Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at St Catharines Cda. 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 St Catharines Cda, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
20.6 C (69.1 F)
-22.8 C (-9.0 F)
n/a
n/a
Feb
18.9 C (66.0 F)
-24.4 C (-11.9 F)
n/a
n/a
Mar
26.1 C (79.0 F)
-18.9 C (-2.0 F)
n/a
n/a
Apr
29.4 C (84.9 F)
-9.4 C (15.1 F)
n/a
n/a
May
33.3 C (91.9 F)
-2.2 C (28.0 F)
n/a
n/a
Jun
36.7 C (98.1 F)
0.0 C (32.0 F)
n/a
n/a
Jul
40.0 C (104.0 F)
5.0 C (41.0 F)
n/a
n/a
Aug
36.7 C (98.1 F)
5.0 C (41.0 F)
n/a
n/a
Sep
36.1 C (97.0 F)
0.6 C (33.1 F)
n/a
n/a
Oct
30.6 C (87.1 F)
-5.6 C (21.9 F)
n/a
n/a
Nov
27.2 C (81.0 F)
-13.3 C (8.1 F)
n/a
n/a
Dec
17.2 C (63.0 F)
-20.6 C (-5.1 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at St Catharines Cda still stand. 1934 holds the most, with 70.
Standing records at St Catharines Cda by the year they were set
Year set
Standing records
1928
6
1929
57
1930
57
1931
46
1932
48
1933
66
1934
70
1935
47
1936
64
1937
31
1938
45
1939
31
1940
45
1941
41
1942
34
1943
41
1944
29
1945
68
1946
42
1947
35
1948
43
1949
43
1950
52
1951
32
1952
26
1953
27
1954
46
1955
27
1956
37
1957
40
1958
32
1959
26
1960
29
1961
22
1962
41
1963
18
1964
20
All-Time Record Progression
1 new records
1 all-time records were set at St Catharines Cda between 23 July 1962 and 23 July 1962. Each dot is a new record.
When St Catharines Cda set new all-time records
Date
Kind
Detail
1962-07-23
Record daily precipitation
Record daily precipitation 74.9 mm (2.9 in)
Wettest Day of Each Month
Jul: 74.9 mm (2.9 in)
The wettest day on record for each calendar month at St Catharines Cda. The most was 74.9 mm (2.9 in) on 23 July 1962.
Record daily precipitation for each month at St Catharines Cda
Month
Record daily precipitation (mm)
Date
Jan
42.9 mm (1.7 in)
1 January 1932
Feb
62.2 mm (2.4 in)
16 February 1954
Mar
46.5 mm (1.8 in)
31 March 1945
Apr
34.5 mm (1.4 in)
21 April 1937
May
50.8 mm (2.0 in)
15 May 1942
Jun
47.8 mm (1.9 in)
28 June 1957
Jul
74.9 mm (2.9 in)
23 July 1962
Aug
74.9 mm (2.9 in)
6 August 1962
Sep
61.5 mm (2.4 in)
18 September 1945
Oct
51.6 mm (2.0 in)
16 October 1943
Nov
39.1 mm (1.5 in)
7 November 1941
Dec
38.1 mm (1.5 in)
21 December 1949
Period of Record Coverage
1928 to 1964
Complete yearUnder 90 percent of days
37 years of record at St Catharines Cda, 1928 to 1964. 4 years have data for under 90 percent of days and are left out of rankings: 1928, 1955, 1963, 1964.
Cooler than the station meanWarmer than the station mean
One stripe for each of 32 complete years at St Catharines Cda, 1929 to 1962. Blue stripes are years cooler than the station's own mean of 8.9 C (48.1 F); red stripes are warmer. The coolest year was 1940, at 7.8 C (46.1 F), and the warmest was 1953, at 10.4 C (50.8 F). The strongest colour marks a difference of 1.6 C (2.9 F).
