Great Falls Weather Records (CA005031200)
Record envelope, standing records and threshold days for Great Falls (CA005031200), Manitoba, Canada, with 82 years of record.
Key Facts for Great Falls
- Great Falls (CA005031200) is a weather station in Manitoba, Canada at 50.47 latitude and -96.00 longitude, 249 m (817 ft) above sea level.
- The station reports from 1922 to 2003, 82 years of record.
- 1,464 records set at Great Falls still stand.
- Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
- Great Falls set a daily record low maximum temperature of -24.5 C (-12.1 F) on 22 December 1983.
About the Station
- Location: Manitoba, Canada, 50.47 latitude, -96.00 longitude.
- Elevation: 249 m (817 ft).
- Period of record: 1922 to 2003, 82 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 | 6.1 C (43.0 F) | -45.6 C (-50.1 F) | n/a | n/a |
| Feb | 11.1 C (52.0 F) | -45.6 C (-50.1 F) | n/a | n/a |
| Mar | 22.2 C (72.0 F) | -38.3 C (-36.9 F) | n/a | n/a |
| Apr | 34.0 C (93.2 F) | -31.7 C (-25.1 F) | n/a | n/a |
| May | 36.0 C (96.8 F) | -13.3 C (8.1 F) | n/a | n/a |
| Jun | 37.2 C (99.0 F) | -3.3 C (26.1 F) | n/a | n/a |
| Jul | 40.0 C (104.0 F) | 3.9 C (39.0 F) | n/a | n/a |
| Aug | 38.9 C (102.0 F) | -2.2 C (28.0 F) | n/a | n/a |
| Sep | 35.5 C (95.9 F) | -6.1 C (21.0 F) | n/a | n/a |
| Oct | 30.6 C (87.1 F) | -16.7 C (1.9 F) | n/a | n/a |
| Nov | 22.2 C (72.0 F) | -32.8 C (-27.0 F) | n/a | n/a |
| Dec | 8.3 C (46.9 F) | -43.9 C (-47.0 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1922 | 9 |
| 1923 | 58 |
| 1924 | 25 |
| 1925 | 18 |
| 1926 | 18 |
| 1927 | 19 |
| 1928 | 26 |
| 1929 | 14 |
| 1930 | 21 |
| 1931 | 27 |
| 1932 | 43 |
| 1933 | 43 |
| 1934 | 35 |
| 1935 | 33 |
| 1936 | 60 |
| 1937 | 15 |
| 1938 | 21 |
| 1939 | 22 |
| 1940 | 18 |
| 1941 | 30 |
| 1942 | 24 |
| 1943 | 16 |
| 1944 | 13 |
| 1945 | 29 |
| 1946 | 21 |
| 1947 | 23 |
| 1948 | 9 |
| 1949 | 28 |
| 1950 | 33 |
| 1951 | 17 |
| 1952 | 28 |
| 1953 | 29 |
| 1954 | 17 |
| 1955 | 17 |
| 1956 | 22 |
| 1957 | 8 |
| 1958 | 31 |
| 1959 | 18 |
| 1960 | 14 |
| 1961 | 17 |
| 1962 | 22 |
| 1963 | 31 |
| 1964 | 29 |
| 1965 | 14 |
| 1966 | 20 |
| 1967 | 24 |
| 1968 | 24 |
| 1969 | 19 |
| 1970 | 20 |
| 1971 | 12 |
| 1972 | 28 |
| 1973 | 11 |
| 1974 | 20 |
| 1975 | 19 |
| 1976 | 19 |
| 1977 | 42 |
| 1978 | 14 |
| 1979 | 25 |
| 1980 | 24 |
| 1981 | 25 |
| 1982 | 18 |
| 1983 | 35 |
All-Time Record Progression
3 new records| Date | Kind | Detail |
|---|---|---|
| 1955-12-20 | Record daily snowfall | Record daily snowfall 35.6 cm (14.0 in) |
