Great Falls Weather Records (USC00183850)
Record envelope, standing records and threshold days for Great Falls (USC00183850), Maryland, United States, with 58 years of record.
Key Facts for Great Falls
- Great Falls (USC00183850) is a weather station in Maryland, United States at 39.00 latitude and -77.25 longitude, 61 m (200 ft) above sea level.
- The station reports from 1893 to 1950, 58 years of record.
- 1,464 records set at Great Falls still stand.
- Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
- Great Falls set a daily record low maximum temperature of 15.0 C (59.0 F) on 25 September 1950.
About the Station
- Location: Maryland, United States, 39.00 latitude, -77.25 longitude.
- Elevation: 61 m (200 ft).
- Period of record: 1893 to 1950, 58 years.
- Eligible elements: tmax, tmin, prcp.
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 | 26.7 C (80.1 F) | -29.4 C (-20.9 F) | n/a | n/a |
| Feb | 27.8 C (82.0 F) | -25.6 C (-14.1 F) | n/a | n/a |
| Mar | 32.8 C (91.0 F) | -15.0 C (5.0 F) | n/a | n/a |
| Apr | 36.1 C (97.0 F) | -10.0 C (14.0 F) | n/a | n/a |
| May | 37.2 C (99.0 F) | -2.2 C (28.0 F) | n/a | n/a |
| Jun | 39.4 C (102.9 F) | 3.3 C (37.9 F) | n/a | n/a |
| Jul | 41.1 C (106.0 F) | 7.2 C (45.0 F) | n/a | n/a |
| Aug | 40.6 C (105.1 F) | 3.3 C (37.9 F) | n/a | n/a |
| Sep | 38.3 C (100.9 F) | 0.6 C (33.1 F) | n/a | n/a |
| Oct | 36.7 C (98.1 F) | -6.1 C (21.0 F) | n/a | n/a |
| Nov | 27.8 C (82.0 F) | -16.7 C (1.9 F) | n/a | n/a |
| Dec | 23.9 C (75.0 F) | -24.4 C (-11.9 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1897 | 5 |
| 1898 | 24 |
| 1899 | 26 |
| 1900 | 49 |
| 1901 | 41 |
| 1902 | 27 |
| 1903 | 29 |
| 1904 | 31 |
| 1905 | 27 |
| 1906 | 25 |
| 1907 | 27 |
| 1908 | 25 |
| 1909 | 27 |
| 1910 | 29 |
| 1911 | 18 |
| 1912 | 27 |
| 1913 | 18 |
| 1914 | 39 |
| 1915 | 22 |
| 1916 | 28 |
| 1917 | 40 |
| 1918 | 25 |
| 1919 | 9 |
| 1920 | 17 |
| 1921 | 30 |
| 1922 | 15 |
| 1923 | 30 |
| 1924 | 17 |
| 1925 | 33 |
| 1926 | 31 |
| 1927 | 35 |
| 1928 | 26 |
| 1929 | 38 |
| 1930 | 71 |
| 1931 | 29 |
| 1932 | 35 |
| 1933 | 23 |
| 1934 | 25 |
| 1935 | 30 |
| 1936 | 31 |
| 1937 | 23 |
| 1938 | 33 |
| 1939 | 26 |
| 1940 | 30 |
| 1941 | 26 |
| 1942 | 23 |
| 1943 | 24 |
| 1944 | 9 |
| 1945 | 25 |
| 1946 | 22 |
| 1947 | 21 |
| 1948 | 25 |
| 1949 | 19 |
| 1950 | 24 |
All-Time Record Progression
4 new records| Date | Kind | Detail |
|---|---|---|
| 1924-09-30 | Record daily precipitation | Record daily precipitation 104.1 mm (4.1 in) |
| 1930-07-20 | Record high maximum temperature | Record high maximum temperature 40.6 C (105.1 F) |
| 1933-08-24 | Record daily precipitation | Record daily precipitation 159.0 mm (6.3 in) |
