Dillon AP Weather Records (USW00024138)
Record envelope, standing records and threshold days for Dillon AP (USW00024138), Montana, United States, with 87 years of record.
Key Facts for Dillon AP
- Dillon AP (USW00024138) is a weather station in Montana, United States at 45.26 latitude and -112.55 longitude, 1,585 m (5,199 ft) above sea level.
- The station reports from 1940 to 2026, 87 years of record.
- 1,464 records set at Dillon AP still stand.
- Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
- Dillon AP set a daily record high minimum temperature of 10.0 C (50.0 F) on 5 October 2026 (provisional).
Provisional Records
Records set in the last 60 days are provisional until they clear the revision window.
About the Station
- Location: Montana, United States, 45.26 latitude, -112.55 longitude.
- Elevation: 1,585 m (5,199 ft).
- Period of record: 1940 to 2026, 87 years.
- Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
24 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 14.4 C (57.9 F) | -40.5 C (-40.9 F) | 13.9 C (57.0 F) | -18.9 C (-2.0 F) |
| Feb | 17.8 C (64.0 F) | -36.7 C (-34.1 F) | 16.1 C (61.0 F) | -18.9 C (-2.0 F) |
| Mar | 26.1 C (79.0 F) | -30.5 C (-22.9 F) | 24.4 C (75.9 F) | -15.0 C (5.0 F) |
| Apr | 29.4 C (84.9 F) | -20.6 C (-5.1 F) | 24.4 C (75.9 F) | -7.2 C (19.0 F) |
| May | 32.2 C (90.0 F) | -10.0 C (14.0 F) | 30.6 C (87.1 F) | -5.0 C (23.0 F) |
| Jun | 36.7 C (98.1 F) | -3.9 C (25.0 F) | 28.3 C (82.9 F) | 1.7 C (35.1 F) |
| Jul | 38.9 C (102.0 F) | 0.0 C (32.0 F) | 37.2 C (99.0 F) | 6.7 C (44.1 F) |
| Aug | 38.9 C (102.0 F) | -1.1 C (30.0 F) | 33.9 C (93.0 F) | 3.3 C (37.9 F) |
| Sep | 36.1 C (97.0 F) | -12.2 C (10.0 F) | 28.3 C (82.9 F) | -0.6 C (30.9 F) |
| Oct | 30.0 C (86.0 F) | -22.7 C (-8.9 F) | 28.9 C (84.0 F) | -7.2 C (19.0 F) |
| Nov | 21.7 C (71.1 F) | -33.9 C (-29.0 F) | n/a | n/a |
| Dec | 16.7 C (62.1 F) | -38.3 C (-36.9 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1940 | 14 |
| 1941 | 12 |
| 1942 | 11 |
| 1943 | 22 |
| 1944 | 10 |
| 1945 | 19 |
| 1946 | 9 |
| 1947 | 12 |
| 1948 | 16 |
| 1949 | 31 |
| 1950 | 36 |
| 1951 | 25 |
| 1952 | 12 |
| 1953 | 17 |
| 1954 | 25 |
| 1955 | 30 |
| 1956 | 11 |
| 1957 | 13 |
| 1958 | 17 |
| 1959 | 20 |
| 1960 | 30 |
| 1961 | 23 |
| 1962 | 23 |
| 1963 | 21 |
| 1964 | 20 |
| 1965 | 22 |
| 1966 | 28 |
| 1967 | 13 |
| 1968 | 13 |
| 1969 | 18 |
| 1970 | 16 |
| 1971 | 12 |
| 1972 | 34 |
| 1973 | 14 |
| 1974 | 18 |
| 1975 | 20 |
| 1976 | 9 |
| 1977 | 19 |
| 1978 | 16 |
| 1979 | 14 |
| 1980 | 18 |
| 1981 | 13 |
| 1982 | 11 |
| 1983 | 29 |
| 1984 | 14 |
| 1985 | 37 |
| 1986 | 27 |
| 1987 | 26 |
| 1988 | 23 |
| 1989 | 22 |
| 1990 | 22 |
| 1991 | 20 |
| 1992 | 11 |
| 1997 | 1 |
| 1998 | 6 |
| 1999 | 11 |
| 2000 | 12 |
| 2001 | 8 |
| 2002 | 23 |
| 2003 | 36 |
| 2004 | 8 |
| 2005 | 9 |
| 2006 | 14 |
| 2007 | 9 |
| 2008 | 13 |
| 2009 | 12 |
| 2010 | 9 |
| 2011 | 9 |
| 2012 | 17 |
| 2013 | 9 |
| 2014 | 11 |
| 2015 | 34 |
| 2016 | 9 |
| 2017 | 12 |
| 2018 | 10 |
| 2019 | 22 |
| 2020 | 17 |
| 2021 | 25 |
| 2022 | 22 |
| 2023 | 16 |
| 2024 | 7 |
| 2025 | 21 |
| 2026 | 34 |
All-Time Record Progression
5 new records| Date | Kind | Detail |
|---|---|---|
| 1983-12-22 | Record low minimum temperature | Record low minimum temperature -37.2 C (-35.0 F) |