| 1972-01-14 | Record low maximum temperature | Record low maximum temperature -33.9 C (-29.0 F) |
| 1973-06-14 | Record daily precipitation | Record daily precipitation 73.9 mm (2.9 in) |
Wettest Day of Each Month
Jun: 73.9 mm (2.9 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 27.9 mm (1.1 in) | 23 January 1943 |
| Feb | 25.4 mm (1.0 in) | 12 February 1961 |
| Mar | 27.9 mm (1.1 in) | 5 March 1944 |
| Apr | 24.9 mm (1.0 in) | 28 April 1954 |
| May | 49.0 mm (1.9 in) | 19 May 1974 |
| Jun | 73.9 mm (2.9 in) | 14 June 1973 |
| Jul | 59.4 mm (2.3 in) | 2 July 1935 |
| Aug | 55.4 mm (2.2 in) | 30 August 1944 |
| Sep | 61.5 mm (2.4 in) | 3 September 1941 |
| Oct | 49.8 mm (2.0 in) | 10 October 1949 |
| Nov | 22.9 mm (0.9 in) | 15 November 1955 |
| Dec | 35.6 mm (1.4 in) | 20 December 1955 |
Period of Record Coverage
1922 to 1983| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1922 | 122 | 33% | No |
| 1923 | 364 | 100% | Yes |
| 1924 | 364 | 99% | Yes |
| 1925 | 198 | 54% | No |
| 1926 | 307 | 84% | No |
| 1927 | 365 | 100% | Yes |
| 1928 | 366 | 100% | Yes |
| 1929 | 365 | 100% | Yes |
| 1930 | 365 | 100% | Yes |
| 1931 | 365 | 100% | Yes |
| 1932 | 335 | 92% | Yes |
| 1933 | 365 | 100% | Yes |
| 1934 | 365 | 100% | Yes |
| 1935 | 365 | 100% | Yes |
| 1936 | 366 | 100% | Yes |
| 1937 | 365 | 100% | Yes |
| 1938 | 365 | 100% | Yes |
| 1939 | 365 | 100% | Yes |
| 1940 | 366 | 100% | Yes |
| 1941 | 365 | 100% | Yes |
| 1942 | 363 | 99% | Yes |
| 1943 | 365 | 100% | Yes |
| 1944 | 366 | 100% | Yes |
| 1945 | 365 | 100% | Yes |
| 1946 | 365 | 100% | Yes |
| 1947 | 364 | 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 | 364 | 100% | Yes |
| 1955 | 365 | 100% | Yes |
| 1956 | 336 | 92% | Yes |
| 1957 | 365 | 100% | Yes |
| 1958 | 364 | 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 | 360 | 99% | Yes |
| 1978 | 360 | 99% | Yes |
| 1979 | 365 | 100% | Yes |
| 1980 | 364 | 99% | Yes |
| 1981 | 333 | 91% | Yes |
| 1982 | 333 | 91% | Yes |
| 1983 | 363 | 99% | Yes |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 22 December 1983 | Great Falls, CA | daily low max | -24.5 C (-12.1 F) | 3.9 C (7.0 F) | 37 years | 22 of 100 (Routine) |
| 18 December 1983 | Great Falls, CA | daily low max (Tie) | -25.0 C (-13.0 F) | tie | 32 years | 3 of 100 (Routine) |
| 16 December 1983 | Great Falls, CA | daily low max | -23.5 C (-10.3 F) | 0.2 C (0.4 F) | 58 years | 23 of 100 (Routine) |