| 1936-07-10 | Record high maximum temperature | Record high maximum temperature 41.1 C (106.0 F) |
Wettest Day of Each Month
Aug: 159.0 mm (6.3 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 57.2 mm (2.3 in) | 13 January 1915 |
| Feb | 52.1 mm (2.1 in) | 14 February 1936 |
| Mar | 51.8 mm (2.0 in) | 23 March 1903 |
| Apr | 56.9 mm (2.2 in) | 9 April 1940 |
| May | 66.0 mm (2.6 in) | 20 May 1908 |
| Jun | 58.9 mm (2.3 in) | 30 June 1904 |
| Jul | 77.2 mm (3.0 in) | 6 July 1945 |
| Aug | 159.0 mm (6.3 in) | 24 August 1933 |
| Sep | 104.1 mm (4.1 in) | 30 September 1924 |
| Oct | 91.4 mm (3.6 in) | 20 October 1906 |
| Nov | 75.7 mm (3.0 in) | 9 November 1943 |
| Dec | 63.5 mm (2.5 in) | 29 December 1901 |
Period of Record Coverage
1897 to 1950| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1897 | 112 | 31% | No |
| 1898 | 283 | 78% | No |
| 1899 | 330 | 90% | Yes |
| 1900 | 364 | 100% | Yes |
| 1901 | 352 | 96% | Yes |
| 1902 | 364 | 100% | Yes |
| 1903 | 354 | 97% | Yes |
| 1904 | 364 | 99% | Yes |
| 1905 | 364 | 100% | Yes |
| 1906 | 318 | 87% | No |
| 1907 | 362 | 99% | Yes |
| 1908 | 363 | 99% | Yes |
| 1909 | 363 | 99% | Yes |
| 1910 | 365 | 100% | Yes |
| 1911 | 294 | 81% | No |
| 1912 | 365 | 100% | Yes |
| 1913 | 335 | 92% | Yes |
| 1914 | 365 | 100% | Yes |
| 1915 | 364 | 100% | Yes |
| 1916 | 325 | 89% | No |
| 1917 | 365 | 100% | Yes |
| 1918 | 210 | 58% | No |
| 1919 | 72 | 20% | No |
| 1920 | 362 | 99% | Yes |
| 1921 | 361 | 99% | Yes |
| 1922 | 365 | 100% | Yes |
| 1923 | 364 | 100% | Yes |
| 1924 | 364 | 99% | Yes |
| 1925 | 365 | 100% | Yes |
| 1926 | 365 | 100% | Yes |
| 1927 | 365 | 100% | Yes |
| 1928 | 365 | 100% | Yes |
| 1929 | 364 | 100% | Yes |
| 1930 | 359 | 98% | Yes |
| 1931 | 365 | 100% | Yes |
| 1932 | 366 | 100% | Yes |
| 1933 | 364 | 100% | Yes |
| 1934 | 272 | 75% | No |
| 1935 | 365 | 100% | Yes |
| 1936 | 365 | 100% | Yes |
| 1937 | 365 | 100% | Yes |
| 1938 | 334 | 92% | Yes |
| 1939 | 365 | 100% | Yes |
| 1940 | 366 | 100% | Yes |
| 1941 | 365 | 100% | Yes |
| 1942 | 364 | 100% | Yes |
| 1943 | 365 | 100% | Yes |
| 1944 | 335 | 92% | Yes |
| 1945 | 365 | 100% | Yes |
| 1946 | 364 | 100% | Yes |
| 1947 | 334 | 92% | Yes |
| 1948 | 360 | 98% | Yes |
| 1949 | 364 | 100% | Yes |
| 1950 | 272 | 75% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 25 September 1950 | Great Falls, US | daily low max | 15.0 C (59.0 F) | 1.1 C (2.0 F) | 21 years | 13 of 100 (Routine) |
| 13 September 1950 | Great Falls, US | daily low max (Tie) | 18.3 C (64.9 F) | tie | 11 years | 2 of 100 (Routine) |
| 1 September 1950 | Great Falls, US | daily high min | 21.7 C (71.1 F) | 0.6 C (1.1 F) | 51 years | 21 of 100 (Routine) |