Annual mean temperature at St Catharines Cda as warming stripes, 1929 to 1962
Year
Annual mean temperature
Difference from the station mean
1929
8.1 C
-0.83 C
1930
9.0 C
+0.07 C
1931
10.1 C
+1.17 C
1932
9.4 C
+0.42 C
1933
9.1 C
+0.20 C
1934
8.2 C
-0.69 C
1935
8.5 C
-0.48 C
1936
8.4 C
-0.49 C
1937
9.1 C
+0.17 C
1938
9.5 C
+0.54 C
1939
9.0 C
+0.03 C
1940
7.8 C
-1.11 C
1941
9.4 C
+0.50 C
1942
8.9 C
-0.06 C
1943
8.3 C
-0.59 C
1945
8.9 C
-0.02 C
1946
10.0 C
+1.05 C
1947
9.2 C
+0.30 C
1948
8.6 C
-0.29 C
1949
9.8 C
+0.90 C
1950
8.4 C
-0.58 C
1951
8.9 C
+0.01 C
1952
9.7 C
+0.76 C
1953
10.4 C
+1.50 C
1954
8.9 C
-0.01 C
1956
8.4 C
-0.55 C
1957
9.1 C
+0.20 C
1958
8.2 C
-0.76 C
1959
8.9 C
-0.04 C
1960
8.4 C
-0.55 C
1961
8.8 C
-0.13 C
1962
8.2 C
-0.75 C
The fitted trend in annual mean temperature here over 1929 to 1962 is -0.04 C (-0.28 to 0.19) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.1 F (-0.5 to 0.3) per decade. The slope is a straight line fitted to 32 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at St Catharines Cda
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.04 C (-0.28 to 0.19) per decade
-0.1 F (-0.5 to 0.3) per decade
1929 to 1962
32
Not clearly different from zero
Mean daily maximum
-0.01 C (-0.29 to 0.26) per decade
-0.03 F (-0.52 to 0.46) per decade
1929 to 1962
32
Not clearly different from zero
Mean daily minimum
-0.1 C (-0.3 to 0.2) per decade
-0.1 F (-0.5 to 0.3) per decade
1929 to 1962
32
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
1928 to 1964
Yearly extremes at St Catharines Cda: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
40.0 C (104.0 F)
1936
34.4 C (93.9 F)
37
Coldest night (TNn)
-24.4 C (-11.9 F)
1934
-18.3 C (-0.9 F)
37
Wettest day (Rx1day)
74.9 mm (2.9 in)
1962
45.7 mm (1.8 in)
37
Wettest five days (Rx5day)
117.9 mm (4.6 in)
1945
63.2 mm (2.5 in)
37
Longest dry spell (CDD)
28 days
1943
16 days
37
Hottest day (TXx)
The hottest day of the year at St Catharines Cda, 1928 to 1964. The record is 40.0 C (104.0 F) in 1936, marked on the chart; the median year is 34.4 C (93.9 F).
Hottest day (TXx) at St Catharines Cda by year
Year
Hottest day (TXx)
1928
20.0 C (68.0 F)
1929
33.9 C (93.0 F)
1930
36.7 C (98.1 F)
1931
36.7 C (98.1 F)
1932
34.4 C (93.9 F)
1933
36.7 C (98.1 F)
1934
36.1 C (97.0 F)
1935
34.4 C (93.9 F)
1936
40.0 C (104.0 F)
1937
33.3 C (91.9 F)
1938
34.4 C (93.9 F)
1939
35.6 C (96.1 F)
1940
32.2 C (90.0 F)
1941
36.7 C (98.1 F)
1942
33.3 C (91.9 F)
1943
33.3 C (91.9 F)
1944
36.7 C (98.1 F)
1945
33.3 C (91.9 F)
1946
33.9 C (93.0 F)
1947
34.4 C (93.9 F)
1948
36.7 C (98.1 F)
1949
35.6 C (96.1 F)
1950
32.2 C (90.0 F)
1951
32.8 C (91.0 F)
1952
34.4 C (93.9 F)
1953
36.1 C (97.0 F)
1954
33.9 C (93.0 F)
1955
36.1 C (97.0 F)
1956
33.9 C (93.0 F)
1957
34.4 C (93.9 F)
1958
31.7 C (89.1 F)
1959
34.4 C (93.9 F)
1960
32.2 C (90.0 F)
1961
32.8 C (91.0 F)
1962
33.3 C (91.9 F)
1963
21.1 C (70.0 F)
1964
33.9 C (93.0 F)
Coldest night (TNn)
The coldest night of the year at St Catharines Cda, 1928 to 1964. The record is -24.4 C (-11.9 F) in 1934, marked on the chart; the median year is -18.3 C (-0.9 F).