| 19 November 1983 | Great Falls, CA | daily high min | 2.0 C (35.6 F) | 2.0 C (3.6 F) | 46 years | 22 of 100 (Routine) |
| 1 November 1983 | Great Falls, CA | daily high min | 9.0 C (48.2 F) | 3.4 C (6.1 F) | 36 years | 20 of 100 (Routine) |
| 23 October 1983 | Great Falls, CA | daily rain | 14.0 mm (0.6 in) | 12.2 mm (0.5 in) | 2 years | 20 of 100 (Routine) |
| 27 September 1983 | Great Falls, CA | daily high min | 14.5 C (58.1 F) | 1.7 C (3.1 F) | 60 years | 27 of 100 (Routine) |
| 22 September 1983 | Great Falls, CA | daily low max | 7.0 C (44.6 F) | 0.8 C (1.4 F) | 54 years | 23 of 100 (Routine) |
| 2 September 1983 | Great Falls, CA | monthly high max | 35.5 C (95.9 F) | 1.6 C (2.9 F) | 42 years | 30 of 100 (Routine) |
| 1 September 1983 | Great Falls, CA | monthly high min | 22.0 C (71.6 F) | 0.9 C (1.6 F) | 34 years | 27 of 100 (Routine) |
| 17 August 1983 | Great Falls, CA | daily high max | 32.0 C (89.6 F) | 0.9 C (1.6 F) | 48 years | 22 of 100 (Routine) |
| 4 August 1983 | Great Falls, CA | daily high max | 37.0 C (98.6 F) | 3.1 C (5.6 F) | 52 years | 27 of 100 (Routine) |
| 4 August 1983 | Great Falls, CA | daily high min | 22.0 C (71.6 F) | 0.3 C (0.5 F) | 36 years | 16 of 100 (Routine) |
| 15 July 1983 | Great Falls, CA | daily high min | 24.5 C (76.1 F) | 3.4 C (6.1 F) | 8 years | 18 of 100 (Routine) |
| 15 July 1983 | Great Falls, CA | daily high max | 34.5 C (94.1 F) | 0.1 C (0.2 F) | 36 years | 16 of 100 (Routine) |
| 5 July 1983 | Great Falls, CA | daily low min | 5.0 C (41.0 F) | 0.6 C (1.1 F) | 48 years | 21 of 100 (Routine) |
| 4 July 1983 | Great Falls, CA | daily low max | 16.0 C (60.8 F) | 0.1 C (0.2 F) | 26 years | 14 of 100 (Routine) |
| 21 June 1983 | Great Falls, CA | daily rain | 40.0 mm (1.6 in) | 20.9 mm (0.8 in) | 8 years | 31 of 100 (Routine) |
| 15 June 1983 | Great Falls, CA | daily low max | 12.0 C (53.6 F) | 0.2 C (0.4 F) | 44 years | 19 of 100 (Routine) |
| 12 June 1983 | Great Falls, CA | daily high min | 18.0 C (64.4 F) | 0.2 C (0.4 F) | 32 years | 15 of 100 (Routine) |
Climate Trend
55 complete years, 1923 to 1983| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1923 | 2.7 C | +0.51 C |
| 1924 | 1.9 C | -0.31 C |
| 1927 | 1.8 C | -0.40 C |
| 1928 | 2.9 C | +0.68 C |
| 1929 | 0.6 C | -1.58 C |
| 1930 | 2.3 C | +0.09 C |
| 1931 | 4.5 C | +2.37 C |
| 1933 | 0.9 C | -1.24 C |
| 1934 | 1.7 C | -0.44 C |
| 1935 | 1.4 C | -0.75 C |
| 1936 | 0.4 C | -1.78 C |
| 1937 | 1.4 C | -0.76 C |
| 1938 | 2.9 C | +0.75 C |
| 1939 | 2.5 C | +0.28 C |
| 1940 | 2.9 C | +0.74 C |
| 1941 | 3.5 C | +1.34 C |