| 23 July 1950 | Great Falls, US | daily low max | 24.4 C (75.9 F) | 1.7 C (3.1 F) | 12 years | 13 of 100 (Routine) |
| 29 June 1950 | Great Falls, US | daily rain | 44.7 mm (1.8 in) | 5.8 mm (0.23 in) | 36 years | 20 of 100 (Routine) |
| 11 June 1950 | Great Falls, US | daily rain | 31.2 mm (1.2 in) | 6.3 mm (0.25 in) | 44 years | 24 of 100 (Routine) |
| 19 May 1950 | Great Falls, US | daily low max | 16.1 C (61.0 F) | 1.7 C (3.1 F) | 50 years | 23 of 100 (Routine) |
| 6 May 1950 | Great Falls, US | daily high min | 18.9 C (66.0 F) | 0.6 C (1.1 F) | 0 years | 6 of 100 (Routine) |
| 14 April 1950 | Great Falls, US | daily low min | -5.6 C (21.9 F) | 2.3 C (4.1 F) | 9 years | 11 of 100 (Routine) |
| 9 April 1950 | Great Falls, US | daily low min (Tie) | -2.8 C (27.0 F) | tie | 32 years | 3 of 100 (Routine) |
| 8 April 1950 | Great Falls, US | daily low min | -3.3 C (26.1 F) | 0.5 C (0.9 F) | 32 years | 15 of 100 (Routine) |
| 4 April 1950 | Great Falls, US | daily high min | 16.7 C (62.1 F) | 3.4 C (6.1 F) | 27 years | 20 of 100 (Routine) |
| 4 April 1950 | Great Falls, US | daily high max | 28.3 C (82.9 F) | 1.1 C (2.0 F) | 28 years | 14 of 100 (Routine) |
| 28 March 1950 | Great Falls, US | daily high min | 15.6 C (60.1 F) | 0.6 C (1.1 F) | 41 years | 18 of 100 (Routine) |
| 22 March 1950 | Great Falls, US | daily rain | 44.2 mm (1.7 in) | 15.8 mm (0.6 in) | 32 years | 33 of 100 (Routine) |
| 12 March 1950 | Great Falls, US | daily rain | 24.6 mm (1.0 in) | 0.2 mm (0.01 in) | 13 years | 9 of 100 (Routine) |
| 3 March 1950 | Great Falls, US | daily low min | -13.9 C (7.0 F) | 1.7 C (3.1 F) | 44 years | 21 of 100 (Routine) |
| 31 January 1950 | Great Falls, US | daily rain (Tie) | 20.3 mm (0.8 in) | tie | 7 years | 1 of 100 (Routine) |
| 29 January 1950 | Great Falls, US | daily high min (Tie) | 1.7 C (35.1 F) | tie | 34 years | 3 of 100 (Routine) |
| 27 January 1950 | Great Falls, US | daily high max | 25.0 C (77.0 F) | 1.7 C (3.1 F) | 6 years | 8 of 100 (Routine) |
Climate Trend
38 complete years, 1900 to 1949| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1900 | 12.5 C | +0.00 C |
| 1902 | 12.1 C | -0.43 C |
| 1903 | 11.7 C | -0.86 C |
| 1904 | 10.9 C | -1.61 C |
| 1905 | 12.0 C | -0.50 C |
| 1907 | 11.4 C | -1.14 C |
| 1908 | 12.6 C | +0.04 C |
| 1909 | 12.1 C | -0.41 C |
| 1910 | 12.2 C | -0.34 C |
| 1912 | 12.0 C | -0.49 C |
| 1915 | 12.6 C | +0.02 C |
| 1917 | 11.0 C | -1.53 C |
| 1920 | 11.9 C | -0.66 C |
| 1921 | 13.8 C | +1.25 C |
| 1922 | 13.0 C | +0.50 C |
| 1923 | 12.7 C | +0.21 C |
| 1924 | 11.6 C | -0.91 C |
| 1925 | 12.6 C | +0.06 C |
