1.3 in)
1966
57.7 mm (2.3 in)
1967
29.7 mm (1.2 in)
1968
10.2 mm (0.4 in)
1973
38.6 mm (1.5 in)
1974
26.2 mm (1.0 in)
1975
32.0 mm (1.3 in)
1976
45.7 mm (1.8 in)
1977
33.8 mm (1.3 in)
1978
35.6 mm (1.4 in)
1979
57.2 mm (2.3 in)
1980
58.7 mm (2.3 in)
1981
47.3 mm (1.9 in)
Wettest five days (Rx5day)
The wettest five days of the year at Lac Onatchiway, 1920 to 1981. The record is 132.1 mm (5.2 in) in 1923, marked on the chart; the median year is 73.6 mm (2.9 in).
Wettest five days (Rx5day) at Lac Onatchiway by year
Year
Wettest five days (Rx5day)
1920
65.8 mm (2.6 in)
1921
68.6 mm (2.7 in)
1922
58.5 mm (2.3 in)
1923
132.1 mm (5.2 in)
1924
101.6 mm (4.0 in)
1925
70.8 mm (2.8 in)
1926
71.2 mm (2.8 in)
1927
94.5 mm (3.7 in)
1928
79.2 mm (3.1 in)
1929
71.1 mm (2.8 in)
1930
77.8 mm (3.1 in)
1931
76.2 mm (3.0 in)
1932
114.1 mm (4.5 in)
1933
56.9 mm (2.2 in)
1934
87.3 mm (3.4 in)
1935
67.6 mm (2.7 in)
1936
70.6 mm (2.8 in)
1937
67.3 mm (2.6 in)
1938
54.6 mm (2.1 in)
1939
82.5 mm (3.2 in)
1940
95.4 mm (3.8 in)
1941
82.8 mm (3.3 in)
1942
108.4 mm (4.3 in)
1943
85.1 mm (3.4 in)
1944
77.8 mm (3.1 in)
1945
89.1 mm (3.5 in)
1946
90.4 mm (3.6 in)
1947
107.4 mm (4.2 in)
1948
79.7 mm (3.1 in)
1949
100.0 mm (3.9 in)
1950
93.6 mm (3.7 in)
1951
73.5 mm (2.9 in)
1952
58.7 mm (2.3 in)
1953
83.3 mm (3.3 in)
1954
64.8 mm (2.6 in)
1955
73.6 mm (2.9 in)
1956
76.2 mm (3.0 in)
1957
66.5 mm (2.6 in)
1958
74.5 mm (2.9 in)
1959
58.7 mm (2.3 in)
1960
71.3 mm (2.8 in)
1961
73.3 mm (2.9 in)
1962
54.0 mm (2.1 in)
1963
72.3 mm (2.8 in)
1964
80.8 mm (3.2 in)
1965
49.3 mm (1.9 in)
1966
95.2 mm (3.7 in)
1967
61.1 mm (2.4 in)
1968
16.6 mm (0.7 in)
1973
63.8 mm (2.5 in)
1974
65.6 mm (2.6 in)
1975
75.3 mm (3.0 in)
1976
65.8 mm (2.6 in)
1977
49.3 mm (1.9 in)
1978
52.6 mm (2.1 in)
1979
77.9 mm (3.1 in)
1980
107.8 mm (4.2 in)
1981
61.3 mm (2.4 in)
Longest dry spell (CDD)
The longest dry spell of the year at Lac Onatchiway, 1920 to 1981. The record is 35 days in 1958, marked on the chart; the median year is 13 days.
Longest dry spell (CDD) at Lac Onatchiway by year
Year
Longest dry spell (CDD)
1920
13 days
1921
18 days
1922
17 days
1923
18 days
1924
18 days
1925
15 days
1926
14 days
1927
22 days
1928
13 days
1929
19 days
1930
14 days
1931
23 days
1932
13 days
1933
13 days
1934
9 days
1935
10 days
1936
9 days
1937
22 days
1938
10 days
1939
12 days
1940
22 days
1941
16 days
1942
12 days
1943
10 days
1944
15 days
1945
9 days
1946
8 days
1947
10 days
1948
10 days
1949
10 days
1950
14 days
1951
12 days
1952
11 days
1953
13 days
1954
14 days
1955
16 days
1956
11 days
1957
17 days
1958
35 days
1959
9 days
1960
16 days
1961
20 days
1962
18 days
1963
11 days
1964
9 days
1965
11 days
1966
13 days
1967
15 days
1968
15 days
1973
8 days
1974
7 days
1975
18 days
1976
11 days
1977
7 days
1978
6 days
1979
9 days
1980
8 days
1981
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
36 years with a frost
Across 36 years with a frost, the median last spring frost at Lac Onatchiway falls on 14 June and the median first autumn frost on 27 August, which leaves a median of 80 days between them.
Fitted over all years, the growing season changes by +1.6 days per decade at this station.
Frost dates and growing season at Lac Onatchiway
Measure
Median, all years
Earliest period
Recent period (1929 to 1961)
Recent against earliest
Fitted trend
Last spring frost
14 June
n/a
13 June
n/a
+0.1 days per decade
First autumn frost
27 August
n/a
1 September
n/a
+1.7 days per decade
Growing days
80 days
n/a
82 days
n/a
+1.6 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
39 years, 1922 to 1966
A day with at least 45.4 mm (1.8 in) of rain is expected about once in 2 years. A day with at least 79.1 mm (3.1 in) of rain is expected about once in 100 years.
Rainfall return levels at Lac Onatchiway: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
45.4 mm (1.8 in)
5 years
55.7 mm (2.2 in)
10 years
62.0 mm (2.4 in)
25 years
69.3 mm (2.7 in)
50 years
74.4 mm (2.9 in)
Longer than the 39 years of record
100 years
79.1 mm (3.1 in)
Longer than the 39 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, 39 years of values from 1922 to 1966.
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: 77.5 mm (3.1 in) in 1942; 66.0 mm (2.6 in) in 1923; 64.3 mm (2.5 in) in 1944.
Download the Data
Data for Lac Onatchiway standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Lac Onatchiway 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.