Toronto Lester B. Pearson Int' Weather Records (CA006158733)
Record envelope, standing records and threshold days for Toronto Lester B. Pearson Int' (CA006158733), Ontario, Canada, with 77 years of record.
Key Facts for Toronto Lester B. Pearson Int'
- Toronto Lester B. Pearson Int' (CA006158733) is a weather station in Ontario, Canada at 43.68 latitude and -79.63 longitude, 173 m (568 ft) above sea level.
- The station reports from 1937 to 2013, 77 years of record.
- 1,464 records set at Toronto Lester B. Pearson Int' still stand.
- Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
- Toronto Lester B. Pearson Int' set a daily record snowfall of 16.3 cm (6.4 in) on 28 December 1983.
About the Station
- Location: Ontario, Canada, 43.68 latitude, -79.63 longitude.
- Elevation: 173 m (568 ft).
- Period of record: 1937 to 2013, 77 years.
- Eligible elements: tmax, tmin, prcp, snow.
Daily Record Envelope and 2026
0 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 16.7 C (62.1 F) | -31.3 C (-24.3 F) | n/a | n/a |
| Feb | 12.2 C (54.0 F) | -31.1 C (-24.0 F) | n/a | n/a |
| Mar | 25.6 C (78.1 F) | -28.9 C (-20.0 F) | n/a | n/a |
| Apr | 29.4 C (84.9 F) | -17.2 C (1.0 F) | n/a | n/a |
| May | 34.4 C (93.9 F) | -5.6 C (21.9 F) | n/a | n/a |
| Jun | 36.7 C (98.1 F) | 0.6 C (33.1 F) | n/a | n/a |
| Jul | 36.1 C (97.0 F) | 3.9 C (39.0 F) | n/a | n/a |
| Aug | 38.3 C (100.9 F) | 1.1 C (34.0 F) | n/a | n/a |
| Sep | 36.7 C (98.1 F) | -3.9 C (25.0 F) | n/a | n/a |
| Oct | 30.6 C (87.1 F) | -8.3 C (17.1 F) | n/a | n/a |
| Nov | 25.0 C (77.0 F) | -18.3 C (-0.9 F) | n/a | n/a |
| Dec | 20.0 C (68.0 F) | -31.1 C (-24.0 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1937 | 4 |
| 1938 | 43 |
| 1939 | 18 |
| 1940 | 47 |
| 1941 | 33 |
| 1942 | 31 |
| 1943 | 36 |
| 1944 | 27 |
| 1945 | 43 |
| 1946 | 39 |
| 1947 | 34 |
| 1948 | 41 |
| 1949 | 55 |
| 1950 | 41 |
| 1951 | 30 |
| 1952 | 29 |
| 1953 | 28 |
| 1954 | 30 |
| 1955 | 46 |
| 1956 | 38 |
| 1957 | 31 |
| 1958 | 16 |
| 1959 | 46 |
| 1960 | 22 |
| 1961 | 14 |
| 1962 | 27 |
| 1963 | 34 |
| 1964 | 39 |
| 1965 | 53 |
| 1966 | 25 |
| 1967 | 37 |
| 1968 | 30 |
| 1969 | 19 |
| 1970 | 18 |
| 1971 | 16 |
| 1972 | 32 |
| 1973 | 31 |
| 1974 | 26 |
| 1975 | 27 |
| 1976 | 42 |
| 1977 | 27 |
| 1978 | 13 |
| 1979 | 42 |
| 1980 | 25 |
| 1981 | 32 |
| 1982 | 26 |
| 1983 | 21 |
All-Time Record Progression
4 new records| Date | Kind | Detail |
|---|---|---|
| 1979-02-17 | Record low maximum temperature | Record low maximum temperature -19.2 C (-2.6 F) |
| 1981-01-03 | Record low maximum temperature | Record low maximum temperature -19.7 C (-3.5 F) |
