Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Lethbridge A. 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 Lethbridge A, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
16.7 C (62.1 F)
-42.8 C (-45.0 F)
n/a
n/a
Feb
18.9 C (66.0 F)
-42.2 C (-44.0 F)
n/a
n/a
Mar
23.3 C (73.9 F)
-37.8 C (-36.0 F)
n/a
n/a
Apr
31.1 C (88.0 F)
-25.6 C (-14.1 F)
n/a
n/a
May
32.8 C (91.0 F)
-11.7 C (10.9 F)
n/a
n/a
Jun
38.3 C (100.9 F)
-1.7 C (28.9 F)
n/a
n/a
Jul
39.4 C (102.9 F)
1.7 C (35.1 F)
n/a
n/a
Aug
38.3 C (100.9 F)
0.0 C (32.0 F)
n/a
n/a
Sep
36.7 C (98.1 F)
-9.4 C (15.1 F)
n/a
n/a
Oct
31.7 C (89.1 F)
-21.7 C (-7.1 F)
n/a
n/a
Nov
22.8 C (73.0 F)
-33.9 C (-29.0 F)
n/a
n/a
Dec
18.3 C (64.9 F)
-42.8 C (-45.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Lethbridge A still stand. 1939 holds the most, with 70.
Standing records at Lethbridge A by the year they were set
Year set
Standing records
1938
31
1939
70
1940
40
1941
31
1942
42
1943
55
1944
21
1945
17
1946
34
1947
27
1948
16
1949
38
1950
42
1951
68
1952
26
1953
32
1954
56
1955
41
1956
29
1957
30
1958
29
1959
23
1960
20
1961
37
1962
30
1963
38
1964
27
1965
36
1966
23
1967
34
1968
44
1969
40
1970
24
1971
30
1972
38
1973
21
1974
14
1975
31
1976
15
1977
33
1978
15
1979
20
1980
30
1981
21
1982
16
1983
29
All-Time Record Progression
3 new records
3 all-time records were set at Lethbridge A between 21 September 1968 and 23 May 1980. Each dot is a new record.
When Lethbridge A set new all-time records
Date
Kind
Detail
1968-09-21
Record daily snowfall
Record daily snowfall 55.1 cm (21.7 in)
1973-07-10
Record high maximum temperature
Record high maximum temperature 39.4 C (102.9 F)
1980-05-23
Record daily precipitation
Record daily precipitation 85.4 mm (3.4 in)
Wettest Day of Each Month
May: 85.4 mm (3.4 in)
The wettest day on record for each calendar month at Lethbridge A. The most was 85.4 mm (3.4 in) on 23 May 1980.
Record daily precipitation for each month at Lethbridge A
Month
Record daily precipitation (mm)
Date
Jan
18.8 mm (0.7 in)
7 January 1949
Feb
24.4 mm (1.0 in)
22 February 1953
Mar
30.7 mm (1.2 in)
25 March 1972
Apr
54.6 mm (2.1 in)
27 April 1974
May
85.4 mm (3.4 in)
23 May 1980
Jun
71.9 mm (2.8 in)
22 June 1963
Jul
63.5 mm (2.5 in)
1 July 1982
Aug
68.6 mm (2.7 in)
22 August 1978
Sep
49.3 mm (1.9 in)
21 September 1968
Oct
39.1 mm (1.5 in)
2 October 1946
Nov
37.8 mm (1.5 in)
1 November 1944
Dec
21.6 mm (0.9 in)
7 December 1945
Period of Record Coverage
1938 to 1983
Complete yearUnder 90 percent of days
46 years of record at Lethbridge A, 1938 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 46 complete years at Lethbridge A, 1938 to 1983. Blue stripes are years cooler than the station's own mean of 5.4 C (41.7 F); red stripes are warmer. The coolest year was 1951, at 2.9 C (37.1 F), and the warmest was 1981, at 7.1 C (44.8 F). The strongest colour marks a difference of 2.6 C (4.7 F).