Coldest night (TNn) at St Catharines Cda by year
Year
Coldest night (TNn)
1928
-12.8 C (9.0 F)
1929
-19.4 C (-2.9 F)
1930
-17.2 C (1.0 F)
1931
-16.7 C (1.9 F)
1932
-13.9 C (7.0 F)
1933
-20.0 C (-4.0 F)
1934
-24.4 C (-11.9 F)
1935
-20.6 C (-5.1 F)
1936
-19.4 C (-2.9 F)
1937
-14.4 C (6.1 F)
1938
-22.2 C (-8.0 F)
1939
-18.9 C (-2.0 F)
1940
-17.2 C (1.0 F)
1941
-15.0 C (5.0 F)
1942
-21.1 C (-6.0 F)
1943
-23.3 C (-9.9 F)
1944
-17.2 C (1.0 F)
1945
-22.8 C (-9.0 F)
1946
-16.7 C (1.9 F)
1947
-15.6 C (3.9 F)
1948
-19.4 C (-2.9 F)
1949
-15.6 C (3.9 F)
1950
-18.9 C (-2.0 F)
1951
-17.8 C (0.0 F)
1952
-15.0 C (5.0 F)
1953
-12.8 C (9.0 F)
1954
-18.3 C (-0.9 F)
1955
-15.0 C (5.0 F)
1956
-16.1 C (3.0 F)
1957
-18.3 C (-0.9 F)
1958
-20.0 C (-4.0 F)
1959
-18.3 C (-0.9 F)
1960
-17.8 C (0.0 F)
1961
-19.4 C (-2.9 F)
1962
-19.4 C (-2.9 F)
1963
-22.2 C (-8.0 F)
1964
-5.0 C (23.0 F)
Wettest day (Rx1day)
The wettest day of the year at St Catharines Cda, 1928 to 1964. The record is 74.9 mm (2.9 in) in 1962, marked on the chart; the median year is 45.7 mm (1.8 in).
Wettest day (Rx1day) at St Catharines Cda by year
Year
Wettest day (Rx1day)
1928
14.5 mm (0.6 in)
1929
45.7 mm (1.8 in)
1930
37.8 mm (1.5 in)
1931
36.1 mm (1.4 in)
1932
51.6 mm (2.0 in)
1933
42.4 mm (1.7 in)
1934
35.6 mm (1.4 in)
1935
49.3 mm (1.9 in)
1936
30.0 mm (1.2 in)
1937
34.5 mm (1.4 in)
1938
73.2 mm (2.9 in)
1939
46.0 mm (1.8 in)
1940
34.3 mm (1.4 in)
1941
47.0 mm (1.9 in)
1942
55.9 mm (2.2 in)
1943
51.6 mm (2.0 in)
1944
34.3 mm (1.4 in)
1945
61.5 mm (2.4 in)
1946
47.5 mm (1.9 in)
1947
43.9 mm (1.7 in)
1948
61.0 mm (2.4 in)
1949
41.9 mm (1.6 in)
1950
32.0 mm (1.3 in)
1951
34.3 mm (1.4 in)
1952
51.8 mm (2.0 in)
1953
50.8 mm (2.0 in)
1954
62.2 mm (2.4 in)
1955
44.2 mm (1.7 in)
1956
49.5 mm (1.9 in)
1957
47.8 mm (1.9 in)
1958
30.5 mm (1.2 in)
1959
31.8 mm (1.3 in)
1960
28.4 mm (1.1 in)
1961
49.0 mm (1.9 in)
1962
74.9 mm (2.9 in)
1963
14.5 mm (0.6 in)
1964
60.2 mm (2.4 in)
Wettest five days (Rx5day)
The wettest five days of the year at St Catharines Cda, 1928 to 1964. The record is 117.9 mm (4.6 in) in 1945, marked on the chart; the median year is 63.2 mm (2.5 in).