| 1942 | 2.7 C | +0.55 C |
| 1943 | 1.8 C | -0.39 C |
| 1944 | 3.3 C | +1.10 C |
| 1945 | 1.6 C | -0.60 C |
| 1946 | 2.0 C | -0.19 C |
| 1947 | 1.8 C | -0.39 C |
| 1948 | 2.4 C | +0.26 C |
| 1949 | 1.9 C | -0.27 C |
| 1950 | -0.4 C | -2.59 C |
| 1951 | 1.0 C | -1.15 C |
| 1952 | 3.2 C | +1.07 C |
| 1953 | 3.1 C | +0.97 C |
| 1954 | 2.1 C | -0.06 C |
| 1955 | 1.7 C | -0.46 C |
| 1957 | 1.8 C | -0.33 C |
| 1958 | 2.1 C | -0.05 C |
| 1959 | 1.3 C | -0.84 C |
| 1960 | 2.4 C | +0.18 C |
| 1961 | 3.1 C | +0.97 C |
| 1962 | 2.4 C | +0.22 C |
| 1963 | 3.3 C | +1.09 C |
| 1964 | 2.7 C | +0.54 C |
| 1965 | 1.5 C | -0.68 C |
| 1966 | 1.5 C | -0.67 C |
| 1967 | 1.7 C | -0.49 C |
| 1968 | 2.3 C | +0.11 C |
| 1969 | 2.8 C | +0.67 C |
| 1970 | 1.9 C | -0.27 C |
| 1971 | 2.3 C | +0.14 C |
| 1972 | 1.0 C | -1.16 C |
| 1973 | 3.5 C | +1.36 C |
| 1974 | 1.8 C | -0.34 C |
| 1975 | 2.6 C | +0.45 C |
| 1976 | 2.5 C | +0.33 C |
| 1977 | 3.4 C | +1.20 C |
| 1978 | 1.7 C | -0.43 C |
| 1979 | 1.0 C | -1.16 C |
| 1980 | 2.6 C | +0.46 C |
| 1983 | 3.7 C | +1.51 C |
The fitted trend in annual mean temperature here over 1923 to 1983 is 0.1 C (-0.1 to 0.2) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.1 F (-0.2 to 0.4) per decade. The slope is a straight line fitted to 55 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.1 C (-0.1 to 0.2) per decade | 0.1 F (-0.2 to 0.4) per decade | 1923 to 1983 | 55 | Not clearly different from zero |
| Mean daily maximum | -0.13 C (-0.28 to 0.02) per decade | -0.24 F (-0.51 to 0.03) per decade | 1923 to 1983 | 55 | Not clearly different from zero |
| Mean daily minimum | 0.3 C (0.1 to 0.4) per decade | 0.5 F (0.2 to 0.7) per decade | 1923 to 1983 | 55 | Rise |
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
1922 to 1983| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 40.0 C (104.0 F) | 1936 | 33.3 C (91.9 F) | 62 |
| Coldest night (TNn) | -45.6 C (-50.1 F) | 1933 | -38.9 C (-38.0 F) | 62 |
| Wettest day (Rx1day) | 73.9 mm (2.9 in) | 1973 | 35.1 mm (1.4 in) | 62 |
| Wettest five days (Rx5day) | 126.0 mm (5.0 in) | 1974 | 52.1 mm (2.1 in) | 62 |
| Longest dry spell (CDD) | 54 days | 1973 | 27 days | 62 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1922 | 30.6 C (87.1 F) |
| 1923 | 36.1 C (97.0 F) |
| 1924 | 32.8 C (91.0 F) |
| 1925 | 25.6 C (78.1 F) |
| 1926 | 34.4 C (93.9 F) |
| 1927 | 30.0 C (86.0 F) |
| 1928 | 33.3 C (91.9 F) |
| 1929 | 32.8 C (91.0 F) |
| 1930 | 33.3 C (91.9 F) |
| 1931 | 35.0 C (95.0 F) |
| 1932 | 33.3 C (91.9 F) |
