Flattop Mtn. Weather Records (USS0013A19S)
Record envelope, standing records and threshold days for Flattop Mtn. (USS0013A19S), Montana, United States, with 49 years of record.
Key Facts for Flattop Mtn.
- Flattop Mtn. (USS0013A19S) is a weather station in Montana, United States at 48.80 latitude and -113.86 longitude, 1,920 m (6,300 ft) above sea level.
- The station reports from 1978 to 2026, 49 years of record.
- 1,464 records set at Flattop Mtn. still stand.
- Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
- Flattop Mtn. tied a daily record precipitation of 22.9 mm (0.9 in) on 8 September 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, 48.80 latitude, -113.86 longitude.
- Elevation: 1,920 m (6,300 ft).
- Period of record: 1978 to 2026, 49 years.
- Eligible elements: tmax, tmin, prcp.
Daily Record Envelope and 2026
4 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 10.4 C (50.7 F) | -41.9 C (-43.4 F) | 2.3 C (36.1 F) | -22.3 C (-8.1 F) |
| Feb | 12.0 C (53.6 F) | -41.2 C (-42.2 F) | 6.7 C (44.1 F) | -24.1 C (-11.4 F) |
| Mar | 15.8 C (60.4 F) | -34.0 C (-29.2 F) | 7.0 C (44.6 F) | -20.3 C (-4.5 F) |
| Apr | 24.4 C (75.9 F) | -25.3 C (-13.5 F) | 16.3 C (61.3 F) | -13.1 C (8.4 F) |
| May | 28.7 C (83.7 F) | -15.2 C (4.6 F) | 20.8 C (69.4 F) | -8.0 C (17.6 F) |
| Jun | 31.5 C (88.7 F) | -9.9 C (14.2 F) | 19.1 C (66.4 F) | -1.6 C (29.1 F) |
| Jul | 31.1 C (88.0 F) | -11.0 C (12.2 F) | 26.0 C (78.8 F) | 2.3 C (36.1 F) |
| Aug | 32.3 C (90.1 F) | -10.4 C (13.3 F) | 26.0 C (78.8 F) | 1.1 C (34.0 F) |
| Sep | 29.2 C (84.6 F) | -14.8 C (5.4 F) | 22.0 C (71.6 F) | -4.5 C (23.9 F) |
| Oct | 24.5 C (76.1 F) | -25.3 C (-13.5 F) | 16.3 C (61.3 F) | -10.7 C (12.7 F) |
| Nov | 14.8 C (58.6 F) | -33.3 C (-27.9 F) | n/a | n/a |
| Dec | 6.2 C (43.2 F) | -39.0 C (-38.2 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1982 | 28 |
| 1983 | 83 |
| 1984 | 30 |
| 1985 | 50 |
| 1986 | 47 |
| 1987 | 35 |
| 1988 | 44 |
| 1989 | 32 |
| 1990 | 29 |
| 1991 | 22 |
| 1992 | 46 |
| 1993 | 27 |
| 1994 | 21 |
| 1995 | 32 |
| 1996 | 68 |
| 1997 | 32 |
| 1998 | 18 |
| 1999 | 33 |
| 2000 | 28 |
| 2001 | 23 |
| 2002 | 42 |
| 2003 | 28 |
| 2004 | 24 |
| 2005 | 37 |
| 2006 | 25 |
| 2007 | 22 |
| 2008 | 34 |
| 2009 | 32 |
| 2010 | 21 |
| 2011 | 21 |
| 2012 | 29 |
| 2013 | 32 |
| 2014 | 40 |
| 2015 | 29 |
| 2016 | 18 |
| 2017 | 11 |
| 2018 | 22 |
| 2019 | 33 |
| 2020 | 30 |
| 2021 | 44 |
| 2022 | 36 |
| 2023 | 43 |
| 2024 | 44 |
