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St Catharines Weather Records (CA006137285)

Record envelope, standing records and threshold days for St Catharines (CA006137285), Ontario, Canada, with 114 years of record.

Key Facts for St Catharines

  • St Catharines (CA006137285) is a weather station in Ontario, Canada at 43.20 latitude and -79.25 longitude, 91 m (299 ft) above sea level.
  • The station reports from 1882 to 1995, 114 years of record.
  • 1,464 records set at St Catharines still stand.
  • Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
  • St Catharines set a daily record low maximum temperature of -10.0 C (14.0 F) on 30 December 1983.

About the Station

  • Location: Ontario, Canada, 43.20 latitude, -79.25 longitude.
  • Elevation: 91 m (299 ft).
  • Period of record: 1882 to 1995, 114 years.
  • Eligible elements: tmax, tmin, prcp, snow.

Daily Record Envelope and 2026

0 days at or beyond a record
Daily record high and record low at St Catharines, with 2026 drawn through them The band shows the record high and record low for each calendar day at St Catharines. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius. -40-2002040 JanFebMarAprMayJunJulAugSepOctNovDec
The band shows the record high and record low for each calendar day at St Catharines. 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, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan20.0 C (68.0 F)-23.3 C (-9.9 F)n/an/a
Feb19.4 C (66.9 F)-23.9 C (-11.0 F)n/an/a
Mar26.7 C (80.1 F)-19.4 C (-2.9 F)n/an/a
Apr32.2 C (90.0 F)-15.0 C (5.0 F)n/an/a
May32.2 C (90.0 F)-4.4 C (24.1 F)n/an/a
Jun36.1 C (97.0 F)1.0 C (33.8 F)n/an/a
Jul40.0 C (104.0 F)4.0 C (39.2 F)n/an/a
Aug38.3 C (100.9 F)4.0 C (39.2 F)n/an/a
Sep36.7 C (98.1 F)0.0 C (32.0 F)n/an/a
Oct31.1 C (88.0 F)-7.0 C (19.4 F)n/an/a
Nov25.0 C (77.0 F)-13.9 C (7.0 F)n/an/a
Dec21.0 C (69.8 F)-24.4 C (-11.9 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at St Catharines by the year they were set 1,464 records at St Catharines still stand. 1936 holds the most, with 44. 02040601901: 31902: 271903: 291911: 21912: 171913: 71914: 151915: 171918: 131919: 281920: 381921: 291922: 111923: 351924: 231925: 311926: 301927: 311928: 251929: 281930: 301931: 201932: 181933: 391934: 341935: 251936: 441937: 241938: 261939: 171940: 261941: 231942: 241943: 251944: 131945: 351946: 301947: 281948: 211949: 331950: 231951: 221952: 111953: 201954: 221955: 301956: 111964: 111965: 241966: 191967: 251968: 81969: 141970: 141971: 121972: 221973: 281974: 241975: 181976: 71977: 171978: 101979: 251980: 91981: 261982: 251983: 131901191519241931193819451952196619731980
1,464 records at St Catharines still stand. 1936 holds the most, with 44.
Standing records at St Catharines by the year they were set
Year setStanding records
19013
190227
190329
19112
191217
19137
191415
191517
191813
191928
192038
192129
192211
192335
192423
192531
192630
192731
192825
192928
193030
193120
193218
193339
193434
193525
193644
193724
193826
193917
194026
194123
194224
194325
194413
194535
194630
194728
194821
194933
195023
195122
195211
195320
195422
195530
195611
196411
196524
196619
196725
19688
196914
197014
197112
197222
197328
197424
197518
19767
197717
197810
197925
19809
198126
198225
198313

All-Time Record Progression

1 new records
When St Catharines set new all-time records 1 all-time records were set at St Catharines between 1 August 1955 and 1 August 1955. Each dot is a new record. Record high minimum temperature1 August 1955: Record high minimum temperature 25.6 C (78.1 F)1955
1 all-time records were set at St Catharines between 1 August 1955 and 1 August 1955. Each dot is a new record.
When St Catharines set new all-time records
DateKindDetail
1955-08-01Record high minimum temperatureRecord high minimum temperature 25.6 C (78.1 F)

