Fontenelle Dam Weather Records (USC00483396)
Record envelope, standing records and threshold days for Fontenelle Dam (USC00483396), Wyoming, United States, with 64 years of record.
Key Facts for Fontenelle Dam
- Fontenelle Dam (USC00483396) is a weather station in Wyoming, United States at 41.99 latitude and -110.06 longitude, 1,977 m (6,485 ft) above sea level.
- The station reports from 1963 to 2026, 64 years of record.
- 1,464 records set at Fontenelle Dam still stand.
- Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
- Fontenelle Dam tied a daily record high minimum temperature of 6.7 C (44.1 F) on 6 October 2026 (provisional).
Provisional Records
Records set in the last 60 days are provisional until they clear the revision window.
About the Station
- Location: Wyoming, United States, 41.99 latitude, -110.06 longitude.
- Elevation: 1,977 m (6,485 ft).
- Period of record: 1963 to 2026, 64 years.
- Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
30 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 11.7 C (53.1 F) | -41.7 C (-43.1 F) | 10.0 C (50.0 F) | -21.1 C (-6.0 F) |
| Feb | 13.9 C (57.0 F) | -43.3 C (-45.9 F) | 11.7 C (53.1 F) | -13.9 C (7.0 F) |
| Mar | 23.9 C (75.0 F) | -36.1 C (-33.0 F) | 23.9 C (75.0 F) | -13.9 C (7.0 F) |
| Apr | 26.1 C (79.0 F) | -22.8 C (-9.0 F) | 22.8 C (73.0 F) | -12.2 C (10.0 F) |
| May | 30.6 C (87.1 F) | -14.4 C (6.1 F) | 28.3 C (82.9 F) | -8.3 C (17.1 F) |
| Jun | 34.4 C (93.9 F) | -10.0 C (14.0 F) | 30.6 C (87.1 F) | -6.1 C (21.0 F) |
| Jul | 37.8 C (100.0 F) | -6.1 C (21.0 F) | 36.1 C (97.0 F) | 0.0 C (32.0 F) |
| Aug | 35.0 C (95.0 F) | -8.3 C (17.1 F) | 35.0 C (95.0 F) | -0.6 C (30.9 F) |
| Sep | 33.9 C (93.0 F) | -15.6 C (3.9 F) | 27.8 C (82.0 F) | -0.6 C (30.9 F) |
| Oct | 27.2 C (81.0 F) | -30.6 C (-23.1 F) | 26.7 C (80.1 F) | 1.1 C (34.0 F) |
| Nov | 21.1 C (70.0 F) | -33.9 C (-29.0 F) | n/a | n/a |
| Dec | 15.6 C (60.1 F) | -43.3 C (-45.9 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1963 | 22 |
| 1964 | 18 |
| 1965 | 13 |
| 1966 | 30 |
| 1967 | 14 |
| 1968 | 15 |
| 1969 | 20 |
| 1970 | 19 |
| 1971 | 16 |
| 1972 | 20 |
| 1973 | 17 |
| 1974 | 16 |
| 1975 | 7 |
| 1976 | 15 |
| 1977 | 26 |
| 1978 | 32 |
| 1979 | 30 |
| 1980 | 29 |
| 1981 | 26 |
| 1982 | 12 |
| 1983 | 25 |
| 1984 | 29 |
| 1985 | 32 |
| 1986 | 12 |
| 1987 | 18 |
| 1988 | 18 |
| 1989 | 36 |
| 1990 | 24 |
| 1991 | 12 |
| 1992 | 34 |
| 1993 | 48 |
| 1994 | 9 |
| 1995 | 16 |
| 1996 | 20 |
| 1997 | 29 |
| 1998 | 27 |
| 1999 | 42 |
| 2000 | 40 |
| 2001 | 40 |
| 2002 | 25 |
| 2003 | 25 |
| 2004 | 9 |
| 2005 | 9 |
| 2006 | 12 |
| 2007 | 12 |
| 2008 | 11 |
| 2009 | 14 |
| 2010 | 7 |
| 2011 | 13 |
| 2012 | 39 |
| 2013 | 41 |
| 2014 | 27 |