| 2025 | 22 |
| 2026 | 17 |
All-Time Record Progression
3 new records| Date | Kind | Detail |
|---|---|---|
| 2018-08-10 | Record high maximum temperature | Record high maximum temperature 32.3 C (90.1 F) |
| 2024-01-12 | Record low minimum temperature | Record low minimum temperature -41.5 C (-42.7 F) |
| 2024-01-13 | Record low minimum temperature | Record low minimum temperature -41.9 C (-43.4 F) |
Wettest Day of Each Month
Feb: 144.8 mm (5.7 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 66.0 mm (2.6 in) | 7 January 2022 |
| Feb | 144.8 mm (5.7 in) | 23 February 1986 |
| Mar | 66.0 mm (2.6 in) | 19 March 1990 |
| Apr | 61.0 mm (2.4 in) | 22 April 1986 |
| May | 76.2 mm (3.0 in) | 22 May 2016 |
| Jun | 109.2 mm (4.3 in) | 6 June 1995 |
| Jul | 58.4 mm (2.3 in) | 26 July 1990 |
| Aug | 71.1 mm (2.8 in) | 30 August 2023 |
| Sep | 94.0 mm (3.7 in) | 29 September 2005 |
| Oct | 71.1 mm (2.8 in) | 8 October 1999 |
| Nov | 116.8 mm (4.6 in) | 6 November 2006 |
| Dec | 88.9 mm (3.5 in) | 10 December 2025 |
Period of Record Coverage
1982 to 2026| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1982 | 103 | 28% | No |
| 1983 | 146 | 40% | No |
| 1984 | 274 | 75% | No |
| 1985 | 358 | 98% | Yes |
| 1986 | 358 | 98% | Yes |
| 1987 | 288 | 79% | No |
| 1988 | 207 | 57% | No |
| 1989 | 360 | 99% | Yes |
| 1990 | 359 | 98% | Yes |
| 1991 | 360 | 99% | Yes |
| 1992 | 364 | 99% | Yes |
| 1993 | 340 | 93% | Yes |
| 1994 | 350 | 96% | Yes |
| 1995 | 364 | 100% | Yes |
| 1996 | 366 | 100% | Yes |
| 1997 | 364 | 100% | Yes |
| 1998 | 364 | 100% | Yes |
| 1999 | 365 | 100% | Yes |
| 2000 | 366 | 100% | Yes |
| 2001 | 365 | 100% | Yes |
| 2002 | 364 | 100% | Yes |
| 2003 | 365 | 100% | Yes |
| 2004 | 366 | 100% | Yes |
| 2005 | 365 | 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 | 365 | 100% | Yes |
| 2013 | 365 | 100% | Yes |
| 2014 | 365 | 100% | Yes |
| 2015 | 365 | 100% | Yes |
| 2016 | 273 | 75% | No |
| 2017 | 95 | 26% | No |
| 2018 | 365 | 100% | Yes |
| 2019 | 365 | 100% | Yes |
| 2020 | 366 | 100% | Yes |
| 2021 | 364 | 100% | Yes |
| 2022 | 363 | 99% | Yes |
| 2023 | 364 | 100% | Yes |
| 2024 | 364 | 99% | Yes |
| 2025 | 342 | 94% | Yes |
| 2026 | 269 | 74% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 8 September 2026 | Flattop Mtn., US | daily rain (Tie, Provisional) | 22.9 mm (0.9 in) | tie | 23 years | 2 of 100 (Routine) |
| 7 September 2026 | Flattop Mtn., US | daily rain (Provisional) | 48.3 mm (1.9 in) | 35.6 mm (1.4 in) | 9 years | 45 of 100 (Notable) |