Wettest Day of Each Month

Sep: 77.0 mm (3.0 in)
Record daily precipitation for each month at St Catharines The wettest day on record for each calendar month at St Catharines. The most was 77.0 mm (3.0 in) on 29 September 1924. 020406080 Jan: 45.7 mm (1.8 in), 22 January 1902 Jan Feb: 58.2 mm (2.3 in), 16 February 1954 Feb Mar: 48.8 mm (1.9 in), 31 March 1945 Mar Apr: 36.8 mm (1.4 in), 10 April 1939 Apr May: 50.8 mm (2.0 in), 16 May 1976 May Jun: 70.9 mm (2.8 in), 25 June 1968 Jun Jul: 60.5 mm (2.4 in), 24 July 1920 Jul Aug: 69.3 mm (2.7 in), 10 August 1938 Aug Sep: 77.0 mm (3.0 in), 29 September 1924 Sep Oct: 59.7 mm (2.4 in), 15 October 1954 Oct Nov: 37.1 mm (1.5 in), 28 November 1968 Nov Dec: 41.9 mm (1.6 in), 11 December 1944 Dec
The wettest day on record for each calendar month at St Catharines. The most was 77.0 mm (3.0 in) on 29 September 1924.
Record daily precipitation for each month at St Catharines
MonthRecord daily precipitation (mm)Date
Jan45.7 mm (1.8 in)22 January 1902
Feb58.2 mm (2.3 in)16 February 1954
Mar48.8 mm (1.9 in)31 March 1945
Apr36.8 mm (1.4 in)10 April 1939
May50.8 mm (2.0 in)16 May 1976
Jun70.9 mm (2.8 in)25 June 1968
Jul60.5 mm (2.4 in)24 July 1920
Aug69.3 mm (2.7 in)10 August 1938
Sep77.0 mm (3.0 in)29 September 1924
Oct59.7 mm (2.4 in)15 October 1954
Nov37.1 mm (1.5 in)28 November 1968
Dec41.9 mm (1.6 in)11 December 1944

Period of Record Coverage

1901 to 1983
Days with data per year at St Catharines 67 years of record at St Catharines, 1901 to 1983. 15 years have data for under 90 percent of days and are left out of rankings: 1901, 1903, 1911, 1912, 1913, 1914, 1918, 1964 and others. 1901: 61 of 365 days1902: 360 of 365 days1903: 289 of 365 days1911: 95 of 365 days1912: 168 of 366 days1913: 78 of 365 days1914: 45 of 365 days1915: 364 of 365 days1918: 184 of 365 days1919: 365 of 365 days1920: 366 of 366 days1921: 365 of 365 days1922: 365 of 365 days1923: 365 of 365 days1924: 365 of 366 days1925: 365 of 365 days1926: 365 of 365 days1927: 364 of 365 days1928: 366 of 366 days1929: 365 of 365 days1930: 365 of 365 days1931: 364 of 365 days1932: 366 of 366 days1933: 364 of 365 days1934: 365 of 365 days1935: 364 of 365 days1936: 366 of 366 days1937: 365 of 365 days1938: 365 of 365 days1939: 365 of 365 days1940: 366 of 366 days1941: 365 of 365 days1942: 365 of 365 days1943: 365 of 365 days1944: 366 of 366 days1945: 365 of 365 days1946: 365 of 365 days1947: 365 of 365 days1948: 366 of 366 days1949: 365 of 365 days1950: 365 of 365 days1951: 365 of 365 days1952: 366 of 366 days1953: 365 of 365 days1954: 365 of 365 days1955: 365 of 365 days1956: 335 of 366 days1964: 108 of 366 days1965: 362 of 365 days1966: 339 of 365 days1967: 341 of 365 days1968: 350 of 366 days1969: 297 of 365 days1970: 360 of 365 days1971: 330 of 365 days1972: 366 of 366 days1973: 334 of 365 days1974: 365 of 365 days1975: 229 of 365 days1976: 168 of 366 days1977: 239 of 365 days1978: 202 of 365 days1979: 305 of 365 days1980: 333 of 366 days1981: 350 of 365 days1982: 236 of 365 days1983: 358 of 365 days192019301940195019701980
67 years of record at St Catharines, 1901 to 1983. 15 years have data for under 90 percent of days and are left out of rankings: 1901, 1903, 1911, 1912, 1913, 1914, 1918, 1964 and others.
Days with data per year at St Catharines
YearDays with dataShare of yearComplete
19016117%No
190236099%Yes
190328979%No
19119526%No
191216846%No
19137821%No
19144512%No
1915364100%Yes
191818450%No
1919365100%Yes
1920366100%Yes
1921365100%Yes
1922365100%Yes
1923365100%Yes
1924365100%Yes
1925365100%Yes
1926365100%Yes
1927364100%Yes
1928366100%Yes
1929365100%Yes
1930365100%Yes
1931364100%Yes
1932366100%Yes
1933364100%Yes
1934365100%Yes
1935364100%Yes
1936366100%Yes
1937365100%Yes
1938365100%Yes
1939365100%Yes
1940366100%Yes
1941365100%Yes
1942365100%Yes
1943365100%Yes
1944366100%Yes
1945365100%Yes
1946365100%Yes
1947365100%Yes
1948366100%Yes
1949365100%Yes
1950365100%Yes
1951365100%Yes
1952366100%Yes
1953365100%Yes
1954365100%Yes
1955365100%Yes
195633592%Yes
196410830%No
196536299%Yes
196633993%Yes
196734193%Yes
196835096%Yes
196929781%No
197036099%Yes
197133090%Yes
1972366100%Yes
197333492%Yes
1974365100%Yes
197522963%No
197616846%No
197723965%No
197820255%No
197930584%No
198033391%Yes
198135096%Yes
198223665%No
198335898%Yes