| 2015 | 41 |
| 2016 | 15 |
| 2017 | 37 |
| 2018 | 15 |
| 2019 | 18 |
| 2020 | 23 |
| 2021 | 32 |
| 2022 | 22 |
| 2023 | 23 |
| 2024 | 11 |
| 2025 | 36 |
| 2026 | 39 |
All-Time Record Progression
4 new records| Date | Kind | Detail |
|---|---|---|
| 2003-02-02 | Record daily snowfall | Record daily snowfall 35.6 cm (14.0 in) |
| 2007-07-22 | Record high maximum temperature | Record high maximum temperature 37.8 C (100.0 F) |
| 2012-08-06 | Record high minimum temperature | Record high minimum temperature 18.3 C (64.9 F) |
| 2026-07-21 | Record high minimum temperature | Record high minimum temperature 18.9 C (66.0 F) |
Wettest Day of Each Month
Sep: 46.2 mm (1.8 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 17.3 mm (0.7 in) | 4 January 2017 |
| Feb | 14.5 mm (0.6 in) | 2 February 2003 |
| Mar | 25.4 mm (1.0 in) | 31 March 2017 |
| Apr | 30.5 mm (1.2 in) | 30 April 1983 |
| May | 37.1 mm (1.5 in) | 9 May 2011 |
| Jun | 35.6 mm (1.4 in) | 17 June 2018 |
| Jul | 38.1 mm (1.5 in) | 20 July 1973 |
| Aug | 27.4 mm (1.1 in) | 19 August 1977 |
| Sep | 46.2 mm (1.8 in) | 14 September 1982 |
| Oct | 25.9 mm (1.0 in) | 1 October 2002 |
| Nov | 13.0 mm (0.5 in) | 10 November 2004 |
| Dec | 13.5 mm (0.5 in) | 9 December 1985 |
Period of Record Coverage
1963 to 2026| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1963 | 178 | 49% | No |
| 1964 | 270 | 74% | No |
| 1965 | 362 | 99% | Yes |
| 1966 | 365 | 100% | Yes |
| 1967 | 364 | 100% | Yes |
| 1968 | 306 | 84% | No |
| 1969 | 256 | 70% | No |
| 1970 | 287 | 79% | No |
| 1971 | 363 | 99% | Yes |
| 1972 | 300 | 82% | No |
| 1973 | 335 | 92% | Yes |
| 1974 | 275 | 75% | No |
| 1975 | 150 | 41% | No |
| 1976 | 365 | 100% | Yes |
| 1977 | 364 | 100% | Yes |
| 1978 | 363 | 99% | Yes |
| 1979 | 364 | 100% | Yes |
| 1980 | 366 | 100% | Yes |
| 1981 | 365 | 100% | Yes |
| 1982 | 364 | 100% | Yes |
| 1983 | 364 | 100% | Yes |
| 1984 | 366 | 100% | Yes |
| 1985 | 365 | 100% | Yes |
| 1986 | 362 | 99% | Yes |
| 1987 | 363 | 99% | Yes |
| 1988 | 365 | 100% | Yes |
| 1989 | 343 | 94% | Yes |
| 1990 | 347 | 95% | Yes |
| 1991 | 359 | 98% | Yes |
| 1992 | 359 | 98% | Yes |
| 1993 | 359 | 98% | Yes |
| 1994 | 359 | 98% | Yes |
| 1995 | 359 | 98% | Yes |
| 1996 | 360 | 98% | Yes |
| 1997 | 364 | 100% | Yes |
| 1998 | 364 | 100% | Yes |
| 1999 | 364 | 100% | Yes |
| 2000 | 363 | 99% | Yes |
| 2001 | 363 | 99% | Yes |
| 2002 | 362 | 99% | Yes |
| 2003 | 356 | 98% | Yes |
| 2004 | 355 | 97% | Yes |
| 2005 | 359 | 98% | Yes |
| 2006 | 355 | 97% | Yes |
| 2007 | 339 | 93% | Yes |
| 2008 | 348 | 95% | Yes |
| 2009 | 325 | 89% | No |
| 2010 | 274 | 75% | No |
| 2011 | 322 | 88% | No |
| 2012 | 366 | 100% | Yes |
| 2013 | 365 | 100% | Yes |