| 1926 | 11.8 C | -0.74 C |
| 1927 | 12.7 C | +0.17 C |
| 1928 | 12.4 C | -0.11 C |
| 1929 | 12.6 C | +0.06 C |
| 1930 | 12.9 C | +0.35 C |
| 1931 | 13.5 C | +0.92 C |
| 1932 | 12.9 C | +0.34 C |
| 1933 | 12.9 C | +0.39 C |
| 1935 | 12.2 C | -0.34 C |
| 1936 | 12.5 C | -0.05 C |
| 1937 | 12.8 C | +0.27 C |
| 1939 | 13.5 C | +0.95 C |
| 1940 | 11.9 C | -0.66 C |
| 1941 | 13.2 C | +0.67 C |
| 1942 | 13.3 C | +0.72 C |
| 1943 | 13.0 C | +0.42 C |
| 1945 | 13.1 C | +0.59 C |
| 1946 | 13.6 C | +1.11 C |
| 1948 | 12.9 C | +0.36 C |
| 1949 | 13.7 C | +1.21 C |
The annual mean temperature here has risen by 0.3 C (0.2 to 0.4) per decade over 1900 to 1949. In Fahrenheit: 0.6 F (0.3 to 0.8) per decade. The slope is a straight line fitted to 38 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.3 C (0.2 to 0.4) per decade | 0.6 F (0.3 to 0.8) per decade | 1900 to 1949 | 38 | Rise |
| Mean daily maximum | 0.4 C (0.3 to 0.6) per decade | 0.7 F (0.5 to 1.0) per decade | 1900 to 1949 | 38 | Rise |
| Mean daily minimum | 0.2 C (0.1 to 0.3) per decade | 0.4 F (0.1 to 0.6) per decade | 1900 to 1949 | 38 | 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
1893 to 1950| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 41.1 C (106.0 F) | 1936 | 36.7 C (98.1 F) | 54 |
| Coldest night (TNn) | -29.4 C (-20.9 F) | 1912 | -16.7 C (1.9 F) | 54 |
| Wettest day (Rx1day) | 159.0 mm (6.3 in) | 1933 | 57.7 mm (2.3 in) | 58 |
| Wettest five days (Rx5day) | 217.7 mm (8.6 in) | 1937 | 89.7 mm (3.5 in) | 58 |
| Longest dry spell (CDD) | 40 days | 1901 | 19 days | 58 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1893 | n/a |
| 1894 | n/a |
| 1895 | n/a |
| 1896 | n/a |
| 1897 | 35.0 C (95.0 F) |
| 1898 | 37.8 C (100.0 F) |
| 1899 | 35.6 C (96.1 F) |
| 1900 | 37.2 C (99.0 F) |
| 1901 | 36.1 C (97.0 F) |
| 1902 | 40.0 C (104.0 F) |
| 1903 | 37.8 C (100.0 F) |
| 1904 | 35.6 C (96.1 F) |
| 1905 | 36.7 C (98.1 F) |
| 1906 | 36.1 C (97.0 F) |
| 1907 | 35.6 C (96.1 F) |
| 1908 | 37.8 C (100.0 F) |
| 1909 | 37.2 C (99.0 F) |
| 1910 | 35.6 C (96.1 F) |
| 1911 | 37.2 C (99.0 F) |
| 1912 | 35.6 C (96.1 F) |
| 1913 | 37.2 C (99.0 F) |
| 1914 | 37.2 C (99.0 F) |
| 1915 | 36.7 C (98.1 F) |
| 1916 | 36.1 C (97.0 F) |
| 1917 | 37.8 C (100.0 F) |
| 1918 | 34.4 C (93.9 F) |
| 1919 | 28.9 C (84.0 F) |
| 1920 | 35.6 C (96.1 F) |
| 1921 | 36.1 C (97.0 F) |
| 1922 | 36.1 C (97.0 F) |
| 1923 | 36.7 C (98.1 F) |
| 1924 | 38.3 C (100.9 F) |
| 1925 | 38.3 C (100.9 F) |
| 1926 | 40.0 C (104.0 F) |
| 1927 | 35.6 C (96.1 F) |
| 1928 | 35.6 C (96.1 F) |
| 1929 | 36.7 C (98.1 F) |
| 1930 | 40.6 C (105.1 F) |
| 1931 | 37.8 C (100.0 F) |
| 1932 | 37.8 C (100.0 F) |