Latest Records

20
Latest records at St Catharines
DateStationRecordValueBeat old record byOld record stoodSignificance
30 December 1983St Catharines, CAdaily low max-10.0 C (14.0 F)2.2 C (4.0 F)48 years26 of 100 (Routine)
25 December 1983St Catharines, CAdaily low max-11.0 C (12.2 F)1.0 C (1.8 F)58 years26 of 100 (Routine)
24 December 1983St Catharines, CAdaily low max-11.5 C (11.3 F)4.3 C (7.7 F)13 years20 of 100 (Routine)
23 December 1983St Catharines, CAdaily low min-14.0 C (6.8 F)0.1 C (0.2 F)40 years20 of 100 (Routine)
15 December 1983St Catharines, CAdaily high min2.0 C (35.6 F)0.3 C (0.5 F)64 years27 of 100 (Routine)
13 November 1983St Catharines, CAdaily low max (Tie)0.0 C (32.0 F)tie62 years6 of 100 (Routine)
20 September 1983St Catharines, CAdaily high min20.0 C (68.0 F)1.7 C (3.1 F)64 years30 of 100 (Routine)
10 September 1983St Catharines, CAdaily high min23.0 C (73.4 F)1.3 C (2.3 F)57 years27 of 100 (Routine)
6 September 1983St Catharines, CAdaily rain17.5 mm (0.7 in)3.3 mm (0.13 in)32 years20 of 100 (Routine)
6 September 1983St Catharines, CAdaily high min23.0 C (73.4 F)0.8 C (1.4 F)40 years21 of 100 (Routine)
20 August 1983St Catharines, CAdaily high min23.0 C (73.4 F)1.3 C (2.3 F)12 years14 of 100 (Routine)
18 August 1983St Catharines, CAdaily high min22.0 C (71.6 F)0.3 C (0.5 F)42 years20 of 100 (Routine)
11 August 1983St Catharines, CAdaily low max (Tie)20.0 C (68.0 F)tie28 years4 of 100 (Routine)
8 August 1983St Catharines, CAdaily high min23.0 C (73.4 F)0.8 C (1.4 F)64 years29 of 100 (Routine)
16 July 1983St Catharines, CAdaily high max34.0 C (93.2 F)0.7 C (1.3 F)68 years29 of 100 (Routine)
15 July 1983St Catharines, CAdaily high max34.0 C (93.2 F)0.7 C (1.3 F)28 years17 of 100 (Routine)
29 May 1983St Catharines, CAdaily rain16.1 mm (0.6 in)5.2 mm (0.20 in)29 years20 of 100 (Routine)
21 March 1983St Catharines, CAdaily snowfall15.0 cm (5.9 in)4.8 cm (1.9 in)46 years34 of 100 (Routine)
21 March 1983St Catharines, CAdaily rain15.0 mm (0.6 in)2.8 mm (0.11 in)16 years19 of 100 (Routine)
18 March 1983St Catharines, CAdaily rain22.0 mm (0.9 in)7.5 mm (0.30 in)64 years20 of 100 (Routine)