Annual mean temperature at Lethbridge A as warming stripes, 1938 to 1983
Year
Annual mean temperature
Difference from the station mean
1938
6.3 C
+0.89 C
1939
6.9 C
+1.47 C
1940
5.8 C
+0.44 C
1941
6.7 C
+1.30 C
1942
5.8 C
+0.35 C
1943
6.1 C
+0.67 C
1944
6.6 C
+1.20 C
1945
4.7 C
-0.66 C
1946
5.9 C
+0.51 C
1947
5.4 C
+0.03 C
1948
5.1 C
-0.34 C
1949
4.6 C
-0.80 C
1950
3.7 C
-1.71 C
1951
2.9 C
-2.55 C
1952
5.9 C
+0.51 C
1953
6.6 C
+1.16 C
1954
5.2 C
-0.21 C
1955
3.3 C
-2.07 C
1956
5.1 C
-0.27 C
1957
5.4 C
-0.01 C
1958
6.6 C
+1.15 C
1959
5.2 C
-0.19 C
1960
6.0 C
+0.58 C
1961
6.7 C
+1.26 C
1962
6.2 C
+0.78 C
1963
6.7 C
+1.25 C
1964
5.1 C
-0.33 C
1965
4.4 C
-1.01 C
1966
4.8 C
-0.59 C
1967
5.3 C
-0.06 C
1968
4.9 C
-0.50 C
1969
4.2 C
-1.18 C
1970
5.1 C
-0.27 C
1971
5.0 C
-0.38 C
1972
4.0 C
-1.40 C
1973
5.8 C
+0.44 C
1974
6.3 C
+0.94 C
1975
4.2 C
-1.19 C
1976
6.8 C
+1.37 C
1977
5.6 C
+0.21 C
1978
3.9 C
-1.46 C
1979
5.2 C
-0.24 C
1980
5.6 C
+0.23 C
1981
7.1 C
+1.72 C
1982
3.7 C
-1.67 C
1983
5.8 C
+0.41 C
The fitted trend in annual mean temperature here over 1938 to 1983 is -0.1 C (-0.4 to 0.1) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.2 F (-0.6 to 0.2) per decade. The slope is a straight line fitted to 46 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Lethbridge A
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.1 C (-0.4 to 0.1) per decade
-0.2 F (-0.6 to 0.2) per decade
1938 to 1983
46
Not clearly different from zero
Mean daily maximum
-0.1 C (-0.3 to 0.2) per decade
-0.1 F (-0.6 to 0.4) per decade
1938 to 1983
46
Not clearly different from zero
Mean daily minimum
-0.19 C (-0.40 to 0.03) per decade
-0.33 F (-0.71 to 0.05) per decade
1938 to 1983
46
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
1938 to 1983
Yearly extremes at Lethbridge A: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
39.4 C (102.9 F)
1973
35.6 C (96.1 F)
46
Coldest night (TNn)
-42.8 C (-45.0 F)
1950
-34.7 C (-30.5 F)
46
Wettest day (Rx1day)
85.4 mm (3.4 in)
1980
37.2 mm (1.5 in)
46
Wettest five days (Rx5day)
112.1 mm (4.4 in)
1968
64.9 mm (2.6 in)
46
Longest dry spell (CDD)
55 days
1954
32 days
46
Hottest day (TXx)
The hottest day of the year at Lethbridge A, 1938 to 1983. The record is 39.4 C (102.9 F) in 1973, marked on the chart; the median year is 35.6 C (96.1 F).
Hottest day (TXx) at Lethbridge A by year
Year
Hottest day (TXx)
1938
37.2 C (99.0 F)
1939
38.9 C (102.0 F)
1940
37.2 C (99.0 F)
1941
38.3 C (100.9 F)
1942
33.3 C (91.9 F)
1943
34.4 C (93.9 F)
1944
35.6 C (96.1 F)
1945
36.1 C (97.0 F)
1946
35.6 C (96.1 F)
1947
34.4 C (93.9 F)
1948
33.3 C (91.9 F)
1949
35.6 C (96.1 F)
1950
36.7 C (98.1 F)
1951
33.9 C (93.0 F)
1952
33.3 C (91.9 F)
1953
36.1 C (97.0 F)
1954
35.0 C (95.0 F)
1955
34.4 C (93.9 F)
1956
34.4 C (93.9 F)
1957
33.9 C (93.0 F)
1958
34.4 C (93.9 F)
1959
35.6 C (96.1 F)
1960
38.9 C (102.0 F)
1961
38.3 C (100.9 F)
1962
35.6 C (96.1 F)
1963
32.8 C (91.0 F)
1964
36.1 C (97.0 F)
1965
34.4 C (93.9 F)
1966
33.3 C (91.9 F)
1967
36.7 C (98.1 F)
1968
36.1 C (97.0 F)
1969
36.7 C (98.1 F)
1970
35.6 C (96.1 F)
1971
36.7 C (98.1 F)
1972
34.4 C (93.9 F)
1973
39.4 C (102.9 F)
1974
35.0 C (95.0 F)
1975
36.1 C (97.0 F)
1976
34.4 C (93.9 F)
1977
32.6 C (90.7 F)
1978
33.3 C (91.9 F)
1979
35.7 C (96.3 F)
1980
33.7 C (92.7 F)
1981
35.1 C (95.2 F)
1982
32.7 C (90.9 F)
1983
37.6 C (99.7 F)
Coldest night (TNn)
The coldest night of the year at Lethbridge A, 1938 to 1983. The record is -42.8 C (-45.0 F) in 1950, marked on the chart; the median year is -34.7 C (-30.5 F).