| 1933 | 37.2 C (99.0 F) |
| 1934 | 39.4 C (102.9 F) |
| 1935 | 36.1 C (97.0 F) |
| 1936 | 41.1 C (106.0 F) |
| 1937 | 35.6 C (96.1 F) |
| 1938 | 37.8 C (100.0 F) |
| 1939 | 37.8 C (100.0 F) |
| 1940 | 38.9 C (102.0 F) |
| 1941 | 37.8 C (100.0 F) |
| 1942 | 36.7 C (98.1 F) |
| 1943 | 38.3 C (100.9 F) |
| 1944 | 36.7 C (98.1 F) |
| 1945 | 38.3 C (100.9 F) |
| 1946 | 35.0 C (95.0 F) |
| 1947 | 36.1 C (97.0 F) |
| 1948 | 37.2 C (99.0 F) |
| 1949 | 36.1 C (97.0 F) |
| 1950 | 35.0 C (95.0 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1893 | n/a |
| 1894 | n/a |
| 1895 | n/a |
| 1896 | n/a |
| 1897 | -12.2 C (10.0 F) |
| 1898 | -16.1 C (3.0 F) |
| 1899 | -25.6 C (-14.1 F) |
| 1900 | -18.9 C (-2.0 F) |
| 1901 | -16.7 C (1.9 F) |
| 1902 | -17.2 C (1.0 F) |
| 1903 | -21.7 C (-7.1 F) |
| 1904 | -20.0 C (-4.0 F) |
| 1905 | -20.6 C (-5.1 F) |
| 1906 | -12.2 C (10.0 F) |
| 1907 | -21.1 C (-6.0 F) |
| 1908 | -16.1 C (3.0 F) |
| 1909 | -14.4 C (6.1 F) |
| 1910 | -16.7 C (1.9 F) |
| 1911 | -13.9 C (7.0 F) |
| 1912 | -29.4 C (-20.9 F) |
| 1913 | -12.2 C (10.0 F) |
| 1914 | -21.7 C (-7.1 F) |
| 1915 | -11.1 C (12.0 F) |
| 1916 | -19.4 C (-2.9 F) |
| 1917 | -24.4 C (-11.9 F) |
| 1918 | -24.4 C (-11.9 F) |
| 1919 | -19.4 C (-2.9 F) |
| 1920 | -15.0 C (5.0 F) |
| 1921 | -14.4 C (6.1 F) |
| 1922 | -16.7 C (1.9 F) |
| 1923 | -12.2 C (10.0 F) |
| 1924 | -15.0 C (5.0 F) |
| 1925 | -19.4 C (-2.9 F) |
| 1926 | -17.8 C (0.0 F) |
| 1927 | -14.4 C (6.1 F) |
| 1928 | -20.0 C (-4.0 F) |
| 1929 | -15.0 C (5.0 F) |
| 1930 | -22.2 C (-8.0 F) |
| 1931 | -13.9 C (7.0 F) |
| 1932 | -16.7 C (1.9 F) |
| 1933 | -16.7 C (1.9 F) |
| 1934 | -23.9 C (-11.0 F) |
| 1935 | -26.1 C (-15.0 F) |
| 1936 | -23.3 C (-9.9 F) |
| 1937 | -12.2 C (10.0 F) |
| 1938 | -15.0 C (5.0 F) |
| 1939 | -12.8 C (9.0 F) |
| 1940 | -20.6 C (-5.1 F) |
| 1941 | -11.7 C (10.9 F) |
| 1942 | -22.2 C (-8.0 F) |
| 1943 | -17.8 C (0.0 F) |
| 1944 | -12.2 C (10.0 F) |
| 1945 | -16.1 C (3.0 F) |
| 1946 | -17.8 C (0.0 F) |
| 1947 | -17.2 C (1.0 F) |
| 1948 | -16.1 C (3.0 F) |
| 1949 | -11.1 C (12.0 F) |
| 1950 | -13.9 C (7.0 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1893 | 66.0 mm (2.6 in) |
| 1894 | 49.0 mm (1.9 in) |
| 1895 | 50.8 mm (2.0 in) |
| 1896 | 40.6 mm (1.6 in) |
| 1897 | 47.0 mm (1.9 in) |
| 1898 | 48.3 mm (1.9 in) |
| 1899 | 56.1 mm (2.2 in) |
| 1900 | 35.6 mm (1.4 in) |
| 1901 | 63.5 mm (2.5 in) |
| 1902 | 70.6 mm (2.8 in) |
| 1903 | 51.8 mm (2.0 in) |
| 1904 | 58.9 mm (2.3 in) |
| 1905 | 63.0 mm (2.5 in) |
| 1906 | 91.4 mm (3.6 in) |
| 1907 | 71.9 mm (2.8 in) |
| 1908 | 90.2 mm (3.6 in) |
| 1909 | 48.8 mm (1.9 in) |
| 1910 | 48.3 mm (1.9 in) |
| 1911 | 40.6 mm (1.6 in) |