| 2014 | 363 | 99% | Yes |
| 2015 | 365 | 100% | Yes |
| 2016 | 365 | 100% | Yes |
| 2017 | 364 | 100% | Yes |
| 2018 | 363 | 99% | Yes |
| 2019 | 365 | 100% | Yes |
| 2020 | 366 | 100% | Yes |
| 2021 | 365 | 100% | Yes |
| 2022 | 364 | 100% | Yes |
| 2023 | 365 | 100% | Yes |
| 2024 | 366 | 100% | Yes |
| 2025 | 365 | 100% | Yes |
| 2026 | 270 | 74% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 6 October 2026 | Fontenelle Dam, US | daily high min (Tie, Provisional) | 6.7 C (44.1 F) | tie | 11 years | 2 of 100 (Routine) |
| 6 October 2026 | Fontenelle Dam, US | daily high max (Tie, Provisional) | 25.6 C (78.1 F) | tie | 5 years | 1 of 100 (Routine) |
| 4 October 2026 | Fontenelle Dam, US | daily high max (Provisional) | 26.1 C (79.0 F) | 0.5 C (0.9 F) | 63 years | 24 of 100 (Routine) |
| 29 August 2026 | Fontenelle Dam, US | daily rain (Provisional) | 12.2 mm (0.5 in) | 10.2 mm (0.4 in) | 15 years | 20 of 100 (Routine) |
| 21 August 2026 | Fontenelle Dam, US | daily high max (Provisional) | 32.8 C (91.0 F) | 1.1 C (2.0 F) | 16 years | 14 of 100 (Routine) |
| 2 August 2026 | Fontenelle Dam, US | daily high max | 34.4 C (93.9 F) | 1.1 C (2.0 F) | 5 years | 10 of 100 (Routine) |
| 1 August 2026 | Fontenelle Dam, US | monthly high max (Tie) | 35.0 C (95.0 F) | tie | 46 years | 7 of 100 (Routine) |
| 29 July 2026 | Fontenelle Dam, US | daily high min (Tie) | 14.4 C (57.9 F) | tie | 56 years | 5 of 100 (Routine) |
| 27 July 2026 | Fontenelle Dam, US | daily high min | 16.1 C (61.0 F) | 2.8 C (5.0 F) | 5 years | 14 of 100 (Routine) |
| 26 July 2026 | Fontenelle Dam, US | daily high max | 35.6 C (96.1 F) | 3.4 C (6.1 F) | 48 years | 29 of 100 (Routine) |
| 26 July 2026 | Fontenelle Dam, US | daily high min | 17.2 C (63.0 F) | 2.8 C (5.0 F) | 15 years | 17 of 100 (Routine) |
| 21 July 2026 | Fontenelle Dam, US | all-time high min | 18.9 C (66.0 F) | 0.6 C (1.1 F) | 13 years | 31 of 100 (Routine) |
| 20 July 2026 | Fontenelle Dam, US | daily high max | 35.0 C (95.0 F) | 1.1 C (2.0 F) | 60 years | 27 of 100 (Routine) |
| 14 July 2026 | Fontenelle Dam, US | daily high max | 35.0 C (95.0 F) | 1.1 C (2.0 F) | 1 year | 9 of 100 (Routine) |
| 13 July 2026 | Fontenelle Dam, US | daily high max | 36.1 C (97.0 F) | 1.7 C (3.1 F) | 20 years | 16 of 100 (Routine) |
| 12 July 2026 | Fontenelle Dam, US | daily high max | 36.1 C (97.0 F) | 1.7 C (3.1 F) | 1 year | 10 of 100 (Routine) |
| 11 July 2026 | Fontenelle Dam, US | daily high max | 33.9 C (93.0 F) | 0.6 C (1.1 F) | 52 years | 22 of 100 (Routine) |
| 7 July 2026 | Fontenelle Dam, US | daily rain | 5.1 mm (0.20 in) | 2.3 mm (0.09 in) | 8 years | 13 of 100 (Routine) |