| 1933 | 36.7 C (98.1 F) |
| 1934 | 32.2 C (90.0 F) |
| 1935 | 32.8 C (91.0 F) |
| 1936 | 40.0 C (104.0 F) |
| 1937 | 35.6 C (96.1 F) |
| 1938 | 33.3 C (91.9 F) |
| 1939 | 35.0 C (95.0 F) |
| 1940 | 36.7 C (98.1 F) |
| 1941 | 36.7 C (98.1 F) |
| 1942 | 31.7 C (89.1 F) |
| 1943 | 34.4 C (93.9 F) |
| 1944 | 32.2 C (90.0 F) |
| 1945 | 37.2 C (99.0 F) |
| 1946 | 33.9 C (93.0 F) |
| 1947 | 36.1 C (97.0 F) |
| 1948 | 32.2 C (90.0 F) |
| 1949 | 38.9 C (102.0 F) |
| 1950 | 32.8 C (91.0 F) |
| 1951 | 33.3 C (91.9 F) |
| 1952 | 35.0 C (95.0 F) |
| 1953 | 33.3 C (91.9 F) |
| 1954 | 31.7 C (89.1 F) |
| 1955 | 34.4 C (93.9 F) |
| 1956 | 35.6 C (96.1 F) |
| 1957 | 33.3 C (91.9 F) |
| 1958 | 35.0 C (95.0 F) |
| 1959 | 32.8 C (91.0 F) |
| 1960 | 33.9 C (93.0 F) |
| 1961 | 34.4 C (93.9 F) |
| 1962 | 33.3 C (91.9 F) |
| 1963 | 32.2 C (90.0 F) |
| 1964 | 33.9 C (93.0 F) |
| 1965 | 32.8 C (91.0 F) |
| 1966 | 32.8 C (91.0 F) |
| 1967 | 35.0 C (95.0 F) |
| 1968 | 30.6 C (87.1 F) |
| 1969 | 34.4 C (93.9 F) |
| 1970 | 33.3 C (91.9 F) |
| 1971 | 33.3 C (91.9 F) |
| 1972 | 33.3 C (91.9 F) |
| 1973 | 29.4 C (84.9 F) |
| 1974 | 33.3 C (91.9 F) |
| 1975 | 35.0 C (95.0 F) |
| 1976 | 36.7 C (98.1 F) |
| 1977 | 31.7 C (89.1 F) |
| 1978 | 32.8 C (91.0 F) |
| 1979 | 33.3 C (91.9 F) |
| 1980 | 36.0 C (96.8 F) |
| 1981 | 37.0 C (98.6 F) |
| 1982 | 31.0 C (87.8 F) |
| 1983 | 37.0 C (98.6 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1922 | -35.0 C (-31.0 F) |
| 1923 | -38.9 C (-38.0 F) |
| 1924 | -38.9 C (-38.0 F) |
| 1925 | -40.6 C (-41.1 F) |
| 1926 | -38.3 C (-36.9 F) |
| 1927 | -40.0 C (-40.0 F) |
| 1928 | -37.8 C (-36.0 F) |
| 1929 | -37.2 C (-35.0 F) |
| 1930 | -42.8 C (-45.0 F) |
| 1931 | -33.9 C (-29.0 F) |
| 1932 | -38.9 C (-38.0 F) |
| 1933 | -45.6 C (-50.1 F) |
| 1934 | -45.6 C (-50.1 F) |
| 1935 | -42.2 C (-44.0 F) |
| 1936 | -45.6 C (-50.1 F) |
| 1937 | -41.1 C (-42.0 F) |
| 1938 | -41.1 C (-42.0 F) |
| 1939 | -40.6 C (-41.1 F) |
| 1940 | -39.4 C (-38.9 F) |
| 1941 | -43.9 C (-47.0 F) |
| 1942 | -37.2 C (-35.0 F) |
| 1943 | -45.0 C (-49.0 F) |
| 1944 | -38.3 C (-36.9 F) |
| 1945 | -36.1 C (-33.0 F) |
| 1946 | -38.9 C (-38.0 F) |
| 1947 | -40.0 C (-40.0 F) |
| 1948 | -38.9 C (-38.0 F) |
| 1949 | -42.8 C (-45.0 F) |
| 1950 | -43.3 C (-45.9 F) |
| 1951 | -41.7 C (-43.1 F) |
| 1952 | -36.7 C (-34.1 F) |
| 1953 | -36.7 C (-34.1 F) |
| 1954 | -41.1 C (-42.0 F) |
| 1955 | -43.9 C (-47.0 F) |
| 1956 | -37.8 C (-36.0 F) |
| 1957 | -37.8 C (-36.0 F) |
| 1958 | -38.9 C (-38.0 F) |