| 1981-01-04 | Record low minimum temperature | Record low minimum temperature -31.3 C (-24.3 F) |
| 1981-01-11 | Record low maximum temperature | Record low maximum temperature -19.8 C (-3.6 F) |
Wettest Day of Each Month
Oct: 121.4 mm (4.8 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 58.7 mm (2.3 in) | 9 January 1946 |
| Feb | 55.9 mm (2.2 in) | 25 February 1965 |
| Mar | 41.7 mm (1.6 in) | 16 March 1942 |
| Apr | 41.7 mm (1.6 in) | 12 April 1951 |
| May | 92.7 mm (3.6 in) | 31 May 1944 |
| Jun | 43.9 mm (1.7 in) | 28 June 1957 |
| Jul | 118.5 mm (4.7 in) | 28 July 1980 |
| Aug | 80.8 mm (3.2 in) | 30 August 1970 |
| Sep | 108.0 mm (4.3 in) | 18 September 1948 |
| Oct | 121.4 mm (4.8 in) | 15 October 1954 |
| Nov | 86.1 mm (3.4 in) | 10 November 1962 |
| Dec | 40.9 mm (1.6 in) | 6 December 1962 |
Period of Record Coverage
1937 to 1983| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1937 | 57 | 16% | No |
| 1938 | 362 | 99% | Yes |
| 1939 | 243 | 67% | No |
| 1940 | 366 | 100% | Yes |
| 1941 | 365 | 100% | Yes |
| 1942 | 365 | 100% | Yes |
| 1943 | 365 | 100% | Yes |
| 1944 | 366 | 100% | Yes |
| 1945 | 365 | 100% | Yes |
| 1946 | 364 | 100% | Yes |
| 1947 | 365 | 100% | Yes |
| 1948 | 366 | 100% | Yes |
| 1949 | 365 | 100% | Yes |
| 1950 | 365 | 100% | Yes |
| 1951 | 365 | 100% | Yes |
| 1952 | 366 | 100% | Yes |
| 1953 | 365 | 100% | Yes |
| 1954 | 365 | 100% | Yes |
| 1955 | 365 | 100% | Yes |
| 1956 | 366 | 100% | Yes |
| 1957 | 365 | 100% | Yes |
| 1958 | 365 | 100% | Yes |
| 1959 | 365 | 100% | Yes |
| 1960 | 366 | 100% | Yes |
| 1961 | 365 | 100% | Yes |
| 1962 | 365 | 100% | Yes |
| 1963 | 365 | 100% | Yes |
| 1964 | 366 | 100% | Yes |
| 1965 | 365 | 100% | Yes |
| 1966 | 365 | 100% | Yes |
| 1967 | 365 | 100% | Yes |
| 1968 | 366 | 100% | Yes |
| 1969 | 365 | 100% | Yes |
| 1970 | 365 | 100% | Yes |
| 1971 | 365 | 100% | Yes |
| 1972 | 366 | 100% | Yes |
| 1973 | 365 | 100% | Yes |
| 1974 | 365 | 100% | Yes |
| 1975 | 365 | 100% | Yes |
| 1976 | 366 | 100% | Yes |
| 1977 | 365 | 100% | Yes |
| 1978 | 365 | 100% | Yes |
| 1979 | 365 | 100% | Yes |
| 1980 | 366 | 100% | Yes |
| 1981 | 365 | 100% | Yes |
| 1982 | 365 | 100% | Yes |
| 1983 | 365 | 100% | Yes |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 28 December 1983 | Toronto Lester B. Pearson Int', CA | daily snowfall | 16.3 cm (6.4 in) | 3.6 cm (1.4 in) | 14 years | 17 of 100 (Routine) |
| 26 December 1983 | Toronto Lester B. Pearson Int', CA | daily low min (Tie) | -18.9 C (-2.0 F) | tie | 34 years | 3 of 100 (Routine) |
| 24 December 1983 | Toronto Lester B. Pearson Int', CA | daily low max | -13.1 C (8.4 F) | 0.3 C (0.5 F) | 13 years | 8 of 100 (Routine) |