| 1983-12-24 | Record low minimum temperature | Record low minimum temperature -38.3 C (-36.9 F) |
| 1988-06-05 | Record high minimum temperature | Record high minimum temperature 18.9 C (66.0 F) |
| 1989-02-02 | Record low maximum temperature | Record low maximum temperature -29.4 C (-20.9 F) |
| 2024-01-13 | Record low minimum temperature | Record low minimum temperature -40.5 C (-40.9 F) |
Wettest Day of Each Month
Jun: 50.0 mm (2.0 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 12.7 mm (0.5 in) | 31 January 1972 |
| Feb | 11.4 mm (0.4 in) | 28 February 1980 |
| Mar | 19.1 mm (0.8 in) | 13 March 1977 |
| Apr | 27.7 mm (1.1 in) | 25 April 1975 |
| May | 27.9 mm (1.1 in) | 25 May 1980 |
| Jun | 50.0 mm (2.0 in) | 24 June 1958 |
| Jul | 36.6 mm (1.4 in) | 17 July 1987 |
| Aug | 22.6 mm (0.9 in) | 12 August 1969 |
| Sep | 33.3 mm (1.3 in) | 11 September 1976 |
| Oct | 29.2 mm (1.1 in) | 14 October 1983 |
| Nov | 20.1 mm (0.8 in) | 15 November 1952 |
| Dec | 19.3 mm (0.8 in) | 23 December 1955 |
Period of Record Coverage
1940 to 2026| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1940 | 246 | 67% | No |
| 1941 | 354 | 97% | Yes |
| 1942 | 364 | 100% | Yes |
| 1943 | 365 | 100% | Yes |
| 1944 | 364 | 99% | Yes |
| 1945 | 363 | 99% | Yes |
| 1946 | 364 | 100% | Yes |
| 1947 | 364 | 100% | Yes |
| 1948 | 366 | 100% | Yes |
| 1949 | 363 | 99% | Yes |
| 1950 | 362 | 99% | Yes |
| 1951 | 358 | 98% | Yes |
| 1952 | 366 | 100% | Yes |
| 1953 | 365 | 100% | Yes |
| 1954 | 361 | 99% | Yes |
| 1955 | 362 | 99% | 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 | 349 | 96% | Yes |
| 1974 | 360 | 99% | Yes |
| 1975 | 365 | 100% | Yes |
| 1976 | 365 | 100% | Yes |
| 1977 | 365 | 100% | Yes |
| 1978 | 365 | 100% | Yes |
| 1979 | 339 | 93% | Yes |
| 1980 | 361 | 99% | Yes |
| 1981 | 347 | 95% | Yes |
| 1982 | 351 | 96% | Yes |
| 1983 | 357 | 98% | Yes |
| 1984 | 365 | 100% | Yes |
| 1985 | 360 | 99% | Yes |
| 1986 | 360 | 99% | Yes |
| 1987 | 357 | 98% | Yes |
| 1988 | 363 | 99% | Yes |
| 1989 | 362 | 99% | Yes |
| 1990 | 360 | 99% | Yes |
| 1991 | 360 | 99% | Yes |
| 1992 | 214 | 58% | No |
| 1997 | 186 | 51% | No |
| 1998 | 357 | 98% | Yes |
| 1999 | 361 | 99% | Yes |
| 2000 | 362 | 99% | Yes |
| 2001 | 365 | 100% | Yes |
| 2002 | 364 | 100% | Yes |
| 2003 | 362 | 99% | Yes |
| 2004 | 366 | 100% | Yes |
| 2005 | 364 | 100% | Yes |
| 2006 | 365 | 100% | Yes |
| 2007 | 365 | 100% | Yes |
| 2008 | 366 | 100% | Yes |
| 2009 | 365 | 100% | Yes |
| 2010 | 365 | 100% | Yes |
| 2011 | 365 | 100% | Yes |
| 2012 | 366 | 100% | Yes |
| 2013 | 365 | 100% | Yes |
| 2014 | 365 | 100% | Yes |
| 2015 | 365 | 100% | Yes |
| 2016 | 366 | 100% | Yes |
| 2017 | 365 | 100% | Yes |
| 2018 | 365 | 100% | Yes |
| 2019 | 365 | 100% | Yes |
| 2020 | 366 | 100% | Yes |
| 2021 | 365 | 100% | Yes |
| 2022 | 363 | 99% | Yes |
| 2023 | 359 | 98% | Yes |
| 2024 | 366 | 100% | Yes |
| 2025 | 365 | 100% | Yes |
| 2026 | 286 | 78% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 5 October 2026 | Dillon AP, US | daily high min (Provisional) | 10.0 C (50.0 F) | 0.6 C (1.1 F) | 79 years | 32 of 100 (Routine) |