Climate Trend

42 complete years, 1902 to 1983
Annual mean temperature at St Catharines as warming stripes, 1902 to 1983 One stripe for each of 42 complete years at St Catharines, 1902 to 1983. Blue stripes are years cooler than the station's own mean of 9.1 C (48.3 F); red stripes are warmer. The coolest year was 1926, at 7.3 C (45.2 F), and the warmest was 1953, at 10.6 C (51.1 F). The strongest colour marks a difference of 1.8 C (3.2 F). 1902: 8.0 C, -1.1 C from the station mean1915: 9.7 C, +0.7 C from the station mean1919: 9.6 C, +0.5 C from the station mean1920: 8.4 C, -0.7 C from the station mean1921: 10.6 C, +1.5 C from the station mean1922: 9.4 C, +0.4 C from the station mean1923: 8.3 C, -0.7 C from the station mean1924: 7.7 C, -1.4 C from the station mean1925: 8.3 C, -0.8 C from the station mean1926: 7.3 C, -1.7 C from the station mean1927: 8.9 C, -0.2 C from the station mean1928: 8.7 C, -0.4 C from the station mean1929: 8.3 C, -0.7 C from the station mean1930: 9.2 C, +0.1 C from the station mean1931: 10.2 C, +1.1 C from the station mean1932: 9.2 C, +0.2 C from the station mean1933: 9.2 C, +0.1 C from the station mean1934: 8.1 C, -0.9 C from the station mean1935: 8.3 C, -0.8 C from the station mean1936: 8.4 C, -0.7 C from the station mean1937: 9.1 C, 0.0 C from the station mean1938: 9.6 C, +0.5 C from the station mean1939: 8.9 C, -0.2 C from the station mean1940: 7.7 C, -1.3 C from the station mean1941: 9.6 C, +0.5 C from the station mean1942: 8.9 C, -0.1 C from the station mean1943: 8.4 C, -0.6 C from the station mean1944: 9.3 C, +0.2 C from the station mean1945: 8.8 C, -0.2 C from the station mean1946: 10.0 C, +0.9 C from the station mean1947: 9.4 C, +0.3 C from the station mean1948: 9.4 C, +0.3 C from the station mean1949: 10.6 C, +1.5 C from the station mean1950: 8.8 C, -0.3 C from the station mean1951: 9.4 C, +0.3 C from the station mean1952: 10.2 C, +1.1 C from the station mean1953: 10.6 C, +1.5 C from the station mean1954: 9.6 C, +0.6 C from the station mean1955: 10.4 C, +1.3 C from the station mean1970: 8.9 C, -0.2 C from the station mean1972: 8.1 C, -1.0 C from the station mean1983: 9.6 C, +0.5 C from the station mean190219101920193019401950196019701980
One stripe for each of 42 complete years at St Catharines, 1902 to 1983. Blue stripes are years cooler than the station's own mean of 9.1 C (48.3 F); red stripes are warmer. The coolest year was 1926, at 7.3 C (45.2 F), and the warmest was 1953, at 10.6 C (51.1 F). The strongest colour marks a difference of 1.8 C (3.2 F).
Annual mean temperature at St Catharines as warming stripes, 1902 to 1983
YearAnnual mean temperatureDifference from the station mean
19028.0 C-1.09 C
19159.7 C+0.66 C
19199.6 C+0.48 C
19208.4 C-0.69 C
192110.6 C+1.51 C
19229.4 C+0.37 C
19238.3 C-0.73 C
19247.7 C-1.40 C
19258.3 C-0.82 C
19267.3 C-1.75 C
19278.9 C-0.17 C
19288.7 C-0.41 C
19298.3 C-0.75 C
19309.2 C+0.10 C
193110.2 C+1.08 C
19329.2 C+0.17 C
19339.2 C+0.09 C
19348.1 C-0.95 C
19358.3 C-0.77 C
19368.4 C-0.71 C
19379.1 C+0.00 C
19389.6 C+0.50 C
19398.9 C-0.17 C
19407.7 C-1.35 C
19419.6 C+0.51 C
19428.9 C-0.14 C
19438.4 C-0.63 C
19449.3 C+0.19 C
19458.8 C-0.25 C
194610.0 C+0.90 C
19479.4 C+0.31 C
19489.4 C+0.34 C
194910.6 C+1.52 C
19508.8 C-0.27 C
19519.4 C+0.30 C
195210.2 C+1.14 C
195310.6 C+1.53 C
19549.6 C+0.56 C
195510.4 C+1.31 C
19708.9 C-0.22 C
19728.1 C-0.96 C
19839.6 C+0.51 C