| 2 September 2026 | Flattop Mtn., US | daily rain (Provisional) | 25.4 mm (1.0 in) | 2.5 mm (0.10 in) | 25 years | 13 of 100 (Routine) |
| 30 August 2026 | Flattop Mtn., US | daily low max (Provisional) | 6.0 C (42.8 F) | 1.4 C (2.5 F) | 32 years | 15 of 100 (Routine) |
| 23 August 2026 | Flattop Mtn., US | daily high min (Provisional) | 8.9 C (48.0 F) | 0.4 C (0.7 F) | 15 years | 9 of 100 (Routine) |
| 22 August 2026 | Flattop Mtn., US | daily high max (Provisional) | 25.7 C (78.3 F) | 0.1 C (0.2 F) | 20 years | 10 of 100 (Routine) |
| 4 August 2026 | Flattop Mtn., US | daily low min | 1.1 C (34.0 F) | 0.5 C (0.9 F) | 32 years | 14 of 100 (Routine) |
| 26 July 2026 | Flattop Mtn., US | daily high min | 10.9 C (51.6 F) | 0.4 C (0.7 F) | 4 years | 6 of 100 (Routine) |
| 24 July 2026 | Flattop Mtn., US | daily high min | 14.4 C (57.9 F) | 3.3 C (5.9 F) | 3 years | 14 of 100 (Routine) |
| 17 July 2026 | Flattop Mtn., US | daily high min | 11.8 C (53.2 F) | 1.2 C (2.2 F) | 1 year | 7 of 100 (Routine) |
| 7 July 2026 | Flattop Mtn., US | daily high min | 9.2 C (48.6 F) | 0.4 C (0.7 F) | 4 years | 6 of 100 (Routine) |
| 29 June 2026 | Flattop Mtn., US | daily rain | 50.8 mm (2.0 in) | 22.9 mm (0.9 in) | 28 years | 32 of 100 (Routine) |
| 28 June 2026 | Flattop Mtn., US | daily rain | 61.0 mm (2.4 in) | 45.8 mm (1.8 in) | 12 years | 47 of 100 (Notable) |
| 1 June 2026 | Flattop Mtn., US | daily rain (Tie) | 27.9 mm (1.1 in) | tie | 36 years | 3 of 100 (Routine) |
| 28 May 2026 | Flattop Mtn., US | daily high min (Tie) | 4.7 C (40.5 F) | tie | 40 years | 4 of 100 (Routine) |
| 26 May 2026 | Flattop Mtn., US | daily high min | 3.5 C (38.3 F) | 0.1 C (0.2 F) | 3 years | 4 of 100 (Routine) |
| 13 May 2026 | Flattop Mtn., US | daily rain | 30.5 mm (1.2 in) | 7.6 mm (0.30 in) | 40 years | 25 of 100 (Routine) |
| 25 April 2026 | Flattop Mtn., US | daily low min | -13.1 C (8.4 F) | 0.9 C (1.6 F) | 41 years | 17 of 100 (Routine) |
| 25 April 2026 | Flattop Mtn., US | daily low max | -1.1 C (30.0 F) | 0.2 C (0.4 F) | 40 years | 16 of 100 (Routine) |
| 24 April 2026 | Flattop Mtn., US | daily low max | -3.6 C (25.5 F) | 2.1 C (3.8 F) | 40 years | 19 of 100 (Routine) |
Climate Trend
34 complete years, 1985 to 2024| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1985 | -1.8 C | -2.56 C |
| 1986 | 0.9 C | +0.20 C |
| 1989 | -0.5 C | -1.27 C |
| 1990 | -0.1 C | -0.84 C |