| 21 December 1983 | Toronto Lester B. Pearson Int', CA | daily snowfall | 4.6 cm (1.8 in) | 1.0 cm (0.4 in) | 40 years | 18 of 100 (Routine) |
| 19 December 1983 | Toronto Lester B. Pearson Int', CA | daily low max | -11.2 C (11.8 F) | 1.2 C (2.2 F) | 40 years | 18 of 100 (Routine) |
| 16 November 1983 | Toronto Lester B. Pearson Int', CA | daily snowfall | 3.4 cm (1.3 in) | 0.1 cm (0.0 in) | 14 years | 8 of 100 (Routine) |
| 13 November 1983 | Toronto Lester B. Pearson Int', CA | daily low max | -2.0 C (28.4 F) | 0.9 C (1.6 F) | 40 years | 17 of 100 (Routine) |
| 13 November 1983 | Toronto Lester B. Pearson Int', CA | daily low min | -8.5 C (16.7 F) | 2.2 C (4.0 F) | 5 years | 9 of 100 (Routine) |
| 12 November 1983 | Toronto Lester B. Pearson Int', CA | daily low max | -0.4 C (31.3 F) | 0.2 C (0.4 F) | 5 years | 5 of 100 (Routine) |
| 11 November 1983 | Toronto Lester B. Pearson Int', CA | daily snowfall | 3.0 cm (1.2 in) | 2.6 cm (1.0 in) | 2 years | 9 of 100 (Routine) |
| 9 November 1983 | Toronto Lester B. Pearson Int', CA | daily high max | 16.0 C (60.8 F) | 0.4 C (0.7 F) | 34 years | 14 of 100 (Routine) |
| 4 November 1983 | Toronto Lester B. Pearson Int', CA | daily snowfall | 3.8 cm (1.5 in) | 1.3 cm (0.5 in) | 32 years | 15 of 100 (Routine) |
| 12 October 1983 | Toronto Lester B. Pearson Int', CA | daily rain | 19.3 mm (0.8 in) | 3.6 mm (0.14 in) | 36 years | 18 of 100 (Routine) |
| 3 October 1983 | Toronto Lester B. Pearson Int', CA | daily high min | 15.6 C (60.1 F) | 0.6 C (1.1 F) | 12 years | 8 of 100 (Routine) |
| 16 September 1983 | Toronto Lester B. Pearson Int', CA | daily rain | 28.9 mm (1.1 in) | 12.6 mm (0.5 in) | 5 years | 17 of 100 (Routine) |
| 10 September 1983 | Toronto Lester B. Pearson Int', CA | daily high max | 34.2 C (93.6 F) | 0.9 C (1.6 F) | 30 years | 14 of 100 (Routine) |
| 11 August 1983 | Toronto Lester B. Pearson Int', CA | daily low max | 18.2 C (64.8 F) | 1.2 C (2.2 F) | 32 years | 16 of 100 (Routine) |
| 16 July 1983 | Toronto Lester B. Pearson Int', CA | daily high max | 34.5 C (94.1 F) | 1.2 C (2.2 F) | 14 years | 11 of 100 (Routine) |
| 15 July 1983 | Toronto Lester B. Pearson Int', CA | daily high max | 35.7 C (96.3 F) | 2.3 C (4.1 F) | 5 years | 11 of 100 (Routine) |
| 23 June 1983 | Toronto Lester B. Pearson Int', CA | daily high max | 32.8 C (91.0 F) | 0.6 C (1.1 F) | 34 years | 15 of 100 (Routine) |
Climate Trend
45 complete years, 1938 to 1983| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1938 | 8.1 C | +0.78 C |
| 1940 | 6.0 C | -1.26 C |
| 1941 | 8.1 C | +0.75 C |
| 1942 | 7.5 C | +0.16 C |
| 1943 | 6.5 C | -0.77 C |