| 1959 | -36.7 C (-34.1 F) |
| 1960 | -34.4 C (-29.9 F) |
| 1961 | -35.6 C (-32.1 F) |
| 1962 | -42.8 C (-45.0 F) |
| 1963 | -37.8 C (-36.0 F) |
| 1964 | -34.4 C (-29.9 F) |
| 1965 | -37.2 C (-35.0 F) |
| 1966 | -45.6 C (-50.1 F) |
| 1967 | -40.0 C (-40.0 F) |
| 1968 | -42.2 C (-44.0 F) |
| 1969 | -40.0 C (-40.0 F) |
| 1970 | -38.3 C (-36.9 F) |
| 1971 | -37.2 C (-35.0 F) |
| 1972 | -40.0 C (-40.0 F) |
| 1973 | -38.9 C (-38.0 F) |
| 1974 | -41.1 C (-42.0 F) |
| 1975 | -36.7 C (-34.1 F) |
| 1976 | -34.4 C (-29.9 F) |
| 1977 | -37.8 C (-36.0 F) |
| 1978 | -38.3 C (-36.9 F) |
| 1979 | -40.0 C (-40.0 F) |
| 1980 | -36.0 C (-32.8 F) |
| 1981 | -40.0 C (-40.0 F) |
| 1982 | -38.5 C (-37.3 F) |
| 1983 | -37.0 C (-34.6 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1922 | 31.0 mm (1.2 in) |
| 1923 | 31.2 mm (1.2 in) |
| 1924 | 29.2 mm (1.1 in) |
| 1925 | 38.1 mm (1.5 in) |
| 1926 | 48.5 mm (1.9 in) |
| 1927 | 45.5 mm (1.8 in) |
| 1928 | 17.5 mm (0.7 in) |
| 1929 | 10.2 mm (0.4 in) |
| 1930 | 15.2 mm (0.6 in) |
| 1931 | 7.6 mm (0.30 in) |
| 1932 | 10.2 mm (0.4 in) |
| 1933 | 20.3 mm (0.8 in) |
| 1934 | 6.4 mm (0.25 in) |
| 1935 | 59.4 mm (2.3 in) |
| 1936 | 35.1 mm (1.4 in) |
| 1937 | 27.7 mm (1.1 in) |
| 1938 | 36.8 mm (1.4 in) |
| 1939 | 26.9 mm (1.1 in) |
| 1940 | 23.9 mm (0.9 in) |
| 1941 | 61.5 mm (2.4 in) |
| 1942 | 50.0 mm (2.0 in) |
| 1943 | 30.2 mm (1.2 in) |
| 1944 | 55.4 mm (2.2 in) |
| 1945 | 33.8 mm (1.3 in) |
| 1946 | 35.8 mm (1.4 in) |
| 1947 | 35.1 mm (1.4 in) |
| 1948 | 20.6 mm (0.8 in) |
| 1949 | 66.3 mm (2.6 in) |
| 1950 | 36.8 mm (1.4 in) |
| 1951 | 23.1 mm (0.9 in) |
| 1952 | 30.7 mm (1.2 in) |
| 1953 | 44.7 mm (1.8 in) |
| 1954 | 33.5 mm (1.3 in) |
| 1955 | 47.2 mm (1.9 in) |
| 1956 | 24.6 mm (1.0 in) |
| 1957 | 22.9 mm (0.9 in) |
| 1958 | 42.7 mm (1.7 in) |
| 1959 | 44.5 mm (1.8 in) |
| 1960 | 26.4 mm (1.0 in) |
| 1961 | 25.4 mm (1.0 in) |
| 1962 | 38.1 mm (1.5 in) |
| 1963 | 23.9 mm (0.9 in) |
| 1964 | 36.1 mm (1.4 in) |
| 1965 | 33.3 mm (1.3 in) |
| 1966 | 23.4 mm (0.9 in) |
| 1967 | 31.5 mm (1.2 in) |
| 1968 | 35.6 mm (1.4 in) |
| 1969 | 24.4 mm (1.0 in) |
| 1970 | 54.6 mm (2.1 in) |
| 1971 | 38.9 mm (1.5 in) |
| 1972 | 26.9 mm (1.1 in) |
| 1973 | 73.9 mm (2.9 in) |
| 1974 | 49.0 mm (1.9 in) |
| 1975 | 54.6 mm (2.1 in) |
| 1976 | 32.3 mm (1.3 in) |
| 1977 | 42.2 mm (1.7 in) |
| 1978 | 44.5 mm (1.8 in) |
| 1979 | 39.1 mm (1.5 in) |
| 1980 | 46.0 mm (1.8 in) |
| 1981 | 50.7 mm (2.0 in) |
| 1982 | 50.0 mm (2.0 in) |