| 5 October 2026 | Dillon AP, US | daily high max (Provisional) | 28.9 C (84.0 F) | 2.2 C (4.0 F) | 68 years | 31 of 100 (Routine) |
| 4 October 2026 | Dillon AP, US | daily high max (Provisional) | 27.8 C (82.0 F) | 0.6 C (1.1 F) | 45 years | 21 of 100 (Routine) |
| 22 August 2026 | Dillon AP, US | daily high min (Provisional) | 13.9 C (57.0 F) | 0.6 C (1.1 F) | 55 years | 26 of 100 (Routine) |
| 17 July 2026 | Dillon AP, US | daily high min | 16.7 C (62.1 F) | 1.1 C (2.0 F) | 19 years | 16 of 100 (Routine) |
| 12 July 2026 | Dillon AP, US | daily high min | 15.0 C (59.0 F) | 1.1 C (2.0 F) | 12 years | 14 of 100 (Routine) |
| 28 June 2026 | Dillon AP, US | daily low max | 7.2 C (45.0 F) | 6.7 C (12.1 F) | 72 years | 41 of 100 (Notable) |
| 28 June 2026 | Dillon AP, US | daily rain (Tie) | 11.7 mm (0.5 in) | tie | 67 years | 7 of 100 (Routine) |
| 27 June 2026 | Dillon AP, US | daily rain | 29.7 mm (1.2 in) | 15.0 mm (0.6 in) | 81 years | 57 of 100 (Notable) |
| 16 June 2026 | Dillon AP, US | daily high min | 14.4 C (57.9 F) | 2.2 C (4.0 F) | 36 years | 25 of 100 (Routine) |
| 17 May 2026 | Dillon AP, US | daily low min (Tie) | -3.3 C (26.1 F) | tie | 65 years | 6 of 100 (Routine) |
| 12 May 2026 | Dillon AP, US | daily high max | 29.4 C (84.9 F) | 0.5 C (0.9 F) | 84 years | 33 of 100 (Routine) |
| 10 May 2026 | Dillon AP, US | daily high max (Tie) | 27.2 C (81.0 F) | tie | 65 years | 6 of 100 (Routine) |
| 16 April 2026 | Dillon AP, US | daily low max | 0.0 C (32.0 F) | 0.6 C (1.1 F) | 84 years | 34 of 100 (Routine) |
| 7 April 2026 | Dillon AP, US | daily high max (Tie) | 21.1 C (70.0 F) | tie | 48 years | 5 of 100 (Routine) |
| 25 March 2026 | Dillon AP, US | daily high max | 21.1 C (70.0 F) | 1.1 C (2.0 F) | 65 years | 28 of 100 (Routine) |
| 25 March 2026 | Dillon AP, US | daily high min | 4.4 C (39.9 F) | 0.5 C (0.9 F) | 0 years | 8 of 100 (Routine) |
| 24 March 2026 | Dillon AP, US | daily high max | 20.0 C (68.0 F) | 0.6 C (1.1 F) | 69 years | 28 of 100 (Routine) |
| 24 March 2026 | Dillon AP, US | daily high min | 5.6 C (42.1 F) | 2.3 C (4.1 F) | 28 years | 19 of 100 (Routine) |
| 21 March 2026 | Dillon AP, US | daily high max | 22.2 C (72.0 F) | 3.3 C (5.9 F) | 21 years | 19 of 100 (Routine) |
Climate Trend
78 complete years, 1941 to 2025| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1941 | 6.6 C | +0.61 C |
| 1942 | 5.3 C | -0.75 C |
| 1943 | 6.0 C | -0.04 C |
| 1944 | 5.7 C | -0.36 C |
| 1945 | 5.9 C | -0.14 C |
| 1946 | 6.2 C | +0.22 C |
| 1947 | 6.0 C | -0.01 C |
| 1948 | 4.7 C | -1.31 C |
| 1949 | 5.4 C | -0.60 C |
| 1950 | 5.4 C | -0.63 C |
| 1951 | 4.5 C | -1.51 C |
| 1952 | 5.4 C | -0.67 C |
| 1953 | 7.1 C | +1.04 C |
| 1954 | 6.3 C | +0.31 C |
| 1955 | 4.3 C | -1.69 C |
| 1956 | 5.9 C | -0.17 C |
| 1957 | 5.5 C | -0.56 C |
| 1958 | 7.0 C | +0.93 C |
| 1959 | 5.6 C | -0.41 C |
| 1960 | 5.7 C | -0.32 C |
| 1961 | 6.8 C | +0.79 C |
| 1962 | 6.0 C | -0.02 C |
| 1963 | 6.7 C | +0.66 C |
| 1964 | 5.6 C | -0.44 C |
| 1965 | 6.1 C | +0.05 C |
| 1966 | 7.0 C | +0.93 C |
| 1967 | 6.4 C | +0.39 C |
| 1968 | 5.5 C | -0.48 C |
| 1969 | 5.4 C | -0.61 C |
| 1970 | 6.1 C | +0.06 C |
| 1971 | 5.8 C | -0.26 C |
| 1972 | 5.8 C | -0.19 C |
| 1974 | 6.4 C | +0.35 C |
| 1975 | 4.7 C | -1.30 C |
| 1976 | 6.4 C | +0.35 C |