| 1991 | 0.5 C | -0.18 C |
| 1992 | 1.1 C | +0.36 C |
| 1994 | 1.0 C | +0.32 C |
| 1995 | 0.1 C | -0.58 C |
| 1996 | -1.0 C | -1.74 C |
| 1997 | 0.4 C | -0.32 C |
| 1998 | 1.5 C | +0.82 C |
| 1999 | 0.7 C | -0.02 C |
| 2000 | 0.2 C | -0.52 C |
| 2001 | 0.7 C | 0.00 C |
| 2002 | -0.3 C | -1.06 C |
| 2003 | 1.2 C | +0.47 C |
| 2004 | 1.0 C | +0.32 C |
| 2005 | 0.7 C | -0.01 C |
| 2006 | 1.8 C | +1.04 C |
| 2007 | 1.5 C | +0.77 C |
| 2008 | 0.6 C | -0.17 C |
| 2009 | 0.4 C | -0.33 C |
| 2010 | 1.2 C | +0.45 C |
| 2011 | 0.5 C | -0.23 C |
| 2012 | 1.7 C | +0.99 C |
| 2013 | 1.2 C | +0.50 C |
| 2014 | 0.7 C | 0.00 C |
| 2018 | 1.2 C | +0.47 C |
| 2019 | 0.0 C | -0.68 C |
| 2020 | 1.2 C | +0.49 C |
| 2021 | 1.5 C | +0.76 C |
| 2022 | 0.8 C | +0.03 C |
| 2023 | 1.9 C | +1.19 C |
| 2024 | 2.1 C | +1.33 C |
The annual mean temperature here has risen by 0.4 C (0.2 to 0.6) per decade over 1985 to 2024. In Fahrenheit: 0.7 F (0.3 to 1.1) per decade. The slope is a straight line fitted to 34 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.4 C (0.2 to 0.6) per decade | 0.7 F (0.3 to 1.1) per decade | 1985 to 2024 | 34 | Rise |
| Mean daily maximum | 0.4 C (0.2 to 0.7) per decade | 0.8 F (0.4 to 1.2) per decade | 1985 to 2024 | 34 | Rise |
| Mean daily minimum | 0.4 C (0.2 to 0.6) per decade | 0.7 F (0.3 to 1.1) per decade | 1985 to 2024 | 34 | 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
1978 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 32.3 C (90.1 F) | 2018 | 28.3 C (82.9 F) | 45 |
| Coldest night (TNn) | -41.9 C (-43.4 F) | 2024 | -31.3 C (-24.3 F) | 45 |
| Wettest day (Rx1day) | 144.8 mm (5.7 in) | 1986 | 58.4 mm (2.3 in) | 49 |
| Wettest five days (Rx5day) | 274.3 mm (10.8 in) | 2006 | 127.0 mm (5.0 in) | 49 |
| Longest dry spell (CDD) | 51 days | 1984 | 18 days | 49 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1978 | n/a |
| 1979 | n/a |
| 1980 | n/a |
| 1981 | n/a |
| 1982 | 28.8 C (83.8 F) |
| 1983 | 29.5 C (85.1 F) |
| 1984 | 30.5 C (86.9 F) |
| 1985 | 27.0 C (80.6 F) |
| 1986 | 28.7 C (83.7 F) |
| 1987 | 28.6 C (83.5 F) |
| 1988 | 29.2 C (84.6 F) |
| 1989 | 27.0 C (80.6 F) |
| 1990 | 27.8 C (82.0 F) |
| 1991 | 27.8 C (82.0 F) |
| 1992 | 26.2 C (79.2 F) |
| 1993 | 24.6 C (76.3 F) |
| 1994 | 29.2 C (84.6 F) |
| 1995 | 24.4 C (75.9 F) |
| 1996 | 26.6 C (79.9 F) |
| 1997 | 28.2 C (82.8 F) |
| 1998 | 27.9 C (82.2 F) |
| 1999 | 26.5 C (79.7 F) |
| 2000 | 28.3 C (82.9 F) |
| 2001 | 27.8 C (82.0 F) |