| 6 July 2026 | Fontenelle Dam, US | daily high min | 13.3 C (55.9 F) | 0.5 C (0.9 F) | 40 years | 19 of 100 (Routine) |
| 28 June 2026 | Fontenelle Dam, US | daily low max | 17.2 C (63.0 F) | 1.7 C (3.1 F) | 27 years | 17 of 100 (Routine) |
Climate Trend
46 complete years, 1965 to 2025| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1965 | 4.5 C | +1.19 C |
| 1966 | 3.9 C | +0.64 C |
| 1967 | 4.6 C | +1.31 C |
| 1971 | 3.5 C | +0.23 C |
| 1976 | 3.3 C | +0.05 C |
| 1977 | 4.2 C | +0.89 C |
| 1978 | 2.5 C | -0.73 C |
| 1979 | 2.4 C | -0.91 C |
| 1980 | 3.4 C | +0.17 C |
| 1981 | 5.2 C | +1.93 C |
| 1982 | 2.7 C | -0.55 C |
| 1983 | 2.8 C | -0.44 C |
| 1984 | 1.4 C | -1.90 C |
| 1985 | 2.1 C | -1.13 C |
| 1986 | 3.8 C | +0.54 C |
| 1987 | 3.8 C | +0.56 C |
| 1988 | 4.1 C | +0.81 C |
| 1989 | 3.6 C | +0.35 C |
| 1990 | 4.5 C | +1.19 C |
| 1991 | 2.8 C | -0.44 C |
| 1992 | 2.3 C | -0.93 C |
| 1993 | -1.7 C | -4.94 C |
| 1994 | 2.9 C | -0.34 C |
| 1997 | 0.2 C | -3.05 C |
| 1998 | -0.1 C | -3.39 C |
| 1999 | 0.5 C | -2.81 C |
| 2000 | 0.4 C | -2.91 C |
| 2001 | -0.5 C | -3.80 C |
| 2002 | 0.4 C | -2.88 C |
| 2003 | 0.7 C | -2.55 C |
| 2005 | 3.4 C | +0.14 C |
| 2006 | 4.3 C | +1.00 C |
| 2012 | 6.3 C | +3.07 C |
| 2013 | 4.9 C | +1.65 C |
| 2014 | 6.0 C | +2.74 C |
| 2015 | 6.3 C | +3.04 C |
| 2016 | 5.4 C | +2.09 C |
| 2017 | 5.1 C | +1.87 C |
| 2018 | 5.0 C | +1.75 C |
| 2019 | 2.4 C | -0.88 C |
| 2020 | 3.7 C | +0.40 C |
| 2021 | 5.5 C | +2.19 C |
| 2022 | 4.1 C | +0.88 C |
| 2023 | 2.4 C | -0.88 C |
| 2024 | 5.0 C | +1.73 C |
| 2025 | 6.2 C | +2.96 C |
The fitted trend in annual mean temperature here over 1965 to 2025 is 0.2 C (-0.1 to 0.6) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.4 F (-0.2 to 1.0) per decade. The slope is a straight line fitted to 46 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 (-0.1 to 0.6) per decade | 0.4 F (-0.2 to 1.0) per decade | 1965 to 2025 | 46 | Not clearly different from zero |
| Mean daily maximum | 0.1 C (-0.3 to 0.4) per decade | 0.1 F (-0.5 to 0.7) per decade | 1965 to 2025 | 46 | Not clearly different from zero |
| Mean daily minimum | 0.4 C (0.1 to 0.8) per decade | 0.8 F (0.1 to 1.4) per decade | 1965 to 2025 | 46 | 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
1963 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 37.8 C (100.0 F) | 2007 | 33.3 C (91.9 F) | 64 |
| Coldest night (TNn) | -43.3 C (-45.9 F) | 1978 | -33.9 C (-29.0 F) | 64 |
| Wettest day (Rx1day) | 46.2 mm (1.8 in) | 1982 | 19.1 mm (0.8 in) | 64 |
| Wettest five days (Rx5day) | 82.1 mm (3.2 in) | 1982 | 29.3 mm (1.2 in) | 64 |
| Longest dry spell (CDD) | 89 days | 1976 | 47 days | 64 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1963 | 35.0 C (95.0 F) |