| 1983 | 40.0 mm (1.6 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1922 | 42.7 mm (1.7 in) |
| 1923 | 51.8 mm (2.0 in) |
| 1924 | 36.0 mm (1.4 in) |
| 1925 | 38.9 mm (1.5 in) |
| 1926 | 68.6 mm (2.7 in) |
| 1927 | 82.6 mm (3.3 in) |
| 1928 | 17.8 mm (0.7 in) |
| 1929 | 13.9 mm (0.5 in) |
| 1930 | 29.2 mm (1.1 in) |
| 1931 | 9.7 mm (0.38 in) |
| 1932 | 16.6 mm (0.7 in) |
| 1933 | 21.6 mm (0.9 in) |
| 1934 | 15.8 mm (0.6 in) |
| 1935 | 83.6 mm (3.3 in) |
| 1936 | 42.7 mm (1.7 in) |
| 1937 | 34.1 mm (1.3 in) |
| 1938 | 42.6 mm (1.7 in) |
| 1939 | 75.7 mm (3.0 in) |
| 1940 | 30.4 mm (1.2 in) |
| 1941 | 124.5 mm (4.9 in) |
| 1942 | 65.5 mm (2.6 in) |
| 1943 | 47.7 mm (1.9 in) |
| 1944 | 81.8 mm (3.2 in) |
| 1945 | 59.1 mm (2.3 in) |
| 1946 | 52.4 mm (2.1 in) |
| 1947 | 73.8 mm (2.9 in) |
| 1948 | 49.0 mm (1.9 in) |
| 1949 | 71.4 mm (2.8 in) |
| 1950 | 68.2 mm (2.7 in) |
| 1951 | 33.3 mm (1.3 in) |
| 1952 | 31.7 mm (1.2 in) |
| 1953 | 54.1 mm (2.1 in) |
| 1954 | 40.6 mm (1.6 in) |
| 1955 | 82.7 mm (3.3 in) |
| 1956 | 65.8 mm (2.6 in) |
| 1957 | 29.0 mm (1.1 in) |
| 1958 | 57.9 mm (2.3 in) |
| 1959 | 65.5 mm (2.6 in) |
| 1960 | 46.8 mm (1.8 in) |
| 1961 | 39.4 mm (1.6 in) |
| 1962 | 58.9 mm (2.3 in) |
| 1963 | 40.5 mm (1.6 in) |
| 1964 | 53.6 mm (2.1 in) |
| 1965 | 61.0 mm (2.4 in) |
| 1966 | 43.2 mm (1.7 in) |
| 1967 | 39.6 mm (1.6 in) |
| 1968 | 58.6 mm (2.3 in) |
| 1969 | 37.3 mm (1.5 in) |
| 1970 | 65.5 mm (2.6 in) |
| 1971 | 51.3 mm (2.0 in) |
| 1972 | 39.6 mm (1.6 in) |
| 1973 | 82.7 mm (3.3 in) |
| 1974 | 126.0 mm (5.0 in) |
| 1975 | 80.3 mm (3.2 in) |
| 1976 | 59.9 mm (2.4 in) |
| 1977 | 49.3 mm (1.9 in) |
| 1978 | 66.6 mm (2.6 in) |
| 1979 | 61.7 mm (2.4 in) |
| 1980 | 47.6 mm (1.9 in) |
| 1981 | 68.4 mm (2.7 in) |
| 1982 | 62.4 mm (2.5 in) |
| 1983 | 78.6 mm (3.1 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1922 | 20 days |
| 1923 | 23 days |
| 1924 | 20 days |
| 1925 | 24 days |
| 1926 | 39 days |
| 1927 | 36 days |
| 1928 | 48 days |
| 1929 | 17 days |
| 1930 | 23 days |
| 1931 | 27 days |
| 1932 | 49 days |
| 1933 | 15 days |
| 1934 | 28 days |
| 1935 | 29 days |
| 1936 | 20 days |
| 1937 | 14 days |
| 1938 | 24 days |
| 1939 | 42 days |
| 1940 | 30 days |
| 1941 | 20 days |
| 1942 | 20 days |
| 1943 | 23 days |
| 1944 | 41 days |
| 1945 | 23 days |
| 1946 | 18 days |
| 1947 | 16 days |
| 1948 | 31 days |
| 1949 | 20 days |
| 1950 | 13 days |
| 1951 | 18 days |
| 1952 | 19 days |
| 1953 | 25 days |
| 1954 | 24 days |
| 1955 | 36 days |
| 1956 | 32 days |
| 1957 | 32 days |