Wettest five days (Rx5day) at St Catharines Cda by year
Year
Wettest five days (Rx5day)
1928
31.8 mm (1.3 in)
1929
74.9 mm (2.9 in)
1930
54.5 mm (2.1 in)
1931
46.2 mm (1.8 in)
1932
84.6 mm (3.3 in)
1933
50.5 mm (2.0 in)
1934
57.9 mm (2.3 in)
1935
60.0 mm (2.4 in)
1936
54.7 mm (2.2 in)
1937
63.2 mm (2.5 in)
1938
83.6 mm (3.3 in)
1939
64.0 mm (2.5 in)
1940
59.2 mm (2.3 in)
1941
80.0 mm (3.1 in)
1942
76.2 mm (3.0 in)
1943
66.1 mm (2.6 in)
1944
79.3 mm (3.1 in)
1945
117.9 mm (4.6 in)
1946
85.1 mm (3.4 in)
1947
70.7 mm (2.8 in)
1948
61.0 mm (2.4 in)
1949
62.4 mm (2.5 in)
1950
70.6 mm (2.8 in)
1951
52.1 mm (2.1 in)
1952
56.4 mm (2.2 in)
1953
56.2 mm (2.2 in)
1954
84.8 mm (3.3 in)
1955
83.7 mm (3.3 in)
1956
68.1 mm (2.7 in)
1957
61.8 mm (2.4 in)
1958
47.2 mm (1.9 in)
1959
53.4 mm (2.1 in)
1960
54.8 mm (2.2 in)
1961
75.4 mm (3.0 in)
1962
88.7 mm (3.5 in)
1963
37.9 mm (1.5 in)
1964
80.0 mm (3.1 in)
Longest dry spell (CDD)
The longest dry spell of the year at St Catharines Cda, 1928 to 1964. The record is 28 days in 1943, marked on the chart; the median year is 16 days.
Longest dry spell (CDD) at St Catharines Cda by year
Year
Longest dry spell (CDD)
1928
11 days
1929
19 days
1930
24 days
1931
16 days
1932
14 days
1933
15 days
1934
17 days
1935
17 days
1936
23 days
1937
16 days
1938
15 days
1939
20 days
1940
19 days
1941
22 days
1942
16 days
1943
28 days
1944
14 days
1945
17 days
1946
13 days
1947
18 days
1948
20 days
1949
18 days
1950
15 days
1951
15 days
1952
16 days
1953
13 days
1954
14 days
1955
16 days
1956
15 days
1957
23 days
1958
14 days
1959
15 days
1960
13 days
1961
19 days
1962
18 days
1963
7 days
1964
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
32 years with a frost
Across 32 years with a frost, the median last spring frost at St Catharines Cda falls on 3 May and the median first autumn frost on 17 October, which leaves a median of 165 days between them.
Fitted over all years, the growing season changes by -0.1 days per decade at this station.
Frost dates and growing season at St Catharines Cda
Measure
Median, all years
Earliest period
Recent period (1931 to 1962)
Recent against earliest
Fitted trend
Last spring frost
3 May
n/a
4 May
n/a
+2.1 days per decade
First autumn frost
17 October
n/a
17 October
n/a
+2.0 days per decade
Growing days
165 days
n/a
164 days
n/a
-0.1 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
33 years, 1929 to 1962
A day with at least 44.0 mm (1.7 in) of rain is expected about once in 2 years. A day with at least 81.5 mm (3.2 in) of rain is expected about once in 100 years.
Rainfall return levels at St Catharines Cda: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
44.0 mm (1.7 in)
5 years
55.0 mm (2.2 in)
10 years
61.9 mm (2.4 in)
25 years
70.1 mm (2.8 in)
50 years
75.9 mm (3.0 in)
Longer than the 33 years of record
100 years
81.5 mm (3.2 in)
Longer than the 33 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, 33 years of values from 1929 to 1962.
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: 74.9 mm (2.9 in) in 1962; 73.2 mm (2.9 in) in 1938; 62.2 mm (2.4 in) in 1954.
Download the Data
Data for St Catharines Cda standing records by year: CSV or JSON. Field meanings are on the data page.
Data for St Catharines Cda 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.