The fitted trend in annual mean temperature here over 1902 to 1983 is 0.14 C (-0.02 to 0.30) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.26 F (-0.03 to 0.55) per decade. The slope is a straight line fitted to 42 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at St Catharines
MeasurePer decade (C)Per decade (F)PeriodComplete yearsReading
Annual mean temperature0.14 C (-0.02 to 0.30) per decade0.26 F (-0.03 to 0.55) per decade1902 to 198342Not clearly different from zero
Mean daily maximum0.1 C (-0.1 to 0.3) per decade0.1 F (-0.2 to 0.5) per decade1902 to 198342Not clearly different from zero
Mean daily minimum0.2 C (0.1 to 0.4) per decade0.4 F (0.1 to 0.7) per decade1902 to 198342Rise

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

1882 to 1983
Yearly extremes at St Catharines: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)40.0 C (104.0 F)193634.4 C (93.9 F)67
Coldest night (TNn)-24.4 C (-11.9 F)1925-18.9 C (-2.0 F)67
Wettest day (Rx1day)77.0 mm (3.0 in)192441.2 mm (1.6 in)68
Wettest five days (Rx5day)122.9 mm (4.8 in)194561.4 mm (2.4 in)68
Longest dry spell (CDD)36 days192417 days68

Hottest day (TXx)

Hottest day (TXx) at St Catharines by year The hottest day of the year at St Catharines, 1882 to 1983. 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). 1020304019001920194019601980Record: 40.0 C (104.0 F) in 1936
The hottest day of the year at St Catharines, 1882 to 1983. 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 by year
YearHottest day (TXx)
1882n/a
1883n/a
1884n/a
190120.6 C (69.1 F)
190233.9 C (93.0 F)
190333.3 C (91.9 F)
191125.0 C (77.0 F)
191234.4 C (93.9 F)
191335.6 C (96.1 F)
191415.0 C (59.0 F)
191533.3 C (91.9 F)
191836.7 C (98.1 F)
191935.6 C (96.1 F)
192032.8 C (91.0 F)
192135.6 C (96.1 F)
192234.4 C (93.9 F)
192335.0 C (95.0 F)
192432.2 C (90.0 F)
192535.6 C (96.1 F)
192633.3 C (91.9 F)
192734.4 C (93.9 F)
192833.3 C (91.9 F)
192934.4 C (93.9 F)
193035.0 C (95.0 F)
193135.0 C (95.0 F)
193233.9 C (93.0 F)
193337.2 C (99.0 F)
193434.4 C (93.9 F)
193534.4 C (93.9 F)
193640.0 C (104.0 F)
193734.4 C (93.9 F)
193834.4 C (93.9 F)
193934.4 C (93.9 F)
194033.3 C (91.9 F)
194136.1 C (97.0 F)
194234.4 C (93.9 F)
194335.0 C (95.0 F)
194435.6 C (96.1 F)
194533.9 C (93.0 F)
194635.0 C (95.0 F)
194735.0 C (95.0 F)
194838.3 C (100.9 F)
194937.2 C (99.0 F)
195032.8 C (91.0 F)
195134.4 C (93.9 F)
195236.1 C (97.0 F)
195336.7 C (98.1 F)
195433.3 C (91.9 F)
195536.7 C (98.1 F)
195634.4 C (93.9 F)
196433.9 C (93.0 F)
196532.2 C (90.0 F)
196635.6 C (96.1 F)
196731.7 C (89.1 F)
196833.3 C (91.9 F)
196933.9 C (93.0 F)
197031.7 C (89.1 F)
197132.8 C (91.0 F)
197232.8 C (91.0 F)
197334.4 C (93.9 F)
197433.3 C (91.9 F)
197536.1 C (97.0 F)
197632.2 C (90.0 F)
197735.5 C (95.9 F)
197835.0 C (95.0 F)
197931.5 C (88.7 F)
198033.0 C (91.4 F)
198134.0 C (93.2 F)
198233.0 C (91.4 F)
198334.0 C (93.2 F)