| 2002 | 31.1 C (88.0 F) |
| 2003 | 28.8 C (83.8 F) |
| 2004 | 27.6 C (81.7 F) |
| 2005 | 27.1 C (80.8 F) |
| 2006 | 30.9 C (87.6 F) |
| 2007 | 30.5 C (86.9 F) |
| 2008 | 30.5 C (86.9 F) |
| 2009 | 27.4 C (81.3 F) |
| 2010 | 25.7 C (78.3 F) |
| 2011 | 27.2 C (81.0 F) |
| 2012 | 28.9 C (84.0 F) |
| 2013 | 28.9 C (84.0 F) |
| 2014 | 27.1 C (80.8 F) |
| 2015 | 31.0 C (87.8 F) |
| 2016 | 25.3 C (77.5 F) |
| 2017 | 17.5 C (63.5 F) |
| 2018 | 32.3 C (90.1 F) |
| 2019 | 28.7 C (83.7 F) |
| 2020 | 29.8 C (85.6 F) |
| 2021 | 31.5 C (88.7 F) |
| 2022 | 28.9 C (84.0 F) |
| 2023 | 29.2 C (84.6 F) |
| 2024 | 28.9 C (84.0 F) |
| 2025 | 26.5 C (79.7 F) |
| 2026 | 26.0 C (78.8 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1978 | n/a |
| 1979 | n/a |
| 1980 | n/a |
| 1981 | n/a |
| 1982 | -23.0 C (-9.4 F) |
| 1983 | -37.6 C (-35.7 F) |
| 1984 | -30.2 C (-22.4 F) |
| 1985 | -34.0 C (-29.2 F) |
| 1986 | -29.8 C (-21.6 F) |
| 1987 | -26.7 C (-16.1 F) |
| 1988 | -25.0 C (-13.0 F) |
| 1989 | -41.2 C (-42.2 F) |
| 1990 | -39.0 C (-38.2 F) |
| 1991 | -28.5 C (-19.3 F) |
| 1992 | -33.1 C (-27.6 F) |
| 1993 | -33.3 C (-27.9 F) |
| 1994 | -33.2 C (-27.8 F) |
| 1995 | -33.0 C (-27.4 F) |
| 1996 | -33.8 C (-28.8 F) |
| 1997 | -29.6 C (-21.3 F) |
| 1998 | -35.7 C (-32.3 F) |
| 1999 | -28.1 C (-18.6 F) |
| 2000 | -28.0 C (-18.4 F) |
| 2001 | -26.0 C (-14.8 F) |
| 2002 | -30.6 C (-23.1 F) |
| 2003 | -30.6 C (-23.1 F) |
| 2004 | -34.6 C (-30.3 F) |
| 2005 | -29.9 C (-21.8 F) |
| 2006 | -34.1 C (-29.4 F) |
| 2007 | -30.1 C (-22.2 F) |
| 2008 | -33.7 C (-28.7 F) |
| 2009 | -31.3 C (-24.3 F) |
| 2010 | -31.9 C (-25.4 F) |
| 2011 | -32.8 C (-27.0 F) |
| 2012 | -22.7 C (-8.9 F) |
| 2013 | -35.1 C (-31.2 F) |
| 2014 | -32.0 C (-25.6 F) |
| 2015 | -22.8 C (-9.0 F) |
| 2016 | -17.8 C (0.0 F) |
| 2017 | -28.5 C (-19.3 F) |
| 2018 | -29.2 C (-20.6 F) |
| 2019 | -32.8 C (-27.0 F) |
| 2020 | -26.2 C (-15.2 F) |
| 2021 | -34.2 C (-29.6 F) |
| 2022 | -37.1 C (-34.8 F) |
| 2023 | -34.3 C (-29.7 F) |
| 2024 | -41.9 C (-43.4 F) |
| 2025 | -29.1 C (-20.4 F) |
| 2026 | -24.1 C (-11.4 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1978 | 76.2 mm (3.0 in) |
| 1979 | 43.2 mm (1.7 in) |
| 1980 | 58.4 mm (2.3 in) |
| 1981 | 61.0 mm (2.4 in) |
| 1982 | 58.4 mm (2.3 in) |
| 1983 | 43.2 mm (1.7 in) |
| 1984 | 55.9 mm (2.2 in) |
| 1985 | 45.7 mm (1.8 in) |
| 1986 | 144.8 mm (5.7 in) |
| 1987 | 55.9 mm (2.2 in) |
| 1988 | 35.6 mm (1.4 in) |
| 1989 | 55.9 mm (2.2 in) |