| 1944 | 7.5 C | +0.24 C |
| 1945 | 6.8 C | -0.48 C |
| 1946 | 8.0 C | +0.71 C |
| 1947 | 7.5 C | +0.15 C |
| 1948 | 7.5 C | +0.17 C |
| 1949 | 8.7 C | +1.41 C |
| 1950 | 7.0 C | -0.33 C |
| 1951 | 7.6 C | +0.34 C |
| 1952 | 8.4 C | +1.06 C |
| 1953 | 8.8 C | +1.54 C |
| 1954 | 7.7 C | +0.43 C |
| 1955 | 8.5 C | +1.19 C |
| 1956 | 7.1 C | -0.21 C |
| 1957 | 8.0 C | +0.69 C |
| 1958 | 7.5 C | +0.15 C |
| 1959 | 8.3 C | +0.99 C |
| 1960 | 7.7 C | +0.36 C |
| 1961 | 8.1 C | +0.76 C |
| 1962 | 7.4 C | +0.08 C |
| 1963 | 7.3 C | -0.01 C |
| 1964 | 7.1 C | -0.17 C |
| 1965 | 6.4 C | -0.91 C |
| 1966 | 6.9 C | -0.43 C |
| 1967 | 6.5 C | -0.78 C |
| 1968 | 6.7 C | -0.63 C |
| 1969 | 6.9 C | -0.43 C |
| 1970 | 6.7 C | -0.58 C |
| 1971 | 7.1 C | -0.25 C |
| 1972 | 5.9 C | -1.38 C |
| 1973 | 7.9 C | +0.62 C |
| 1974 | 6.8 C | -0.52 C |
| 1975 | 7.7 C | +0.39 C |
| 1976 | 6.2 C | -1.10 C |
| 1977 | 7.0 C | -0.30 C |
| 1978 | 6.2 C | -1.10 C |
| 1979 | 6.8 C | -0.47 C |
| 1980 | 6.6 C | -0.68 C |
| 1981 | 7.1 C | -0.17 C |
| 1982 | 6.8 C | -0.49 C |
| 1983 | 7.8 C | +0.45 C |
The annual mean temperature here has fallen by 0.2 C (0.1 to 0.4) per decade over 1938 to 1983. In Fahrenheit: 0.4 F (0.1 to 0.7) per decade. The slope is a straight line fitted to 45 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | -0.2 C (-0.4 to -0.1) per decade | -0.4 F (-0.7 to -0.1) per decade | 1938 to 1983 | 45 | Fall |
| Mean daily maximum | -0.21 C (-0.37 to -0.04) per decade | -0.4 F (-0.7 to -0.1) per decade | 1938 to 1983 | 45 | Fall |
| Mean daily minimum | -0.22 C (-0.38 to -0.05) per decade | -0.4 F (-0.7 to -0.1) per decade | 1938 to 1983 | 45 | Fall |
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
1937 to 1983| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 38.3 C (100.9 F) | 1948 | 34.3 C (93.7 F) | 47 |
| Coldest night (TNn) | -31.3 C (-24.3 F) | 1981 | -25.0 C (-13.0 F) | 47 |
| Wettest day (Rx1day) | 121.4 mm (4.8 in) | 1954 | 42.7 mm (1.7 in) | 47 |
| Wettest five days (Rx5day) | 161.1 mm (6.3 in) | 1954 | 69.6 mm (2.7 in) | 47 |
| Longest dry spell (CDD) | 40 days | 1966 | 18 days | 47 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1937 | 18.3 C (64.9 F) |
| 1938 | 36.1 C (97.0 F) |
| 1939 | 34.4 C (93.9 F) |
| 1940 | 32.8 C (91.0 F) |
| 1941 | 36.1 C (97.0 F) |
| 1942 | 34.4 C (93.9 F) |
| 1943 | 34.4 C (93.9 F) |
| 1944 | 36.1 C (97.0 F) |
| 1945 | 33.3 C (91.9 F) |
| 1946 | 35.6 C (96.1 F) |
| 1947 | 35.6 C (96.1 F) |
| 1948 | 38.3 C (100.9 F) |
| 1949 | 37.2 C (99.0 F) |
| 1950 | 32.2 C (90.0 F) |
| 1951 | 32.2 C (90.0 F) |
| 1952 | 36.7 C (98.1 F) |
| 1953 | 36.7 C (98.1 F) |