Coldest night (TNn)

Coldest night (TNn) at St Catharines by year The coldest night of the year at St Catharines, 1882 to 1983. The record is -24.4 C (-11.9 F) in 1925, marked on the chart; the median year is -18.9 C (-2.0 F). -25-20-15-10-519001920194019601980Record: -24.4 C (-11.9 F) in 1925
The coldest night of the year at St Catharines, 1882 to 1983. The record is -24.4 C (-11.9 F) in 1925, marked on the chart; the median year is -18.9 C (-2.0 F).
Coldest night (TNn) at St Catharines by year
YearColdest night (TNn)
1882n/a
1883n/a
1884n/a
1901-17.8 C (0.0 F)
1902-18.9 C (-2.0 F)
1903-21.7 C (-7.1 F)
1911-16.7 C (1.9 F)
1912-23.3 C (-9.9 F)
1913-11.1 C (12.0 F)
1914-23.9 C (-11.0 F)
1915-18.9 C (-2.0 F)
1918-7.8 C (18.0 F)
1919-21.1 C (-6.0 F)
1920-22.8 C (-9.0 F)
1921-17.8 C (0.0 F)
1922-16.7 C (1.9 F)
1923-18.9 C (-2.0 F)
1924-20.6 C (-5.1 F)
1925-24.4 C (-11.9 F)
1926-18.9 C (-2.0 F)
1927-21.1 C (-6.0 F)
1928-21.1 C (-6.0 F)
1929-19.4 C (-2.9 F)
1930-18.9 C (-2.0 F)
1931-15.6 C (3.9 F)
1932-13.3 C (8.1 F)
1933-20.6 C (-5.1 F)
1934-23.9 C (-11.0 F)
1935-20.0 C (-4.0 F)
1936-20.0 C (-4.0 F)
1937-14.4 C (6.1 F)
1938-21.1 C (-6.0 F)
1939-19.4 C (-2.9 F)
1940-17.2 C (1.0 F)
1941-15.0 C (5.0 F)
1942-21.1 C (-6.0 F)
1943-23.9 C (-11.0 F)
1944-18.9 C (-2.0 F)
1945-22.8 C (-9.0 F)
1946-18.9 C (-2.0 F)
1947-16.1 C (3.0 F)
1948-19.4 C (-2.9 F)
1949-13.9 C (7.0 F)
1950-18.9 C (-2.0 F)
1951-17.2 C (1.0 F)
1952-16.7 C (1.9 F)
1953-12.2 C (10.0 F)
1954-17.8 C (0.0 F)
1955-18.9 C (-2.0 F)
1956-15.6 C (3.9 F)
1964-12.8 C (9.0 F)
1965-15.6 C (3.9 F)
1966-21.7 C (-7.1 F)
1967-19.4 C (-2.9 F)
1968-21.1 C (-6.0 F)
1969-17.8 C (0.0 F)
1970-19.4 C (-2.9 F)
1971-19.4 C (-2.9 F)
1972-19.4 C (-2.9 F)
1973-16.1 C (3.0 F)
1974-20.0 C (-4.0 F)
1975-22.8 C (-9.0 F)
1976-11.1 C (12.0 F)
1977-8.5 C (16.7 F)
1978-8.0 C (17.6 F)
1979-19.0 C (-2.2 F)
1980-22.0 C (-7.6 F)
1981-23.0 C (-9.4 F)
1982-14.0 C (6.8 F)
1983-16.0 C (3.2 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at St Catharines by year The wettest day of the year at St Catharines, 1882 to 1983. The record is 77.0 mm (3.0 in) in 1924, marked on the chart; the median year is 41.2 mm (1.6 in). 02040608019001920194019601980Record: 77.0 mm (3.0 in) in 1924
The wettest day of the year at St Catharines, 1882 to 1983. The record is 77.0 mm (3.0 in) in 1924, marked on the chart; the median year is 41.2 mm (1.6 in).
Wettest day (Rx1day) at St Catharines by year
YearWettest day (Rx1day)
188230.5 mm (1.2 in)
188348.0 mm (1.9 in)
188429.5 mm (1.2 in)
190126.4 mm (1.0 in)
190245.7 mm (1.8 in)
190343.9 mm (1.7 in)
191137.3 mm (1.5 in)
191214.2 mm (0.6 in)
1913n/a
1914n/a
191539.4 mm (1.6 in)
191850.0 mm (2.0 in)
191932.5 mm (1.3 in)
192060.5 mm (2.4 in)
192133.8 mm (1.3 in)
192270.4 mm (2.8 in)
192325.1 mm (1.0 in)
192477.0 mm (3.0 in)
192550.3 mm (2.0 in)
192643.4 mm (1.7 in)
192743.9 mm (1.7 in)
192837.6 mm (1.5 in)
192936.6 mm (1.4 in)
193033.3 mm (1.3 in)
193134.5 mm (1.4 in)
193250.3 mm (2.0 in)
193342.2 mm (1.7 in)
193450.8 mm (2.0 in)
193543.7 mm (1.7 in)
193625.4 mm (1.0 in)
193751.8 mm (2.0 in)
193869.3 mm (2.7 in)
193938.1 mm (1.5 in)
194030.7 mm (1.2 in)
194139.9 mm (1.6 in)
194245.7 mm (1.8 in)
194343.9 mm (1.7 in)
194441.9 mm (1.6 in)
194561.7 mm (2.4 in)
194635.6 mm (1.4 in)
194742.4 mm (1.7 in)
194837.3 mm (1.5 in)
194938.6 mm (1.5 in)
195039.1 mm (1.5 in)
195132.8 mm (1.3 in)
195261.0 mm (2.4 in)
195351.6 mm (2.0 in)
195459.7 mm (2.4 in)
195546.0 mm (1.8 in)
195638.1 mm (1.5 in)
196455.6 mm (2.2 in)
196528.4 mm (1.1 in)
196664.8 mm (2.6 in)
196738.1 mm (1.5 in)
196870.9 mm (2.8 in)
196945.0 mm (1.8 in)
197067.3 mm (2.6 in)