| 1990 | 66.0 mm (2.6 in) |
| 1991 | 61.0 mm (2.4 in) |
| 1992 | 43.2 mm (1.7 in) |
| 1993 | 63.5 mm (2.5 in) |
| 1994 | 55.9 mm (2.2 in) |
| 1995 | 109.2 mm (4.3 in) |
| 1996 | 53.3 mm (2.1 in) |
| 1997 | 35.6 mm (1.4 in) |
| 1998 | 55.9 mm (2.2 in) |
| 1999 | 71.1 mm (2.8 in) |
| 2000 | 50.8 mm (2.0 in) |
| 2001 | 43.2 mm (1.7 in) |
| 2002 | 66.0 mm (2.6 in) |
| 2003 | 63.5 mm (2.5 in) |
| 2004 | 48.3 mm (1.9 in) |
| 2005 | 94.0 mm (3.7 in) |
| 2006 | 116.8 mm (4.6 in) |
| 2007 | 50.8 mm (2.0 in) |
| 2008 | 45.7 mm (1.8 in) |
| 2009 | 63.5 mm (2.5 in) |
| 2010 | 50.8 mm (2.0 in) |
| 2011 | 55.9 mm (2.2 in) |
| 2012 | 58.4 mm (2.3 in) |
| 2013 | 53.3 mm (2.1 in) |
| 2014 | 78.7 mm (3.1 in) |
| 2015 | 55.9 mm (2.2 in) |
| 2016 | 76.2 mm (3.0 in) |
| 2017 | 61.0 mm (2.4 in) |
| 2018 | 63.5 mm (2.5 in) |
| 2019 | 61.0 mm (2.4 in) |
| 2020 | 48.3 mm (1.9 in) |
| 2021 | 68.6 mm (2.7 in) |
| 2022 | 66.0 mm (2.6 in) |
| 2023 | 71.1 mm (2.8 in) |
| 2024 | 45.7 mm (1.8 in) |
| 2025 | 88.9 mm (3.5 in) |
| 2026 | 61.0 mm (2.4 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1978 | 127.0 mm (5.0 in) |
| 1979 | 132.1 mm (5.2 in) |
| 1980 | 124.5 mm (4.9 in) |
| 1981 | 114.4 mm (4.5 in) |
| 1982 | 157.5 mm (6.2 in) |
| 1983 | 119.4 mm (4.7 in) |
| 1984 | 114.4 mm (4.5 in) |
| 1985 | 124.4 mm (4.9 in) |
| 1986 | 218.4 mm (8.6 in) |
| 1987 | 86.3 mm (3.4 in) |
| 1988 | 104.1 mm (4.1 in) |
| 1989 | 121.9 mm (4.8 in) |
| 1990 | 157.5 mm (6.2 in) |
| 1991 | 96.7 mm (3.8 in) |
| 1992 | 83.8 mm (3.3 in) |
| 1993 | 114.2 mm (4.5 in) |
| 1994 | 132.1 mm (5.2 in) |
| 1995 | 144.8 mm (5.7 in) |
| 1996 | 144.8 mm (5.7 in) |
| 1997 | 160.1 mm (6.3 in) |
| 1998 | 157.5 mm (6.2 in) |
| 1999 | 121.8 mm (4.8 in) |
| 2000 | 96.5 mm (3.8 in) |
| 2001 | 111.8 mm (4.4 in) |
| 2002 | 129.5 mm (5.1 in) |
| 2003 | 122.0 mm (4.8 in) |
| 2004 | 165.2 mm (6.5 in) |
| 2005 | 132.1 mm (5.2 in) |
| 2006 | 274.3 mm (10.8 in) |
| 2007 | 121.9 mm (4.8 in) |
| 2008 | 114.2 mm (4.5 in) |
| 2009 | 152.4 mm (6.0 in) |
| 2010 | 111.8 mm (4.4 in) |
| 2011 | 162.6 mm (6.4 in) |
| 2012 | 139.7 mm (5.5 in) |
| 2013 | 129.6 mm (5.1 in) |
| 2014 | 160.1 mm (6.3 in) |
| 2015 | 142.2 mm (5.6 in) |
| 2016 | 121.9 mm (4.8 in) |
| 2017 | 154.9 mm (6.1 in) |
| 2018 | 116.7 mm (4.6 in) |
| 2019 | 129.6 mm (5.1 in) |
| 2020 | 111.7 mm (4.4 in) |
| 2021 | 157.5 mm (6.2 in) |
| 2022 | 165.1 mm (6.5 in) |
| 2023 | 101.7 mm (4.0 in) |
| 2024 | 119.3 mm (4.7 in) |