| 1954 | 32.8 C (91.0 F) |
| 1955 | 36.7 C (98.1 F) |
| 1956 | 33.9 C (93.0 F) |
| 1957 | 34.4 C (93.9 F) |
| 1958 | 32.8 C (91.0 F) |
| 1959 | 35.0 C (95.0 F) |
| 1960 | 33.9 C (93.0 F) |
| 1961 | 33.3 C (91.9 F) |
| 1962 | 34.4 C (93.9 F) |
| 1963 | 35.6 C (96.1 F) |
| 1964 | 35.0 C (95.0 F) |
| 1965 | 33.3 C (91.9 F) |
| 1966 | 35.0 C (95.0 F) |
| 1967 | 31.1 C (88.0 F) |
| 1968 | 33.3 C (91.9 F) |
| 1969 | 33.9 C (93.0 F) |
| 1970 | 32.2 C (90.0 F) |
| 1971 | 32.8 C (91.0 F) |
| 1972 | 32.8 C (91.0 F) |
| 1973 | 35.6 C (96.1 F) |
| 1974 | 33.3 C (91.9 F) |
| 1975 | 36.1 C (97.0 F) |
| 1976 | 31.7 C (89.1 F) |
| 1977 | 34.3 C (93.7 F) |
| 1978 | 35.8 C (96.4 F) |
| 1979 | 30.9 C (87.6 F) |
| 1980 | 31.9 C (89.4 F) |
| 1981 | 32.8 C (91.0 F) |
| 1982 | 33.0 C (91.4 F) |
| 1983 | 35.7 C (96.3 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1937 | -20.0 C (-4.0 F) |
| 1938 | -27.2 C (-17.0 F) |
| 1939 | -29.4 C (-20.9 F) |
| 1940 | -26.1 C (-15.0 F) |
| 1941 | -25.6 C (-14.1 F) |
| 1942 | -31.1 C (-24.0 F) |
| 1943 | -31.1 C (-24.0 F) |
| 1944 | -28.3 C (-18.9 F) |
| 1945 | -29.4 C (-20.9 F) |
| 1946 | -24.4 C (-11.9 F) |
| 1947 | -20.0 C (-4.0 F) |
| 1948 | -28.3 C (-18.9 F) |
| 1949 | -20.0 C (-4.0 F) |
| 1950 | -28.9 C (-20.0 F) |
| 1951 | -26.1 C (-15.0 F) |
| 1952 | -23.3 C (-9.9 F) |
| 1953 | -18.3 C (-0.9 F) |
| 1954 | -23.3 C (-9.9 F) |
| 1955 | -25.0 C (-13.0 F) |
| 1956 | -20.0 C (-4.0 F) |
| 1957 | -24.4 C (-11.9 F) |
| 1958 | -24.4 C (-11.9 F) |
| 1959 | -25.6 C (-14.1 F) |
| 1960 | -22.8 C (-9.0 F) |
| 1961 | -25.0 C (-13.0 F) |
| 1962 | -23.3 C (-9.9 F) |
| 1963 | -24.4 C (-11.9 F) |
| 1964 | -22.8 C (-9.0 F) |
| 1965 | -23.9 C (-11.0 F) |
| 1966 | -26.1 C (-15.0 F) |
| 1967 | -26.7 C (-16.1 F) |
| 1968 | -26.7 C (-16.1 F) |
| 1969 | -20.6 C (-5.1 F) |
| 1970 | -27.8 C (-18.0 F) |
| 1971 | -23.9 C (-11.0 F) |
| 1972 | -23.9 C (-11.0 F) |
| 1973 | -22.8 C (-9.0 F) |
| 1974 | -21.7 C (-7.1 F) |
| 1975 | -24.4 C (-11.9 F) |
| 1976 | -31.1 C (-24.0 F) |
| 1977 | -28.6 C (-19.5 F) |
| 1978 | -22.6 C (-8.7 F) |
| 1979 | -27.7 C (-17.9 F) |
| 1980 | -27.6 C (-17.7 F) |
| 1981 | -31.3 C (-24.3 F) |
| 1982 | -26.4 C (-15.5 F) |
| 1983 | -22.0 C (-7.6 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1937 | 9.9 mm (0.39 in) |
| 1938 | 41.9 mm (1.6 in) |
| 1939 | 44.5 mm (1.8 in) |
| 1940 | 33.5 mm (1.3 in) |
| 1941 | 40.4 mm (1.6 in) |
| 1942 | 50.3 mm (2.0 in) |
| 1943 | 42.7 mm (1.7 in) |
| 1944 | 92.7 mm (3.6 in) |
| 1945 | 46.2 mm (1.8 in) |
| 1946 | 58.7 mm (2.3 in) |
| 1947 | 40.6 mm (1.6 in) |
| 1948 | 108.0 mm (4.3 in) |
| 1949 | 43.7 mm (1.7 in) |
| 1950 | 39.4 mm (1.6 in) |