| 1964 | 33.9 C (93.0 F) |
| 1965 | 31.7 C (89.1 F) |
| 1966 | 33.9 C (93.0 F) |
| 1967 | 32.2 C (90.0 F) |
| 1968 | 32.8 C (91.0 F) |
| 1969 | 33.3 C (91.9 F) |
| 1970 | 33.3 C (91.9 F) |
| 1971 | 33.3 C (91.9 F) |
| 1972 | 34.4 C (93.9 F) |
| 1973 | 33.3 C (91.9 F) |
| 1974 | 33.3 C (91.9 F) |
| 1975 | 24.4 C (75.9 F) |
| 1976 | 33.3 C (91.9 F) |
| 1977 | 32.8 C (91.0 F) |
| 1978 | 33.9 C (93.0 F) |
| 1979 | 35.0 C (95.0 F) |
| 1980 | 32.8 C (91.0 F) |
| 1981 | 32.8 C (91.0 F) |
| 1982 | 34.4 C (93.9 F) |
| 1983 | 34.4 C (93.9 F) |
| 1984 | 33.3 C (91.9 F) |
| 1985 | 33.3 C (91.9 F) |
| 1986 | 33.3 C (91.9 F) |
| 1987 | 32.2 C (90.0 F) |
| 1988 | 34.4 C (93.9 F) |
| 1989 | 35.0 C (95.0 F) |
| 1990 | 34.4 C (93.9 F) |
| 1991 | 31.7 C (89.1 F) |
| 1992 | 32.2 C (90.0 F) |
| 1993 | 28.9 C (84.0 F) |
| 1994 | 33.3 C (91.9 F) |
| 1995 | 32.8 C (91.0 F) |
| 1996 | 31.7 C (89.1 F) |
| 1997 | 29.4 C (84.9 F) |
| 1998 | 31.7 C (89.1 F) |
| 1999 | 27.2 C (81.0 F) |
| 2000 | 32.8 C (91.0 F) |
| 2001 | 33.3 C (91.9 F) |
| 2002 | 32.2 C (90.0 F) |
| 2003 | 32.8 C (91.0 F) |
| 2004 | 31.7 C (89.1 F) |
| 2005 | 34.4 C (93.9 F) |
| 2006 | 34.4 C (93.9 F) |
| 2007 | 37.8 C (100.0 F) |
| 2008 | 32.8 C (91.0 F) |
| 2009 | 33.3 C (91.9 F) |
| 2010 | 29.4 C (84.9 F) |
| 2011 | 32.2 C (90.0 F) |
| 2012 | 33.3 C (91.9 F) |
| 2013 | 33.9 C (93.0 F) |
| 2014 | 33.3 C (91.9 F) |
| 2015 | 33.9 C (93.0 F) |
| 2016 | 32.2 C (90.0 F) |
| 2017 | 32.8 C (91.0 F) |
| 2018 | 35.6 C (96.1 F) |
| 2019 | 32.8 C (91.0 F) |
| 2020 | 34.4 C (93.9 F) |
| 2021 | 35.0 C (95.0 F) |
| 2022 | 34.4 C (93.9 F) |
| 2023 | 33.3 C (91.9 F) |
| 2024 | 34.4 C (93.9 F) |
| 2025 | 33.3 C (91.9 F) |
| 2026 | 36.1 C (97.0 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1963 | -32.2 C (-26.0 F) |
| 1964 | -31.7 C (-25.1 F) |
| 1965 | -28.3 C (-18.9 F) |
| 1966 | -32.8 C (-27.0 F) |
| 1967 | -32.8 C (-27.0 F) |
| 1968 | -35.0 C (-31.0 F) |
| 1969 | -33.9 C (-29.0 F) |
| 1970 | -35.0 C (-31.0 F) |
| 1971 | -40.0 C (-40.0 F) |
| 1972 | -39.4 C (-38.9 F) |
| 1973 | -37.2 C (-35.0 F) |
| 1974 | -40.0 C (-40.0 F) |
| 1975 | -36.1 C (-33.0 F) |
| 1976 | -33.9 C (-29.0 F) |
| 1977 | -38.9 C (-38.0 F) |
| 1978 | -43.3 C (-45.9 F) |
| 1979 | -41.7 C (-43.1 F) |
| 1980 | -39.4 C (-38.9 F) |
| 1981 | -27.2 C (-17.0 F) |
| 1982 | -40.0 C (-40.0 F) |
| 1983 | -40.6 C (-41.1 F) |
| 1984 | -41.7 C (-43.1 F) |
| 1985 | -43.3 C (-45.9 F) |
| 1986 | -32.2 C (-26.0 F) |
| 1987 | -37.2 C (-35.0 F) |
| 1988 | -33.3 C (-27.9 F) |
| 1989 | -41.7 C (-43.1 F) |
| 1990 | -42.8 C (-45.0 F) |
| 1991 | -28.9 C (-20.0 F) |
| 1992 | -34.4 C (-29.9 F) |
| 1993 | -37.2 C (-35.0 F) |
| 1994 | -30.0 C (-22.0 F) |
| 1995 | -30.6 C (-23.1 F) |