| 1977 | 6.0 C | -0.04 C |
| 1978 | 5.2 C | -0.79 C |
| 1979 | 5.4 C | -0.60 C |
| 1980 | 6.2 C | +0.14 C |
| 1981 | 7.0 C | +0.94 C |
| 1982 | 4.9 C | -1.15 C |
| 1983 | 5.8 C | -0.21 C |
| 1984 | 5.4 C | -0.58 C |
| 1985 | 4.3 C | -1.70 C |
| 1986 | 6.9 C | +0.89 C |
| 1987 | 7.1 C | +1.05 C |
| 1988 | 7.2 C | +1.18 C |
| 1989 | 5.8 C | -0.26 C |
| 1990 | 6.7 C | +0.66 C |
| 1991 | 6.8 C | +0.74 C |
| 1998 | 6.1 C | +0.09 C |
| 1999 | 6.5 C | +0.49 C |
| 2000 | 6.0 C | -0.04 C |
| 2001 | 6.6 C | +0.56 C |
| 2002 | 5.4 C | -0.60 C |
| 2003 | 6.8 C | +0.78 C |
| 2004 | 6.7 C | +0.65 C |
| 2005 | 6.4 C | +0.33 C |
| 2006 | 6.9 C | +0.83 C |
| 2007 | 6.7 C | +0.71 C |
| 2008 | 5.6 C | -0.43 C |
| 2009 | 5.6 C | -0.40 C |
| 2010 | 5.6 C | -0.43 C |
| 2011 | 5.7 C | -0.32 C |
| 2012 | 7.3 C | +1.32 C |
| 2013 | 6.5 C | +0.44 C |
| 2014 | 6.4 C | +0.41 C |
| 2015 | 7.8 C | +1.77 C |
| 2016 | 7.1 C | +1.03 C |
| 2017 | 6.4 C | +0.36 C |
| 2018 | 5.3 C | -0.77 C |
| 2019 | 4.2 C | -1.81 C |
| 2020 | 6.1 C | +0.04 C |
| 2021 | 6.6 C | +0.60 C |
| 2022 | 5.2 C | -0.81 C |
| 2023 | 5.4 C | -0.67 C |
| 2024 | 6.7 C | +0.69 C |
| 2025 | 7.0 C | +1.00 C |
The annual mean temperature here has risen by 0.07 C (0.00 to 0.14) per decade over 1941 to 2025. In Fahrenheit: 0.12 F (0.01 to 0.24) per decade. The slope is a straight line fitted to 78 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.07 C (0.00 to 0.14) per decade | 0.12 F (0.01 to 0.24) per decade | 1941 to 2025 | 78 | Rise |
| Mean daily maximum | 0.02 C (-0.06 to 0.10) per decade | 0.04 F (-0.10 to 0.17) per decade | 1941 to 2025 | 78 | Not clearly different from zero |
| Mean daily minimum | 0.1 C (0.1 to 0.2) per decade | 0.2 F (0.1 to 0.3) per decade | 1941 to 2025 | 78 | 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
1940 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 38.9 C (102.0 F) | 1940 | 35.0 C (95.0 F) | 83 |
| Coldest night (TNn) | -40.5 C (-40.9 F) | 2024 | -30.0 C (-22.0 F) | 83 |
| Wettest day (Rx1day) | 50.0 mm (2.0 in) | 1958 | 21.0 mm (0.8 in) | 82 |
| Wettest five days (Rx5day) | 69.6 mm (2.7 in) | 1987 | 34.4 mm (1.4 in) | 82 |
| Longest dry spell (CDD) | 112 days | 2022 | 43 days | 82 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1940 | 38.9 C (102.0 F) |
| 1941 | 35.0 C (95.0 F) |
| 1942 | 35.6 C (96.1 F) |
| 1943 | 35.6 C (96.1 F) |
| 1944 | 35.0 C (95.0 F) |
| 1945 | 35.0 C (95.0 F) |
| 1946 | 34.4 C (93.9 F) |
| 1947 | 34.4 C (93.9 F) |
| 1948 | 32.8 C (91.0 F) |
| 1949 | 36.1 C (97.0 F) |
| 1950 | 35.0 C (95.0 F) |
| 1951 | 37.2 C (99.0 F) |
| 1952 | 33.9 C (93.0 F) |
| 1953 | 36.1 C (97.0 F) |
| 1954 | 36.7 C (98.1 F) |
| 1955 | 35.6 C (96.1 F) |
| 1956 | 35.6 C (96.1 F) |
| 1957 | 35.0 C (95.0 F) |
| 1958 | 35.6 C (96.1 F) |
| 1959 | 35.6 C (96.1 F) |
| 1960 | 38.3 C (100.9 F) |
| 1961 | 38.3 C (100.9 F) |
| 1962 | 32.2 C (90.0 F) |
| 1963 | 35.6 C (96.1 F) |
| 1964 | 34.4 C (93.9 F) |
| 1965 | 32.8 C (91.0 F) |
| 1966 | 36.1 C (97.0 F) |
| 1967 | 35.0 C (95.0 F) |
| 1968 | 33.9 C (93.0 F) |
| 1969 | 36.1 C (97.0 F) |
| 1970 | 36.7 C (98.1 F) |
| 1971 | 35.6 C (96.1 F) |
| 1972 | 36.7 C (98.1 F) |
| 1973 | 35.0 C (95.0 F) |
| 1974 | 35.0 C (95.0 F) |
| 1975 | 35.0 C (95.0 F) |