| 1951 | 41.7 mm (1.6 in) |
| 1952 | 35.8 mm (1.4 in) |
| 1953 | 48.5 mm (1.9 in) |
| 1954 | 121.4 mm (4.8 in) |
| 1955 | 58.7 mm (2.3 in) |
| 1956 | 46.5 mm (1.8 in) |
| 1957 | 54.1 mm (2.1 in) |
| 1958 | 32.3 mm (1.3 in) |
| 1959 | 28.7 mm (1.1 in) |
| 1960 | 43.9 mm (1.7 in) |
| 1961 | 33.5 mm (1.3 in) |
| 1962 | 86.1 mm (3.4 in) |
| 1963 | 38.4 mm (1.5 in) |
| 1964 | 54.9 mm (2.2 in) |
| 1965 | 55.9 mm (2.2 in) |
| 1966 | 39.1 mm (1.5 in) |
| 1967 | 37.8 mm (1.5 in) |
| 1968 | 66.8 mm (2.6 in) |
| 1969 | 49.3 mm (1.9 in) |
| 1970 | 80.8 mm (3.2 in) |
| 1971 | 36.6 mm (1.4 in) |
| 1972 | 35.1 mm (1.4 in) |
| 1973 | 39.6 mm (1.6 in) |
| 1974 | 53.1 mm (2.1 in) |
| 1975 | 31.8 mm (1.3 in) |
| 1976 | 36.6 mm (1.4 in) |
| 1977 | 49.4 mm (1.9 in) |
| 1978 | 38.0 mm (1.5 in) |
| 1979 | 40.2 mm (1.6 in) |
| 1980 | 118.5 mm (4.7 in) |
| 1981 | 36.4 mm (1.4 in) |
| 1982 | 57.1 mm (2.2 in) |
| 1983 | 29.6 mm (1.2 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1937 | 16.7 mm (0.7 in) |
| 1938 | 77.7 mm (3.1 in) |
| 1939 | 48.3 mm (1.9 in) |
| 1940 | 60.1 mm (2.4 in) |
| 1941 | 41.7 mm (1.6 in) |
| 1942 | 78.7 mm (3.1 in) |
| 1943 | 57.4 mm (2.3 in) |
| 1944 | 115.3 mm (4.5 in) |
| 1945 | 74.8 mm (2.9 in) |
| 1946 | 68.1 mm (2.7 in) |
| 1947 | 70.4 mm (2.8 in) |
| 1948 | 135.9 mm (5.4 in) |
| 1949 | 89.5 mm (3.5 in) |
| 1950 | 69.3 mm (2.7 in) |
| 1951 | 61.5 mm (2.4 in) |
| 1952 | 72.7 mm (2.9 in) |
| 1953 | 62.7 mm (2.5 in) |
| 1954 | 161.1 mm (6.3 in) |
| 1955 | 77.5 mm (3.1 in) |
| 1956 | 61.4 mm (2.4 in) |
| 1957 | 86.1 mm (3.4 in) |
| 1958 | 51.9 mm (2.0 in) |
| 1959 | 48.8 mm (1.9 in) |
| 1960 | 69.6 mm (2.7 in) |
| 1961 | 36.8 mm (1.4 in) |
| 1962 | 89.1 mm (3.5 in) |
| 1963 | 45.5 mm (1.8 in) |
| 1964 | 77.2 mm (3.0 in) |
| 1965 | 62.5 mm (2.5 in) |
| 1966 | 67.3 mm (2.6 in) |
| 1967 | 62.9 mm (2.5 in) |
| 1968 | 93.7 mm (3.7 in) |
| 1969 | 95.1 mm (3.7 in) |
| 1970 | 81.6 mm (3.2 in) |
| 1971 | 55.8 mm (2.2 in) |
| 1972 | 54.4 mm (2.1 in) |
| 1973 | 90.2 mm (3.6 in) |
| 1974 | 85.1 mm (3.4 in) |
| 1975 | 54.1 mm (2.1 in) |
| 1976 | 62.0 mm (2.4 in) |
| 1977 | 68.9 mm (2.7 in) |
| 1978 | 73.4 mm (2.9 in) |
| 1979 | 79.0 mm (3.1 in) |
| 1980 | 124.2 mm (4.9 in) |
| 1981 | 73.8 mm (2.9 in) |
| 1982 | 72.0 mm (2.8 in) |
| 1983 | 55.4 mm (2.2 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1937 | 13 days |
| 1938 | 26 days |
| 1939 | 18 days |
| 1940 | 11 days |
| 1941 | 16 days |
| 1942 | 15 days |
| 1943 | 28 days |
| 1944 | 15 days |
| 1945 | 10 days |
| 1946 | 24 days |
| 1947 | 21 days |
| 1948 | 14 days |
| 1949 | 27 days |
| 1950 | 15 days |
| 1951 | 17 days |
| 1952 | 17 days |