197150.8 mm (2.0 in)
197232.0 mm (1.3 in)
197331.0 mm (1.2 in)
197426.7 mm (1.1 in)
197550.8 mm (2.0 in)
197650.8 mm (2.0 in)
197740.4 mm (1.6 in)
197840.0 mm (1.6 in)
197929.5 mm (1.2 in)
198041.9 mm (1.6 in)
198128.0 mm (1.1 in)
198239.0 mm (1.5 in)
198330.8 mm (1.2 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at St Catharines by year The wettest five days of the year at St Catharines, 1882 to 1983. The record is 122.9 mm (4.8 in) in 1945, marked on the chart; the median year is 61.4 mm (2.4 in). 05010015019001920194019601980Record: 122.9 mm (4.8 in) in 1945
The wettest five days of the year at St Catharines, 1882 to 1983. The record is 122.9 mm (4.8 in) in 1945, marked on the chart; the median year is 61.4 mm (2.4 in).
Wettest five days (Rx5day) at St Catharines by year
YearWettest five days (Rx5day)
188253.1 mm (2.1 in)
188369.1 mm (2.7 in)
188445.7 mm (1.8 in)
190139.4 mm (1.6 in)
190261.7 mm (2.4 in)
190380.5 mm (3.2 in)
191142.4 mm (1.7 in)
191220.8 mm (0.8 in)
1913n/a
1914n/a
191574.5 mm (2.9 in)
191857.9 mm (2.3 in)
191941.4 mm (1.6 in)
192067.6 mm (2.7 in)
192169.6 mm (2.7 in)
192276.8 mm (3.0 in)
192340.6 mm (1.6 in)
1924100.1 mm (3.9 in)
192560.5 mm (2.4 in)
192675.2 mm (3.0 in)
192779.2 mm (3.1 in)
192860.7 mm (2.4 in)
192955.9 mm (2.2 in)
193052.6 mm (2.1 in)
193156.6 mm (2.2 in)
193278.0 mm (3.1 in)
193346.2 mm (1.8 in)
193467.9 mm (2.7 in)
193549.5 mm (1.9 in)
193645.7 mm (1.8 in)
193759.6 mm (2.3 in)
193879.0 mm (3.1 in)
193949.3 mm (1.9 in)
194061.0 mm (2.4 in)
194171.9 mm (2.8 in)
194261.5 mm (2.4 in)
194365.8 mm (2.6 in)
194457.2 mm (2.3 in)
1945122.9 mm (4.8 in)
194667.3 mm (2.6 in)
194775.9 mm (3.0 in)
194860.5 mm (2.4 in)
194957.9 mm (2.3 in)
195087.9 mm (3.5 in)
195151.6 mm (2.0 in)
195269.2 mm (2.7 in)
195360.8 mm (2.4 in)
195484.3 mm (3.3 in)
195595.6 mm (3.8 in)
195653.4 mm (2.1 in)
196470.6 mm (2.8 in)
196546.0 mm (1.8 in)
196668.1 mm (2.7 in)
196770.9 mm (2.8 in)
196876.0 mm (3.0 in)
196951.8 mm (2.0 in)
197074.9 mm (2.9 in)
197162.0 mm (2.4 in)
197257.5 mm (2.3 in)
197371.6 mm (2.8 in)
197455.7 mm (2.2 in)
197561.2 mm (2.4 in)
197667.9 mm (2.7 in)
197787.2 mm (3.4 in)
197857.0 mm (2.2 in)
197968.2 mm (2.7 in)
198052.5 mm (2.1 in)
198151.2 mm (2.0 in)
198281.8 mm (3.2 in)
198348.9 mm (1.9 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at St Catharines by year The longest dry spell of the year at St Catharines, 1882 to 1983. The record is 36 days in 1924, marked on the chart; the median year is 17 days. 1020304019001920194019601980Record: 36 days in 1924
The longest dry spell of the year at St Catharines, 1882 to 1983. The record is 36 days in 1924, marked on the chart; the median year is 17 days.
Longest dry spell (CDD) at St Catharines by year
YearLongest dry spell (CDD)
188224 days
188313 days
188422 days
190111 days
190216 days
190317 days
191116 days
191230 days
1913n/a
1914n/a
191520 days
191818 days
191932 days
192023 days
192111 days
192217 days
192321 days
192436 days
192514 days
192612 days
192715 days
192813 days
192913 days
193024 days
193116 days
193215 days
193333 days
193417 days
193517 days
193621 days
193716 days
193815 days
193920 days
194019 days
194125 days
194226 days
194330 days
194413 days
194513 days
194614 days
194718 days
194814 days
194918 days
195015 days
195112 days
195217 days
195313 days
195413 days
195516 days
195615 days
196411 days
196514 days
196617 days
196716 days
196819 days
196923 days
197014 days
197112 days
197212 days
197315 days
197417 days
197519 days
197617 days
197722 days
197825 days
197924 days
198016 days
198113 days
198221 days
198319 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