| 1976 | 33.3 C (91.9 F) |
| 1977 | 34.4 C (93.9 F) |
| 1978 | 35.0 C (95.0 F) |
| 1979 | 35.0 C (95.0 F) |
| 1980 | 32.8 C (91.0 F) |
| 1981 | 35.6 C (96.1 F) |
| 1982 | 33.3 C (91.9 F) |
| 1983 | 34.4 C (93.9 F) |
| 1984 | 32.2 C (90.0 F) |
| 1985 | 36.7 C (98.1 F) |
| 1986 | 34.4 C (93.9 F) |
| 1987 | 32.2 C (90.0 F) |
| 1988 | 36.7 C (98.1 F) |
| 1989 | 35.0 C (95.0 F) |
| 1990 | 36.7 C (98.1 F) |
| 1991 | 35.6 C (96.1 F) |
| 1992 | 34.4 C (93.9 F) |
| 1997 | 32.2 C (90.0 F) |
| 1998 | 35.0 C (95.0 F) |
| 1999 | 33.3 C (91.9 F) |
| 2000 | 35.6 C (96.1 F) |
| 2001 | 36.1 C (97.0 F) |
| 2002 | 38.9 C (102.0 F) |
| 2003 | 37.2 C (99.0 F) |
| 2004 | 33.9 C (93.0 F) |
| 2005 | 33.9 C (93.0 F) |
| 2006 | 36.7 C (98.1 F) |
| 2007 | 36.1 C (97.0 F) |
| 2008 | 35.6 C (96.1 F) |
| 2009 | 35.0 C (95.0 F) |
| 2010 | 33.9 C (93.0 F) |
| 2011 | 33.9 C (93.0 F) |
| 2012 | 35.0 C (95.0 F) |
| 2013 | 34.4 C (93.9 F) |
| 2014 | 33.3 C (91.9 F) |
| 2015 | 36.7 C (98.1 F) |
| 2016 | 33.9 C (93.0 F) |
| 2017 | 35.0 C (95.0 F) |
| 2018 | 35.6 C (96.1 F) |
| 2019 | 33.3 C (91.9 F) |
| 2020 | 35.0 C (95.0 F) |
| 2021 | 35.0 C (95.0 F) |
| 2022 | 36.1 C (97.0 F) |
| 2023 | 35.0 C (95.0 F) |
| 2024 | 35.0 C (95.0 F) |
| 2025 | 35.0 C (95.0 F) |
| 2026 | 37.2 C (99.0 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1940 | -23.9 C (-11.0 F) |
| 1941 | -30.0 C (-22.0 F) |
| 1942 | -33.9 C (-29.0 F) |
| 1943 | -33.9 C (-29.0 F) |
| 1944 | -28.9 C (-20.0 F) |
| 1945 | -27.8 C (-18.0 F) |
| 1946 | -25.0 C (-13.0 F) |
| 1947 | -28.3 C (-18.9 F) |
| 1948 | -30.6 C (-23.1 F) |
| 1949 | -36.1 C (-33.0 F) |
| 1950 | -31.7 C (-25.1 F) |
| 1951 | -35.6 C (-32.1 F) |
| 1952 | -31.1 C (-24.0 F) |
| 1953 | -20.6 C (-5.1 F) |
| 1954 | -29.4 C (-20.9 F) |
| 1955 | -33.9 C (-29.0 F) |
| 1956 | -31.7 C (-25.1 F) |
| 1957 | -36.1 C (-33.0 F) |
| 1958 | -22.8 C (-9.0 F) |
| 1959 | -30.6 C (-23.1 F) |
| 1960 | -30.6 C (-23.1 F) |
| 1961 | -29.4 C (-20.9 F) |
| 1962 | -34.4 C (-29.9 F) |
| 1963 | -33.9 C (-29.0 F) |
| 1964 | -32.8 C (-27.0 F) |
| 1965 | -24.4 C (-11.9 F) |
| 1966 | -24.4 C (-11.9 F) |
| 1967 | -27.8 C (-18.0 F) |
| 1968 | -32.2 C (-26.0 F) |
| 1969 | -33.3 C (-27.9 F) |
| 1970 | -28.3 C (-18.9 F) |
| 1971 | -29.4 C (-20.9 F) |
| 1972 | -36.1 C (-33.0 F) |
| 1973 | -33.9 C (-29.0 F) |
| 1974 | -32.2 C (-26.0 F) |
| 1975 | -27.8 C (-18.0 F) |
| 1976 | -26.7 C (-16.1 F) |
| 1977 | -30.0 C (-22.0 F) |
| 1978 | -34.4 C (-29.9 F) |
| 1979 | -33.9 C (-29.0 F) |
| 1980 | -34.4 C (-29.9 F) |
| 1981 | -33.3 C (-27.9 F) |
| 1982 | -31.7 C (-25.1 F) |
| 1983 | -38.3 C (-36.9 F) |
| 1984 | -28.9 C (-20.0 F) |
| 1985 | -32.8 C (-27.0 F) |
| 1986 | -28.3 C (-18.9 F) |
| 1987 | -28.3 C (-18.9 F) |
| 1988 | -25.0 C (-13.0 F) |
| 1989 | -36.7 C (-34.1 F) |
| 1990 | -36.7 C (-34.1 F) |
| 1991 | -27.8 C (-18.0 F) |
| 1992 | -18.9 C (-2.0 F) |
| 1997 | -21.7 C (-7.1 F) |
| 1998 | -32.8 C (-27.0 F) |
| 1999 | -20.6 C (-5.1 F) |
| 2000 | -24.4 C (-11.9 F) |
| 2001 | -22.2 C (-8.0 F) |
| 2002 | -26.1 C (-15.0 F) |
| 2003 | -28.9 C (-20.0 F) |
| 2004 | -33.9 C (-29.0 F) |
| 2005 | -27.8 C (-18.0 F) |
| 2006 | -27.8 C (-18.0 F) |
| 2007 | -29.4 C (-20.9 F) |
| 2008 | -32.8 C (-27.0 F) |
| 2009 | -29.4 C (-20.9 F) |