| 1912 | 62.2 mm (2.4 in) |
| 1913 | 48.8 mm (1.9 in) |
| 1914 | 45.7 mm (1.8 in) |
| 1915 | 65.5 mm (2.6 in) |
| 1916 | 63.8 mm (2.5 in) |
| 1917 | 64.8 mm (2.6 in) |
| 1918 | 44.5 mm (1.8 in) |
| 1919 | 34.5 mm (1.4 in) |
| 1920 | 65.8 mm (2.6 in) |
| 1921 | 44.5 mm (1.8 in) |
| 1922 | 82.6 mm (3.3 in) |
| 1923 | 76.2 mm (3.0 in) |
| 1924 | 104.1 mm (4.1 in) |
| 1925 | 50.3 mm (2.0 in) |
| 1926 | 71.9 mm (2.8 in) |
| 1927 | 54.4 mm (2.1 in) |
| 1928 | 60.5 mm (2.4 in) |
| 1929 | 76.2 mm (3.0 in) |
| 1930 | 56.6 mm (2.2 in) |
| 1931 | 43.2 mm (1.7 in) |
| 1932 | 65.5 mm (2.6 in) |
| 1933 | 159.0 mm (6.3 in) |
| 1934 | 48.5 mm (1.9 in) |
| 1935 | 72.4 mm (2.9 in) |
| 1936 | 73.7 mm (2.9 in) |
| 1937 | 93.7 mm (3.7 in) |
| 1938 | 45.7 mm (1.8 in) |
| 1939 | 58.4 mm (2.3 in) |
| 1940 | 56.9 mm (2.2 in) |
| 1941 | 45.5 mm (1.8 in) |
| 1942 | 86.4 mm (3.4 in) |
| 1943 | 75.7 mm (3.0 in) |
| 1944 | 83.8 mm (3.3 in) |
| 1945 | 77.2 mm (3.0 in) |
| 1946 | 52.6 mm (2.1 in) |
| 1947 | 44.5 mm (1.8 in) |
| 1948 | 54.6 mm (2.1 in) |
| 1949 | 52.8 mm (2.1 in) |
| 1950 | 44.7 mm (1.8 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1893 | 71.1 mm (2.8 in) |
| 1894 | 70.4 mm (2.8 in) |
| 1895 | 87.1 mm (3.4 in) |
| 1896 | 77.6 mm (3.1 in) |
| 1897 | 73.5 mm (2.9 in) |
| 1898 | 90.9 mm (3.6 in) |
| 1899 | 67.3 mm (2.6 in) |
| 1900 | 60.4 mm (2.4 in) |
| 1901 | 119.6 mm (4.7 in) |
| 1902 | 140.0 mm (5.5 in) |
| 1903 | 94.4 mm (3.7 in) |
| 1904 | 121.4 mm (4.8 in) |
| 1905 | 104.9 mm (4.1 in) |
| 1906 | 150.9 mm (5.9 in) |
| 1907 | 102.4 mm (4.0 in) |
| 1908 | 113.7 mm (4.5 in) |
| 1909 | 65.0 mm (2.6 in) |
| 1910 | 82.1 mm (3.2 in) |
| 1911 | 106.6 mm (4.2 in) |
| 1912 | 92.4 mm (3.6 in) |
| 1913 | 84.6 mm (3.3 in) |
| 1914 | 96.8 mm (3.8 in) |
| 1915 | 84.2 mm (3.3 in) |
| 1916 | 166.1 mm (6.5 in) |
| 1917 | 83.9 mm (3.3 in) |
| 1918 | 80.9 mm (3.2 in) |
| 1919 | 66.8 mm (2.6 in) |
| 1920 | 65.8 mm (2.6 in) |
| 1921 | 83.3 mm (3.3 in) |
| 1922 | 107.5 mm (4.2 in) |
| 1923 | 103.9 mm (4.1 in) |
| 1924 | 130.0 mm (5.1 in) |
| 1925 | 98.8 mm (3.9 in) |
| 1926 | 88.4 mm (3.5 in) |
| 1927 | 66.5 mm (2.6 in) |
| 1928 | 110.0 mm (4.3 in) |
| 1929 | 114.8 mm (4.5 in) |
| 1930 | 66.2 mm (2.6 in) |
| 1931 | 51.0 mm (2.0 in) |
| 1932 | 110.7 mm (4.4 in) |
| 1933 | 205.0 mm (8.1 in) |
| 1934 | 70.6 mm (2.8 in) |
| 1935 | 155.8 mm (6.1 in) |
| 1936 | 114.4 mm (4.5 in) |
| 1937 | 217.7 mm (8.6 in) |
| 1938 | 62.2 mm (2.4 in) |
| 1939 | 82.2 mm (3.2 in) |
| 1940 | 73.7 mm (2.9 in) |
| 1941 | 61.7 mm (2.4 in) |
| 1942 | 179.9 mm (7.1 in) |
| 1943 | 81.0 mm (3.2 in) |
| 1944 | 93.5 mm (3.7 in) |
| 1945 | 126.2 mm (5.0 in) |
| 1946 | 81.6 mm (3.2 in) |