| 1996 | -31.1 C (-24.0 F) |
| 1997 | -36.1 C (-33.0 F) |
| 1998 | -37.2 C (-35.0 F) |
| 1999 | -29.4 C (-20.9 F) |
| 2000 | -31.1 C (-24.0 F) |
| 2001 | -35.0 C (-31.0 F) |
| 2002 | -37.8 C (-36.0 F) |
| 2003 | -37.2 C (-35.0 F) |
| 2004 | -35.0 C (-31.0 F) |
| 2005 | -38.3 C (-36.9 F) |
| 2006 | -33.3 C (-27.9 F) |
| 2007 | -33.3 C (-27.9 F) |
| 2008 | -33.9 C (-29.0 F) |
| 2009 | -32.8 C (-27.0 F) |
| 2010 | -34.4 C (-29.9 F) |
| 2011 | -32.2 C (-26.0 F) |
| 2012 | -28.9 C (-20.0 F) |
| 2013 | -33.9 C (-29.0 F) |
| 2014 | -34.4 C (-29.9 F) |
| 2015 | -31.7 C (-25.1 F) |
| 2016 | -33.3 C (-27.9 F) |
| 2017 | -38.3 C (-36.9 F) |
| 2018 | -31.7 C (-25.1 F) |
| 2019 | -33.9 C (-29.0 F) |
| 2020 | -31.7 C (-25.1 F) |
| 2021 | -23.3 C (-9.9 F) |
| 2022 | -30.6 C (-23.1 F) |
| 2023 | -40.0 C (-40.0 F) |
| 2024 | -32.8 C (-27.0 F) |
| 2025 | -25.6 C (-14.1 F) |
| 2026 | -21.1 C (-6.0 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1963 | 14.7 mm (0.6 in) |
| 1964 | 13.7 mm (0.5 in) |
| 1965 | 21.3 mm (0.8 in) |
| 1966 | 17.8 mm (0.7 in) |
| 1967 | 29.5 mm (1.2 in) |
| 1968 | 17.5 mm (0.7 in) |
| 1969 | 20.3 mm (0.8 in) |
| 1970 | 19.1 mm (0.8 in) |
| 1971 | 19.3 mm (0.8 in) |
| 1972 | 19.3 mm (0.8 in) |
| 1973 | 38.1 mm (1.5 in) |
| 1974 | 15.0 mm (0.6 in) |
| 1975 | 12.2 mm (0.5 in) |
| 1976 | 19.3 mm (0.8 in) |
| 1977 | 27.4 mm (1.1 in) |
| 1978 | 23.1 mm (0.9 in) |
| 1979 | 10.7 mm (0.4 in) |
| 1980 | 16.8 mm (0.7 in) |
| 1981 | 13.5 mm (0.5 in) |
| 1982 | 46.2 mm (1.8 in) |
| 1983 | 36.1 mm (1.4 in) |
| 1984 | 17.0 mm (0.7 in) |
| 1985 | 15.7 mm (0.6 in) |
| 1986 | 24.9 mm (1.0 in) |
| 1987 | 18.3 mm (0.7 in) |
| 1988 | 18.5 mm (0.7 in) |
| 1989 | 10.7 mm (0.4 in) |
| 1990 | 20.3 mm (0.8 in) |
| 1991 | 27.2 mm (1.1 in) |
| 1992 | 26.4 mm (1.0 in) |
| 1993 | 13.7 mm (0.5 in) |
| 1994 | 9.7 mm (0.38 in) |
| 1995 | 19.1 mm (0.8 in) |
| 1996 | 14.0 mm (0.6 in) |
| 1997 | 18.5 mm (0.7 in) |
| 1998 | 27.4 mm (1.1 in) |
| 1999 | 19.6 mm (0.8 in) |
| 2000 | 14.0 mm (0.6 in) |
| 2001 | 13.0 mm (0.5 in) |
| 2002 | 25.9 mm (1.0 in) |
| 2003 | 18.3 mm (0.7 in) |
| 2004 | 26.4 mm (1.0 in) |
| 2005 | 19.8 mm (0.8 in) |
| 2006 | 15.7 mm (0.6 in) |
| 2007 | 14.5 mm (0.6 in) |
| 2008 | 8.1 mm (0.32 in) |
| 2009 | 10.9 mm (0.4 in) |
| 2010 | 21.1 mm (0.8 in) |
| 2011 | 37.1 mm (1.5 in) |
| 2012 | 10.2 mm (0.4 in) |
| 2013 | 25.9 mm (1.0 in) |
| 2014 | 22.9 mm (0.9 in) |
| 2015 | 24.6 mm (1.0 in) |
| 2016 | 36.6 mm (1.4 in) |
| 2017 | 25.4 mm (1.0 in) |
| 2018 | 35.6 mm (1.4 in) |
| 2019 | 16.5 mm (0.6 in) |
| 2020 | 13.5 mm (0.5 in) |
| 2021 | 22.9 mm (0.9 in) |
| 2022 | 14.0 mm (0.6 in) |
| 2023 | 22.9 mm (0.9 in) |
| 2024 | 22.9 mm (0.9 in) |
| 2025 | 10.2 mm (0.4 in) |