| 2010 | -30.0 C (-22.0 F) |
| 2011 | -27.2 C (-17.0 F) |
| 2012 | -21.7 C (-7.1 F) |
| 2013 | -31.0 C (-23.8 F) |
| 2014 | -33.2 C (-27.8 F) |
| 2015 | -22.1 C (-7.8 F) |
| 2016 | -31.6 C (-24.9 F) |
| 2017 | -29.9 C (-21.8 F) |
| 2018 | -31.0 C (-23.8 F) |
| 2019 | -30.5 C (-22.9 F) |
| 2020 | -22.7 C (-8.9 F) |
| 2021 | -26.6 C (-15.9 F) |
| 2022 | -29.9 C (-21.8 F) |
| 2023 | -33.2 C (-27.8 F) |
| 2024 | -40.5 C (-40.9 F) |
| 2025 | -28.8 C (-19.8 F) |
| 2026 | -18.9 C (-2.0 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1940 | 24.6 mm (1.0 in) |
| 1941 | 21.1 mm (0.8 in) |
| 1942 | 10.7 mm (0.4 in) |
| 1943 | 21.6 mm (0.9 in) |
| 1944 | 31.8 mm (1.3 in) |
| 1945 | 13.5 mm (0.5 in) |
| 1946 | 22.6 mm (0.9 in) |
| 1947 | 16.5 mm (0.6 in) |
| 1948 | 22.9 mm (0.9 in) |
| 1949 | 21.8 mm (0.9 in) |
| 1950 | 21.3 mm (0.8 in) |
| 1951 | 16.5 mm (0.6 in) |
| 1952 | 20.1 mm (0.8 in) |
| 1953 | 16.0 mm (0.6 in) |
| 1954 | 18.0 mm (0.7 in) |
| 1955 | 24.9 mm (1.0 in) |
| 1956 | 19.8 mm (0.8 in) |
| 1957 | 27.9 mm (1.1 in) |
| 1958 | 50.0 mm (2.0 in) |
| 1959 | 31.2 mm (1.2 in) |
| 1960 | 19.6 mm (0.8 in) |
| 1961 | 20.8 mm (0.8 in) |
| 1962 | 24.1 mm (0.9 in) |
| 1963 | 18.8 mm (0.7 in) |
| 1964 | 38.1 mm (1.5 in) |
| 1965 | 24.1 mm (0.9 in) |
| 1966 | 23.9 mm (0.9 in) |
| 1967 | 20.8 mm (0.8 in) |
| 1968 | 20.8 mm (0.8 in) |
| 1969 | 22.6 mm (0.9 in) |
| 1970 | 20.1 mm (0.8 in) |
| 1971 | 25.4 mm (1.0 in) |
| 1972 | 12.7 mm (0.5 in) |
| 1973 | 29.2 mm (1.1 in) |
| 1974 | 19.3 mm (0.8 in) |
| 1975 | 34.5 mm (1.4 in) |
| 1976 | 33.3 mm (1.3 in) |
| 1977 | 19.1 mm (0.8 in) |
| 1978 | 25.1 mm (1.0 in) |
| 1979 | 14.7 mm (0.6 in) |
| 1980 | 27.9 mm (1.1 in) |
| 1981 | 21.3 mm (0.8 in) |
| 1982 | 24.1 mm (0.9 in) |
| 1983 | 32.0 mm (1.3 in) |
| 1984 | 19.1 mm (0.8 in) |
| 1985 | 14.7 mm (0.6 in) |
| 1986 | 22.6 mm (0.9 in) |
| 1987 | 36.6 mm (1.4 in) |
| 1988 | 27.7 mm (1.1 in) |
| 1989 | 16.3 mm (0.6 in) |
| 1990 | 23.6 mm (0.9 in) |
| 1991 | 16.8 mm (0.7 in) |
| 1992 | 18.0 mm (0.7 in) |
| 1997 | n/a |
| 1998 | 12.2 mm (0.5 in) |
| 1999 | 20.6 mm (0.8 in) |
| 2000 | 18.8 mm (0.7 in) |
| 2001 | 26.9 mm (1.1 in) |
| 2002 | 16.3 mm (0.6 in) |
| 2003 | 17.0 mm (0.7 in) |
| 2004 | 21.3 mm (0.8 in) |
| 2005 | 19.8 mm (0.8 in) |
| 2006 | 21.8 mm (0.9 in) |
| 2007 | 40.1 mm (1.6 in) |
| 2008 | 34.3 mm (1.4 in) |
| 2009 | 26.4 mm (1.0 in) |
| 2010 | 19.6 mm (0.8 in) |
| 2011 | 21.6 mm (0.9 in) |
| 2012 | 11.4 mm (0.4 in) |
| 2013 | 17.8 mm (0.7 in) |
| 2014 | 21.1 mm (0.8 in) |
| 2015 | 25.4 mm (1.0 in) |
| 2016 | 15.0 mm (0.6 in) |
| 2017 | 26.2 mm (1.0 in) |
| 2018 | 17.0 mm (0.7 in) |
| 2019 | 17.3 mm (0.7 in) |
| 2020 | 15.0 mm (0.6 in) |
| 2021 | 9.1 mm (0.36 in) |
| 2022 | 16.5 mm (0.6 in) |
| 2023 | 10.2 mm (0.4 in) |
| 2024 | 12.4 mm (0.5 in) |
| 2025 | 7.9 mm (0.31 in) |
| 2026 | 29.7 mm (1.2 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1940 | 35.2 mm (1.4 in) |
| 1941 | 36.6 mm (1.4 in) |
| 1942 | 19.4 mm (0.8 in) |
| 1943 | 32.1 mm (1.3 in) |
| 1944 | 68.3 mm (2.7 in) |
| 1945 | 35.6 mm (1.4 in) |
| 1946 | 27.4 mm (1.1 in) |
| 1947 | 45.5 mm (1.8 in) |
| 1948 | 60.3 mm (2.4 in) |
| 1949 | 42.2 mm (1.7 in) |
| 1950 | 24.1 mm (0.9 in) |
| 1951 | 20.9 mm (0.8 in) |
| 1952 | 32.5 mm (1.3 in) |