| 1947 | 67.1 mm (2.6 in) |
| 1948 | 100.8 mm (4.0 in) |
| 1949 | 120.1 mm (4.7 in) |
| 1950 | 60.3 mm (2.4 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1893 | 21 days |
| 1894 | 24 days |
| 1895 | 24 days |
| 1896 | 19 days |
| 1897 | 14 days |
| 1898 | 34 days |
| 1899 | 21 days |
| 1900 | 15 days |
| 1901 | 40 days |
| 1902 | 20 days |
| 1903 | 37 days |
| 1904 | 20 days |
| 1905 | 24 days |
| 1906 | 17 days |
| 1907 | 19 days |
| 1908 | 21 days |
| 1909 | 39 days |
| 1910 | 24 days |
| 1911 | 15 days |
| 1912 | 23 days |
| 1913 | 15 days |
| 1914 | 27 days |
| 1915 | 23 days |
| 1916 | 13 days |
| 1917 | 22 days |
| 1918 | 9 days |
| 1919 | 10 days |
| 1920 | 21 days |
| 1921 | 16 days |
| 1922 | 25 days |
| 1923 | 25 days |
| 1924 | 26 days |
| 1925 | 13 days |
| 1926 | 16 days |
| 1927 | 14 days |
| 1928 | 17 days |
| 1929 | 15 days |
| 1930 | 26 days |
| 1931 | 28 days |
| 1932 | 15 days |
| 1933 | 11 days |
| 1934 | 15 days |
| 1935 | 11 days |
| 1936 | 22 days |
| 1937 | 20 days |
| 1938 | 13 days |
| 1939 | 18 days |
| 1940 | 14 days |
| 1941 | 19 days |
| 1942 | 18 days |
| 1943 | 18 days |
| 1944 | 19 days |
| 1945 | 15 days |
| 1946 | 21 days |
| 1947 | 33 days |
| 1948 | 12 days |
| 1949 | 26 days |
| 1950 | 13 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
38 years with a frostAcross 38 years with a frost, the median last spring frost at Great Falls falls on 25 April and the median first autumn frost on 19 October, which leaves a median of 179 days between them.
Fitted over all years, the growing season changes by +0.4 days per decade at this station.
| Measure | Median, all years | Earliest period | Recent period (1910 to 1949) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 25 April | n/a | 26 April | n/a | +1.2 days per decade |
| First autumn frost | 19 October | n/a | 21 October | n/a | +1.6 days per decade |
| Growing days | 179 days | n/a | 180 days | n/a | +0.4 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, 1894 to 1949A day with at least 58.8 mm (2.3 in) of rain is expected about once in 2 years. A day with at least 131.4 mm (5.2 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 58.8 mm (2.3 in) | |
| 5 years | 75.0 mm (3.0 in) | |
| 10 years | 86.9 mm (3.4 in) | |
| 25 years | 103.5 mm (4.1 in) | |
| 50 years | 117.0 mm (4.6 in) | Longer than the 46 years of record |
| 100 years | 131.4 mm (5.2 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 1894 to 1949.
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: 159.0 mm (6.3 in) in 1933; 93.7 mm (3.7 in) in 1937; 90.2 mm (3.6 in) in 1908.
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 (2025-12-31).