| 2025 | 172.7 mm (6.8 in) |
| 2026 | 127.0 mm (5.0 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1978 | 12 days |
| 1979 | 36 days |
| 1980 | 9 days |
| 1981 | 23 days |
| 1982 | 15 days |
| 1983 | 15 days |
| 1984 | 51 days |
| 1985 | 36 days |
| 1986 | 34 days |
| 1987 | 26 days |
| 1988 | 16 days |
| 1989 | 11 days |
| 1990 | 14 days |
| 1991 | 24 days |
| 1992 | 13 days |
| 1993 | 14 days |
| 1994 | 25 days |
| 1995 | 19 days |
| 1996 | 20 days |
| 1997 | 9 days |
| 1998 | 38 days |
| 1999 | 18 days |
| 2000 | 19 days |
| 2001 | 14 days |
| 2002 | 14 days |
| 2003 | 18 days |
| 2004 | 10 days |
| 2005 | 19 days |
| 2006 | 15 days |
| 2007 | 31 days |
| 2008 | 17 days |
| 2009 | 19 days |
| 2010 | 10 days |
| 2011 | 20 days |
| 2012 | 12 days |
| 2013 | 20 days |
| 2014 | 15 days |
| 2015 | 16 days |
| 2016 | 17 days |
| 2017 | 29 days |
| 2018 | 29 days |
| 2019 | 21 days |
| 2020 | 24 days |
| 2021 | 18 days |
| 2022 | 18 days |
| 2023 | 26 days |
| 2024 | 19 days |
| 2025 | 23 days |
| 2026 | 12 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
34 years with a frostAcross 34 years with a frost, the median last spring frost at Flattop Mtn. falls on 22 June and the median first autumn frost on 10 August, which leaves a median of 43 days between them.
Fitted over all years, the growing season changes by +13.0 days per decade at this station.
| Measure | Median, all years | Earliest period | Recent period (1991 to 2024) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 22 June | n/a | 22 June | n/a | -1.8 days per decade |
| First autumn frost | 10 August | n/a | 19 August | n/a | +11.2 days per decade |
| Growing days | 43 days | n/a | 58 days | n/a | +13.0 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
47 years, 1979 to 2025A day with at least 56.9 mm (2.2 in) of rain is expected about once in 2 years. A day with at least 141.3 mm (5.6 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 56.9 mm (2.2 in) | |
| 5 years | 72.6 mm (2.9 in) | |
| 10 years | 85.4 mm (3.4 in) | |
| 25 years | 104.7 mm (4.1 in) | |
| 50 years | 121.7 mm (4.8 in) | Longer than the 47 years of record |
| 100 years | 141.3 mm (5.6 in) | Longer than the 47 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, 47 years of values from 1979 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: 144.8 mm (5.7 in) in 1986; 116.8 mm (4.6 in) in 2006; 109.2 mm (4.3 in) in 1995.
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).