| 2026 | 12.2 mm (0.5 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1963 | 28.9 mm (1.1 in) |
| 1964 | 20.5 mm (0.8 in) |
| 1965 | 42.2 mm (1.7 in) |
| 1966 | 18.3 mm (0.7 in) |
| 1967 | 35.6 mm (1.4 in) |
| 1968 | 33.4 mm (1.3 in) |
| 1969 | 30.0 mm (1.2 in) |
| 1970 | 39.7 mm (1.6 in) |
| 1971 | 33.0 mm (1.3 in) |
| 1972 | 28.2 mm (1.1 in) |
| 1973 | 58.0 mm (2.3 in) |
| 1974 | 16.6 mm (0.7 in) |
| 1975 | 22.1 mm (0.9 in) |
| 1976 | 26.7 mm (1.1 in) |
| 1977 | 28.4 mm (1.1 in) |
| 1978 | 43.2 mm (1.7 in) |
| 1979 | 23.7 mm (0.9 in) |
| 1980 | 40.9 mm (1.6 in) |
| 1981 | 27.2 mm (1.1 in) |
| 1982 | 82.1 mm (3.2 in) |
| 1983 | 43.7 mm (1.7 in) |
| 1984 | 30.0 mm (1.2 in) |
| 1985 | 17.3 mm (0.7 in) |
| 1986 | 45.0 mm (1.8 in) |
| 1987 | 45.5 mm (1.8 in) |
| 1988 | 26.4 mm (1.0 in) |
| 1989 | 18.6 mm (0.7 in) |
| 1990 | 29.7 mm (1.2 in) |
| 1991 | 43.2 mm (1.7 in) |
| 1992 | 26.9 mm (1.1 in) |
| 1993 | 24.7 mm (1.0 in) |
| 1994 | 21.1 mm (0.8 in) |
| 1995 | 27.2 mm (1.1 in) |
| 1996 | 24.3 mm (1.0 in) |
| 1997 | 30.7 mm (1.2 in) |
| 1998 | 39.5 mm (1.6 in) |
| 1999 | 34.2 mm (1.3 in) |
| 2000 | 21.6 mm (0.9 in) |
| 2001 | 16.8 mm (0.7 in) |
| 2002 | 28.7 mm (1.1 in) |
| 2003 | 38.8 mm (1.5 in) |
| 2004 | 46.4 mm (1.8 in) |
| 2005 | 39.9 mm (1.6 in) |
| 2006 | 19.0 mm (0.7 in) |
| 2007 | 26.0 mm (1.0 in) |
| 2008 | 15.2 mm (0.6 in) |
| 2009 | 13.5 mm (0.5 in) |
| 2010 | 30.6 mm (1.2 in) |
| 2011 | 41.2 mm (1.6 in) |
| 2012 | 15.5 mm (0.6 in) |
| 2013 | 81.2 mm (3.2 in) |
| 2014 | 44.5 mm (1.8 in) |
| 2015 | 51.1 mm (2.0 in) |
| 2016 | 72.1 mm (2.8 in) |
| 2017 | 43.7 mm (1.7 in) |
| 2018 | 40.6 mm (1.6 in) |
| 2019 | 20.6 mm (0.8 in) |
| 2020 | 18.5 mm (0.7 in) |
| 2021 | 43.7 mm (1.7 in) |
| 2022 | 16.8 mm (0.7 in) |
| 2023 | 37.3 mm (1.5 in) |
| 2024 | 24.2 mm (1.0 in) |
| 2025 | 16.8 mm (0.7 in) |
| 2026 | 16.0 mm (0.6 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1963 | 31 days |
| 1964 | 84 days |
| 1965 | 36 days |
| 1966 | 34 days |
| 1967 | 43 days |
| 1968 | 48 days |
| 1969 | 51 days |
| 1970 | 47 days |
| 1971 | 61 days |
| 1972 | 80 days |
| 1973 | 55 days |
| 1974 | 57 days |
| 1975 | 32 days |
| 1976 | 89 days |
| 1977 | 75 days |
| 1978 | 54 days |
| 1979 | 35 days |
| 1980 | 29 days |
| 1981 | 40 days |
| 1982 | 38 days |
| 1983 | 29 days |
| 1984 | 43 days |
| 1985 | 57 days |
| 1986 | 49 days |
| 1987 | 38 days |
| 1988 | 55 days |
| 1989 | 37 days |
| 1990 | 48 days |
| 1991 | 55 days |
| 1992 | 61 days |
| 1993 | 32 days |
| 1994 | 40 days |
| 1995 | 27 days |
| 1996 | 28 days |
| 1997 | 31 days |
| 1998 | 54 days |
| 1999 | 61 days |
| 2000 | 36 days |
| 2001 | 42 days |
| 2002 | 58 days |
| 2003 | 58 days |
| 2004 | 33 days |