Coldest night (TNn) at Lethbridge A by year
Year
Coldest night (TNn)
1938
-35.0 C (-31.0 F)
1939
-42.2 C (-44.0 F)
1940
-31.7 C (-25.1 F)
1941
-30.0 C (-22.0 F)
1942
-32.8 C (-27.0 F)
1943
-42.2 C (-44.0 F)
1944
-27.8 C (-18.0 F)
1945
-30.0 C (-22.0 F)
1946
-31.7 C (-25.1 F)
1947
-37.8 C (-36.0 F)
1948
-33.9 C (-29.0 F)
1949
-37.8 C (-36.0 F)
1950
-42.8 C (-45.0 F)
1951
-37.8 C (-36.0 F)
1952
-33.9 C (-29.0 F)
1953
-27.8 C (-18.0 F)
1954
-42.8 C (-45.0 F)
1955
-34.4 C (-29.9 F)
1956
-35.0 C (-31.0 F)
1957
-40.6 C (-41.1 F)
1958
-31.1 C (-24.0 F)
1959
-31.7 C (-25.1 F)
1960
-35.0 C (-31.0 F)
1961
-31.7 C (-25.1 F)
1962
-32.2 C (-26.0 F)
1963
-35.6 C (-32.1 F)
1964
-35.6 C (-32.1 F)
1965
-33.3 C (-27.9 F)
1966
-32.2 C (-26.0 F)
1967
-32.8 C (-27.0 F)
1968
-42.8 C (-45.0 F)
1969
-42.8 C (-45.0 F)
1970
-37.8 C (-36.0 F)
1971
-38.3 C (-36.9 F)
1972
-38.3 C (-36.9 F)
1973
-31.7 C (-25.1 F)
1974
-37.2 C (-35.0 F)
1975
-33.9 C (-29.0 F)
1976
-31.1 C (-24.0 F)
1977
-37.2 C (-35.0 F)
1978
-33.3 C (-27.9 F)
1979
-36.3 C (-33.3 F)
1980
-33.3 C (-27.9 F)
1981
-31.3 C (-24.3 F)
1982
-35.6 C (-32.1 F)
1983
-39.2 C (-38.6 F)
Wettest day (Rx1day)
The wettest day of the year at Lethbridge A, 1938 to 1983. The record is 85.4 mm (3.4 in) in 1980, marked on the chart; the median year is 37.2 mm (1.5 in).
Wettest day (Rx1day) at Lethbridge A by year
Year
Wettest day (Rx1day)
1938
35.6 mm (1.4 in)
1939
35.1 mm (1.4 in)
1940
29.5 mm (1.2 in)
1941
40.6 mm (1.6 in)
1942
39.1 mm (1.5 in)
1943
16.8 mm (0.7 in)
1944
37.8 mm (1.5 in)
1945
30.0 mm (1.2 in)
1946
52.3 mm (2.1 in)
1947
54.6 mm (2.1 in)
1948
36.1 mm (1.4 in)
1949
48.0 mm (1.9 in)
1950
16.5 mm (0.6 in)
1951
61.7 mm (2.4 in)
1952
23.1 mm (0.9 in)
1953
49.8 mm (2.0 in)
1954
24.1 mm (0.9 in)
1955
40.6 mm (1.6 in)
1956
35.1 mm (1.4 in)
1957
40.6 mm (1.6 in)
1958
29.0 mm (1.1 in)
1959
58.7 mm (2.3 in)
1960
16.8 mm (0.7 in)
1961
19.1 mm (0.8 in)
1962
23.6 mm (0.9 in)
1963
71.9 mm (2.8 in)
1964
36.6 mm (1.4 in)
1965
35.6 mm (1.4 in)
1966
47.8 mm (1.9 in)
1967
40.4 mm (1.6 in)
1968
49.3 mm (1.9 in)
1969
23.1 mm (0.9 in)
1970
48.3 mm (1.9 in)
1971
30.7 mm (1.2 in)
1972
30.7 mm (1.2 in)
1973
34.3 mm (1.4 in)
1974
54.6 mm (2.1 in)
1975
39.6 mm (1.6 in)
1976
27.2 mm (1.1 in)
1977
25.0 mm (1.0 in)
1978
68.6 mm (2.7 in)
1979
60.1 mm (2.4 in)
1980
85.4 mm (3.4 in)
1981
62.1 mm (2.4 in)
1982
63.5 mm (2.5 in)
1983
20.4 mm (0.8 in)
Wettest five days (Rx5day)
The wettest five days of the year at Lethbridge A, 1938 to 1983. The record is 112.1 mm (4.4 in) in 1968, marked on the chart; the median year is 64.9 mm (2.6 in).