| 1953 | 27.2 mm (1.1 in) |
| 1954 | 25.1 mm (1.0 in) |
| 1955 | 27.9 mm (1.1 in) |
| 1956 | 21.3 mm (0.8 in) |
| 1957 | 44.7 mm (1.8 in) |
| 1958 | 50.0 mm (2.0 in) |
| 1959 | 61.4 mm (2.4 in) |
| 1960 | 32.2 mm (1.3 in) |
| 1961 | 31.5 mm (1.2 in) |
| 1962 | 29.9 mm (1.2 in) |
| 1963 | 39.7 mm (1.6 in) |
| 1964 | 57.5 mm (2.3 in) |
| 1965 | 45.9 mm (1.8 in) |
| 1966 | 31.0 mm (1.2 in) |
| 1967 | 44.9 mm (1.8 in) |
| 1968 | 34.0 mm (1.3 in) |
| 1969 | 50.1 mm (2.0 in) |
| 1970 | 30.2 mm (1.2 in) |
| 1971 | 32.2 mm (1.3 in) |
| 1972 | 24.9 mm (1.0 in) |
| 1973 | 29.2 mm (1.1 in) |
| 1974 | 32.8 mm (1.3 in) |
| 1975 | 47.2 mm (1.9 in) |
| 1976 | 35.6 mm (1.4 in) |
| 1977 | 26.7 mm (1.1 in) |
| 1978 | 36.1 mm (1.4 in) |
| 1979 | 27.9 mm (1.1 in) |
| 1980 | 49.7 mm (2.0 in) |
| 1981 | 38.3 mm (1.5 in) |
| 1982 | 24.9 mm (1.0 in) |
| 1983 | 43.2 mm (1.7 in) |
| 1984 | 23.4 mm (0.9 in) |
| 1985 | 36.5 mm (1.4 in) |
| 1986 | 30.2 mm (1.2 in) |
| 1987 | 69.6 mm (2.7 in) |
| 1988 | 56.2 mm (2.2 in) |
| 1989 | 29.5 mm (1.2 in) |
| 1990 | 38.1 mm (1.5 in) |
| 1991 | 24.7 mm (1.0 in) |
| 1992 | 42.9 mm (1.7 in) |
| 1997 | n/a |
| 1998 | 27.2 mm (1.1 in) |
| 1999 | 50.1 mm (2.0 in) |
| 2000 | 35.3 mm (1.4 in) |
| 2001 | 44.7 mm (1.8 in) |
| 2002 | 38.4 mm (1.5 in) |
| 2003 | 25.7 mm (1.0 in) |
| 2004 | 35.0 mm (1.4 in) |
| 2005 | 44.7 mm (1.8 in) |
| 2006 | 34.8 mm (1.4 in) |
| 2007 | 52.6 mm (2.1 in) |
| 2008 | 45.3 mm (1.8 in) |
| 2009 | 30.9 mm (1.2 in) |
| 2010 | 31.5 mm (1.2 in) |
| 2011 | 53.1 mm (2.1 in) |
| 2012 | 21.1 mm (0.8 in) |
| 2013 | 36.3 mm (1.4 in) |
| 2014 | 33.7 mm (1.3 in) |
| 2015 | 36.6 mm (1.4 in) |
| 2016 | 34.0 mm (1.3 in) |
| 2017 | 41.7 mm (1.6 in) |
| 2018 | 45.7 mm (1.8 in) |
| 2019 | 25.4 mm (1.0 in) |
| 2020 | 28.5 mm (1.1 in) |
| 2021 | 15.0 mm (0.6 in) |
| 2022 | 19.8 mm (0.8 in) |
| 2023 | 14.2 mm (0.6 in) |
| 2024 | 12.7 mm (0.5 in) |
| 2025 | 11.7 mm (0.5 in) |
| 2026 | 43.2 mm (1.7 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1940 | 34 days |
| 1941 | 42 days |
| 1942 | 31 days |
| 1943 | 44 days |
| 1944 | 58 days |
| 1945 | 63 days |
| 1946 | 43 days |
| 1947 | 26 days |
| 1948 | 41 days |
| 1949 | 39 days |
| 1950 | 34 days |
| 1951 | 54 days |
| 1952 | 64 days |
| 1953 | 35 days |
| 1954 | 33 days |
| 1955 | 28 days |
| 1956 | 46 days |
| 1957 | 45 days |
| 1958 | 41 days |
| 1959 | 45 days |
| 1960 | 49 days |
| 1961 | 34 days |
| 1962 | 36 days |
| 1963 | 41 days |
| 1964 | 43 days |
| 1965 | 63 days |
| 1966 | 26 days |
| 1967 | 26 days |
| 1968 | 46 days |
| 1969 | 42 days |
| 1970 | 44 days |
| 1971 | 29 days |
| 1972 | 28 days |
| 1973 | 31 days |
| 1974 | 43 days |
| 1975 | 51 days |
| 1976 | 81 days |
| 1977 | 43 days |
| 1978 | 40 days |
| 1979 | 43 days |
| 1980 | 31 days |
| 1981 | 35 days |
| 1982 | 27 days |
| 1983 | 72 days |
| 1984 | 40 days |
| 1985 | 39 days |
| 1986 | 40 days |
| 1987 | 68 days |
| 1988 | 74 days |
| 1989 | 64 days |
| 1990 | 63 days |
| 1991 | 41 days |
| 1992 | 39 days |
| 1997 | n/a |
| 1998 | 36 days |
| 1999 | 34 days |
| 2000 | 40 days |
| 2001 | 48 days |
| 2002 | 58 days |
| 2003 | 33 days |
| 2004 | 56 days |
| 2005 | 70 days |
| 2006 | 63 days |
| 2007 | 38 days |
| 2008 | 40 days |