| 1958 | 26 days |
| 1959 | 21 days |
| 1960 | 37 days |
| 1961 | 25 days |
| 1962 | 26 days |
| 1963 | 27 days |
| 1964 | 23 days |
| 1965 | 27 days |
| 1966 | 26 days |
| 1967 | 27 days |
| 1968 | 41 days |
| 1969 | 48 days |
| 1970 | 40 days |
| 1971 | 15 days |
| 1972 | 23 days |
| 1973 | 54 days |
| 1974 | 24 days |
| 1975 | 30 days |
| 1976 | 53 days |
| 1977 | 28 days |
| 1978 | 41 days |
| 1979 | 27 days |
| 1980 | 33 days |
| 1981 | 48 days |
| 1982 | 32 days |
| 1983 | 39 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
55 years with a frostAcross 55 years with a frost, the median last spring frost at Great Falls falls on 18 May and the median first autumn frost on 25 September, which leaves a median of 130 days between them.
Fitted over all years, the growing season changes by +0.3 days per decade at this station.
| Measure | Median, all years | Earliest period | Recent period (1951 to 1983) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 18 May | n/a | 17 May | n/a | -1.0 days per decade |
| First autumn frost | 25 September | n/a | 24 September | n/a | -0.7 days per decade |
| Growing days | 130 days | n/a | 128 days | n/a | +0.3 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
50 years, 1925 to 1983A day with at least 36.4 mm (1.4 in) of rain is expected about once in 2 years. A day with at least 75.8 mm (3.0 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 36.4 mm (1.4 in) | |
| 5 years | 47.5 mm (1.9 in) | |
| 10 years | 54.6 mm (2.1 in) | |
| 25 years | 63.3 mm (2.5 in) | |
| 50 years | 69.6 mm (2.7 in) | |
| 100 years | 75.8 mm (3.0 in) | Longer than the 50 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, 50 years of values from 1925 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: 73.9 mm (2.9 in) in 1973; 66.3 mm (2.6 in) in 1949; 61.5 mm (2.4 in) in 1941.
Station Changes
2 suspected2 changes were suspected in the annual mean temperature of Great Falls, at 1930 and 1960. Each is measured against neighbouring stations.
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1930 ran 0.7 C (1.3 F) lower than in the years before (likely change).
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1960 ran 0.4 C (0.7 F) higher than in the years before (likely change).
| Year | Shift (C) | Shift (F) | Strength | Neighbours |
|---|---|---|---|---|
| 1930 | -0.7 | -1.3 | likely | 5 |
| 1960 | +0.4 | +0.7 | 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 2026-10-17 (17 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-17).