| 2005 | 53 days |
| 2006 | 46 days |
| 2007 | 65 days |
| 2008 | 46 days |
| 2009 | 47 days |
| 2010 | 36 days |
| 2011 | 50 days |
| 2012 | 48 days |
| 2013 | 38 days |
| 2014 | 23 days |
| 2015 | 63 days |
| 2016 | 31 days |
| 2017 | 43 days |
| 2018 | 71 days |
| 2019 | 36 days |
| 2020 | 61 days |
| 2021 | 32 days |
| 2022 | 52 days |
| 2023 | 49 days |
| 2024 | 59 days |
| 2025 | 30 days |
| 2026 | 34 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
46 years with a frostAcross 46 years with a frost, the median last spring frost at Fontenelle Dam falls on 20 June and the median first autumn frost on 29 August, which leaves a median of 69 days between them.
Fitted over all years, the growing season changes by +4.7 days per decade at this station.
| Measure | Median, all years | Earliest period | Recent period (1988 to 2025) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 20 June | n/a | 19 June | n/a | -1.8 days per decade |
| First autumn frost | 29 August | n/a | 29 August | n/a | +2.9 days per decade |
| Growing days | 69 days | n/a | 79 days | n/a | +4.7 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
56 years, 1964 to 2025A day with at least 19.3 mm (0.8 in) of rain is expected about once in 2 years. A day with at least 47.0 mm (1.9 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 19.3 mm (0.8 in) | |
| 5 years | 26.7 mm (1.1 in) | |
| 10 years | 31.6 mm (1.2 in) | |
| 25 years | 37.8 mm (1.5 in) | |
| 50 years | 42.4 mm (1.7 in) | |
| 100 years | 47.0 mm (1.9 in) | Longer than the 56 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, 56 years of values from 1964 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: 46.2 mm (1.8 in) in 1982; 38.1 mm (1.5 in) in 1973; 37.1 mm (1.5 in) in 2011.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Climate Twins
2006 to 2025 against 1961 to 1990Over 2006 to 2025, Fontenelle Dam had a mean temperature of 4.8 C (40.7 F) and 186.4 mm (7.3 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Wamsutter (United States, 176 km away), Mackay Lost Rvr Rs (United States, 360 km away) and Idaho Falls 46 W (United States, 291 km away).
| Twin station | Country | Distance away | Mean temperature, 1961-1990 | Rain a year, 1961-1990 | Climate difference |
|---|---|---|---|---|---|
| Wamsutter | United States | 176 km (109 mi) | 5.1 C (41.2 F) | 163.9 mm (6.5 in) | 0.63 |
| Mackay Lost Rvr Rs | United States | 360 km (224 mi) | 5.1 C (41.1 F) | 251.0 mm (9.9 in) | 0.74 |
| Idaho Falls 46 W | United States | 291 km (181 mi) | 5.5 C (41.9 F) | 232.8 mm (9.2 in) | 0.92 |
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 2026-10-12 (12 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-13).