| 1953 | 15 days |
| 1954 | 19 days |
| 1955 | 22 days |
| 1956 | 30 days |
| 1957 | 22 days |
| 1958 | 16 days |
| 1959 | 16 days |
| 1960 | 34 days |
| 1961 | 23 days |
| 1962 | 23 days |
| 1963 | 27 days |
| 1964 | 15 days |
| 1965 | 20 days |
| 1966 | 40 days |
| 1967 | 21 days |
| 1968 | 24 days |
| 1969 | 25 days |
| 1970 | 17 days |
| 1971 | 14 days |
| 1972 | 14 days |
| 1973 | 21 days |
| 1974 | 16 days |
| 1975 | 14 days |
| 1976 | 20 days |
| 1977 | 22 days |
| 1978 | 17 days |
| 1979 | 17 days |
| 1980 | 16 days |
| 1981 | 19 days |
| 1982 | 17 days |
| 1983 | 19 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
45 years with a frostAcross 45 years with a frost, the median last spring frost at Toronto Lester B. Pearson Int' falls on 8 May and the median first autumn frost on 4 October, which leaves a median of 150 days between them.
Fitted over all years, the growing season changes by +1.1 days per decade at this station.
| Measure | Median, all years | Earliest period | Recent period (1954 to 1983) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 8 May | n/a | 8 May | n/a | -0.5 days per decade |
| First autumn frost | 4 October | n/a | 6 October | n/a | +0.6 days per decade |
| Growing days | 150 days | n/a | 152 days | n/a | +1.1 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
45 years, 1938 to 1983A day with at least 43.8 mm (1.7 in) of rain is expected about once in 2 years. A day with at least 155.4 mm (6.1 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 43.8 mm (1.7 in) | |
| 5 years | 59.6 mm (2.3 in) | |
| 10 years | 74.1 mm (2.9 in) | |
| 25 years | 99.1 mm (3.9 in) | |
| 50 years | 123.8 mm (4.9 in) | Longer than the 45 years of record |
| 100 years | 155.4 mm (6.1 in) | Longer than the 45 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, 45 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: 121.4 mm (4.8 in) in 1954; 118.5 mm (4.7 in) in 1980; 108.0 mm (4.3 in) in 1948.
Station Changes
2 suspected2 changes were suspected in the annual mean temperature of Toronto Lester B. Pearson Int', at 1958 and 1964. Each is measured against neighbouring stations.
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1958 ran 0.5 C (0.8 F) higher than in the years before (likely change).
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1964 ran 0.6 C (1.0 F) lower than in the years before (likely change).
| Year | Shift (C) | Shift (F) | Strength | Neighbours |
|---|---|---|---|---|
| 1958 | +0.5 | +0.8 | likely | 5 |
| 1964 | -0.6 | -1.0 | likely | 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
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).