42 years with a frost

Across 42 years with a frost, the median last spring frost at St Catharines falls on 2 May and the median first autumn frost on 21 October, which leaves a median of 174 days between them.

Fitted over all years, the growing season changes by +2.9 days per decade at this station.

Frost dates and growing season at St Catharines
MeasureMedian, all yearsEarliest periodRecent period (1929 to 1983)Recent against earliestFitted trend
Last spring frost2 Mayn/a1 Mayn/a-2.5 days per decade
First autumn frost21 Octobern/a20 Octobern/a+0.4 days per decade
Growing days174 daysn/a175 daysn/a+2.9 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

53 years, 1883 to 1983

A day with at least 41.6 mm (1.6 in) of rain is expected about once in 2 years. A day with at least 87.9 mm (3.5 in) of rain is expected about once in 100 years.

Rainfall return levels at St Catharines: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years41.6 mm (1.6 in)
5 years53.6 mm (2.1 in)
10 years61.7 mm (2.4 in)
25 years72.1 mm (2.8 in)
50 years79.9 mm (3.1 in)
100 years87.9 mm (3.5 in)Longer than the 53 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, 53 years of values from 1883 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: 77.0 mm (3.0 in) in 1924; 70.9 mm (2.8 in) in 1968; 70.4 mm (2.8 in) in 1922.

Station Changes

No change in the annual mean temperature of this station was found against its neighbours.

Download the Data

  • Data for St Catharines standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for St Catharines 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.

Data as of . Last revised (2026-10-14).