Wettest five days (Rx5day) at Lethbridge A by year
Year
Wettest five days (Rx5day)
1938
41.7 mm (1.6 in)
1939
75.0 mm (3.0 in)
1940
53.8 mm (2.1 in)
1941
68.3 mm (2.7 in)
1942
66.5 mm (2.6 in)
1943
20.1 mm (0.8 in)
1944
63.8 mm (2.5 in)
1945
57.1 mm (2.2 in)
1946
70.3 mm (2.8 in)
1947
88.7 mm (3.5 in)
1948
58.7 mm (2.3 in)
1949
60.0 mm (2.4 in)
1950
21.9 mm (0.9 in)
1951
87.5 mm (3.4 in)
1952
38.9 mm (1.5 in)
1953
82.3 mm (3.2 in)
1954
49.0 mm (1.9 in)
1955
80.4 mm (3.2 in)
1956
62.5 mm (2.5 in)
1957
45.7 mm (1.8 in)
1958
32.9 mm (1.3 in)
1959
87.0 mm (3.4 in)
1960
40.7 mm (1.6 in)
1961
38.4 mm (1.5 in)
1962
30.7 mm (1.2 in)
1963
106.7 mm (4.2 in)
1964
88.4 mm (3.5 in)
1965
77.9 mm (3.1 in)
1966
72.4 mm (2.9 in)
1967
69.2 mm (2.7 in)
1968
112.1 mm (4.4 in)
1969
46.1 mm (1.8 in)
1970
66.1 mm (2.6 in)
1971
47.2 mm (1.9 in)
1972
44.4 mm (1.7 in)
1973
38.4 mm (1.5 in)
1974
83.5 mm (3.3 in)
1975
68.3 mm (2.7 in)
1976
47.6 mm (1.9 in)
1977
39.0 mm (1.5 in)
1978
87.7 mm (3.5 in)
1979
70.9 mm (2.8 in)
1980
108.2 mm (4.3 in)
1981
84.1 mm (3.3 in)
1982
80.4 mm (3.2 in)
1983
40.6 mm (1.6 in)
Longest dry spell (CDD)
The longest dry spell of the year at Lethbridge A, 1938 to 1983. The record is 55 days in 1954, marked on the chart; the median year is 32 days.
Longest dry spell (CDD) at Lethbridge A by year
Year
Longest dry spell (CDD)
1938
35 days
1939
41 days
1940
26 days
1941
24 days
1942
22 days
1943
37 days
1944
32 days
1945
26 days
1946
35 days
1947
24 days
1948
44 days
1949
39 days
1950
28 days
1951
29 days
1952
38 days
1953
28 days
1954
55 days
1955
32 days
1956
23 days
1957
22 days
1958
25 days
1959
26 days
1960
42 days
1961
28 days
1962
34 days
1963
50 days
1964
30 days
1965
43 days
1966
19 days
1967
36 days
1968
54 days
1969
48 days
1970
31 days
1971
19 days
1972
33 days
1973
32 days
1974
41 days
1975
17 days
1976
39 days
1977
28 days
1978
35 days
1979
30 days
1980
24 days
1981
35 days
1982
21 days
1983
23 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
46 years with a frost
Across 46 years with a frost, the median last spring frost at Lethbridge A falls on 17 May and the median first autumn frost on 19 September, which leaves a median of 124 days between them.
Fitted over all years, the growing season changes by +2.8 days per decade at this station.
Frost dates and growing season at Lethbridge A
Measure
Median, all years
Earliest period
Recent period (1954 to 1983)
Recent against earliest
Fitted trend
Last spring frost
17 May
n/a
14 May
n/a
-2.5 days per decade
First autumn frost
19 September
n/a
19 September
n/a
+0.3 days per decade
Growing days
124 days
n/a
126 days
n/a
+2.8 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
46 years, 1938 to 1983
A day with at least 37.9 mm (1.5 in) of rain is expected about once in 2 years. A day with at least 89.2 mm (3.5 in) of rain is expected about once in 100 years.
Rainfall return levels at Lethbridge A: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
37.9 mm (1.5 in)
5 years
52.8 mm (2.1 in)
10 years
62.2 mm (2.4 in)
25 years
73.5 mm (2.9 in)
50 years
81.5 mm (3.2 in)
Longer than the 46 years of record
100 years
89.2 mm (3.5 in)
Longer than the 46 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, 46 years of values from 1938 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: 85.4 mm (3.4 in) in 1980; 71.9 mm (2.8 in) in 1963; 68.6 mm (2.7 in) in 1978.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Download the Data
Data for Lethbridge A standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Lethbridge A 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.