| 2009 | 56 days |
| 2010 | 23 days |
| 2011 | 66 days |
| 2012 | 48 days |
| 2013 | 47 days |
| 2014 | 38 days |
| 2015 | 39 days |
| 2016 | 58 days |
| 2017 | 29 days |
| 2018 | 51 days |
| 2019 | 40 days |
| 2020 | 53 days |
| 2021 | 66 days |
| 2022 | 112 days |
| 2023 | 66 days |
| 2024 | 43 days |
| 2025 | 45 days |
| 2026 | 63 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
78 years with a frostAcross 78 years with a frost, the median last spring frost at Dillon AP falls on 4 June and the median first autumn frost on 13 September, which leaves a median of 103 days between them.
In 1990 to 2025 the median growing season was 110 days. That is 6 days more than in 1941 to 1970.
Fitted over all years, the growing season changes by +1.2 days per decade at this station.
| Measure | Median, all years | Earliest period (1941 to 1970) | Recent period (1990 to 2025) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 4 June | 3 June | 3 June | no change | -0.1 days per decade |
| First autumn frost | 13 September | 11 September | 19 September | 8 days later | +1.1 days per decade |
| Growing days | 103 days | 104 days | 110 days | 6 days more | +1.2 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
79 years, 1940 to 2025A day with at least 20.8 mm (0.8 in) of rain is expected about once in 2 years. A day with at least 43.8 mm (1.7 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 20.8 mm (0.8 in) | |
| 5 years | 27.3 mm (1.1 in) | |
| 10 years | 31.4 mm (1.2 in) | |
| 25 years | 36.5 mm (1.4 in) | |
| 50 years | 40.2 mm (1.6 in) | |
| 100 years | 43.8 mm (1.7 in) | Longer than the 79 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, 79 years of values from 1940 to 2025.
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: 50.0 mm (2.0 in) in 1958; 40.1 mm (1.6 in) in 2007; 38.1 mm (1.5 in) in 1964.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Climate Twins
2011 to 2025 against 1961 to 1990Over 2011 to 2025, Dillon AP had a mean temperature of 6.2 C (43.2 F) and 185.9 mm (7.3 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Saratoga (United States, 628 km away), Burris (United States, 335 km away) and Great Sand Dunes Np & Preserve (United States, 1,021 km away).
| Twin station | Country | Distance away | Mean temperature, 1961-1990 | Rain a year, 1961-1990 | Climate difference |
|---|---|---|---|---|---|
| Saratoga | United States | 628 km (390 mi) | 6.0 C (42.8 F) | 249.4 mm (9.8 in) | 0.85 |
| Burris | United States | 335 km (208 mi) | 6.3 C (43.3 F) | 224.3 mm (8.8 in) | 0.95 |
| Great Sand Dunes Np & Preserve | United States | 1,021 km (634 mi) | 6.4 C (43.5 F) | 273.8 mm (10.8 in) | 0.96 |
Twins are stations, not cities. A twin is one of the three stations at least 100 km away whose earlier climate is closest to this station's recent one, so a close match does not mean the two places look alike in other ways. A station move or a gap in a record can change that station's averages. The list describes past climate; it is not a forecast and does not say what caused any change. How twins are found, and a search for any station.
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 2026-10-16 (16 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-16).