Birch Hill Dam Weather Records (USC00190666)
Record envelope, standing records and threshold days for Birch Hill Dam (USC00190666), Massachusetts, United States, with 79 years of record.
Key Facts for Birch Hill Dam
- Birch Hill Dam (USC00190666) is a weather station in Massachusetts, United States at 42.63 latitude and -72.12 longitude, 261 m (855 ft) above sea level.
- The station reports from 1948 to 2026, 79 years of record.
- 1,464 records set at Birch Hill Dam still stand.
- Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
- Birch Hill Dam set a monthly record daily precipitation of 108.7 mm (4.3 in) on 30 July 2026.
About the Station
- Location: Massachusetts, United States, 42.63 latitude, -72.12 longitude.
- Elevation: 261 m (855 ft).
- Period of record: 1948 to 2026, 79 years.
- Eligible elements: tmax, tmin, prcp, snow, snwd.
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 | 18.9 C (66.0 F) | -36.7 C (-34.1 F) | n/a | n/a |
| Feb | 22.2 C (72.0 F) | -33.3 C (-27.9 F) | n/a | n/a |
| Mar | 27.8 C (82.0 F) | -28.3 C (-18.9 F) | n/a | n/a |
| Apr | 32.8 C (91.0 F) | -14.4 C (6.1 F) | n/a | n/a |
| May | 33.9 C (93.0 F) | -6.7 C (19.9 F) | n/a | n/a |
| Jun | 36.1 C (97.0 F) | -2.8 C (27.0 F) | n/a | n/a |
| Jul | 37.2 C (99.0 F) | 1.1 C (34.0 F) | n/a | n/a |
| Aug | 37.2 C (99.0 F) | -1.7 C (28.9 F) | n/a | n/a |
| Sep | 36.7 C (98.1 F) | -6.7 C (19.9 F) | n/a | n/a |
| Oct | 29.4 C (84.9 F) | -11.1 C (12.0 F) | n/a | n/a |
| Nov | 26.1 C (79.0 F) | -20.6 C (-5.1 F) | n/a | n/a |
| Dec | 20.6 C (69.1 F) | -31.7 C (-25.1 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1948 | 13 |
| 1949 | 34 |
| 1950 | 30 |
| 1951 | 33 |
| 1952 | 11 |
| 1953 | 36 |
| 1954 | 33 |
| 1955 | 25 |
| 1956 | 38 |
| 1957 | 29 |
| 1958 | 15 |
| 1959 | 22 |
| 1960 | 8 |
| 1961 | 27 |
| 1962 | 22 |
| 1963 | 27 |
| 1964 | 32 |
| 1965 | 26 |
| 1966 | 19 |
| 1967 | 26 |
| 1968 | 24 |
| 1969 | 25 |
| 1970 | 9 |
| 1971 | 22 |
| 1972 | 16 |
| 1973 | 11 |
| 1974 | 26 |
| 1975 | 18 |
| 1976 | 32 |
| 1977 | 33 |
| 1978 | 16 |
| 1979 | 38 |
| 1980 | 13 |
| 1981 | 12 |
| 1982 | 27 |
| 1983 | 11 |
| 1984 | 18 |
| 1985 | 13 |
| 1986 | 18 |
| 1987 | 22 |
| 1988 | 23 |
| 1989 | 25 |
| 1990 | 17 |
| 1991 | 12 |
| 1992 | 12 |
| 1993 | 17 |
| 1994 | 11 |
| 1995 | 10 |
| 1996 | 9 |
| 1997 | 5 |
| 1998 | 9 |
| 1999 | 17 |
| 2000 | 14 |
| 2001 | 14 |
| 2002 | 24 |
| 2003 | 16 |
| 2004 | 11 |
| 2005 | 27 |
| 2006 | 21 |
| 2007 | 21 |
| 2008 | 7 |
| 2011 | 16 |
| 2012 | 20 |
| 2013 | 18 |
| 2014 | 14 |
| 2015 | 18 |
| 2016 | 16 |
| 2017 | 34 |
| 2018 | 27 |
| 2019 | 9 |
| 2020 | 21 |
| 2021 | 36 |
| 2022 | 3 |
All-Time Record Progression
7 new records| Date | Kind | Detail |
|---|---|---|
| 1980-12-26 | Record low maximum temperature | Record low maximum temperature -20.6 C (-5.1 F) |
| 1991-08-20 | Record daily precipitation | Record daily precipitation 109.2 mm (4.3 in) |
| 2001-02-06 | Record daily snowfall | Record daily snowfall 61.0 cm (24.0 in) |
| 2001-03-10 | Record snow depth | Record snow depth 101.6 cm (40.0 in) |
| 2004-09-18 | Record daily precipitation | Record daily precipitation 121.9 mm (4.8 in) |
| 2005-10-09 | Record daily precipitation | Record daily precipitation 160.5 mm (6.3 in) |
| 2021-08-12 | Record high minimum temperature | Record high minimum temperature 23.9 C (75.0 F) |
Wettest Day of Each Month
Oct: 160.5 mm (6.3 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 69.3 mm (2.7 in) | 13 January 2018 |
| Feb | 75.9 mm (3.0 in) | 14 February 2008 |
| Mar | 94.0 mm (3.7 in) | 7 March 2011 |
| Apr | 61.7 mm (2.4 in) | 17 April 1996 |
| May | 83.3 mm (3.3 in) | 30 May 1984 |
| Jun | 100.3 mm (3.9 in) | 15 June 1960 |
| Jul | 108.7 mm (4.3 in) | 30 July 2026 |
| Aug | 109.2 mm (4.3 in) | 20 August 1991 |
| Sep | 121.9 mm (4.8 in) | 18 September 2004 |
| Oct | 160.5 mm (6.3 in) | 9 October 2005 |
| Nov | 77.5 mm (3.1 in) | 26 November 1950 |
| Dec | 71.1 mm (2.8 in) | 8 December 2011 |
Period of Record Coverage
1948 to 2022| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1948 | 150 | 41% | No |
| 1949 | 348 | 95% | Yes |
| 1950 | 364 | 100% | Yes |
| 1951 | 365 | 100% | Yes |
| 1952 | 366 | 100% | Yes |
| 1953 | 365 | 100% | Yes |
| 1954 | 365 | 100% | Yes |
| 1955 | 364 | 100% | Yes |
| 1956 | 366 | 100% | Yes |
| 1957 | 365 | 100% | Yes |
| 1958 | 365 | 100% | Yes |
| 1959 | 364 | 100% | Yes |
| 1960 | 366 | 100% | Yes |
| 1961 | 363 | 99% | Yes |
| 1962 | 364 | 100% | Yes |
| 1963 | 365 | 100% | Yes |
| 1964 | 365 | 100% | Yes |
| 1965 | 365 | 100% | Yes |
| 1966 | 365 | 100% | Yes |
| 1967 | 365 | 100% | Yes |
| 1968 | 366 | 100% | Yes |
| 1969 | 364 | 100% | Yes |
| 1970 | 365 | 100% | Yes |
| 1971 | 365 | 100% | Yes |
| 1972 | 366 | 100% | Yes |
| 1973 | 364 | 100% | Yes |
| 1974 | 364 | 100% | Yes |
| 1975 | 365 | 100% | Yes |
| 1976 | 365 | 100% | Yes |
| 1977 | 365 | 100% | Yes |
| 1978 | 359 | 98% | Yes |
| 1979 | 365 | 100% | Yes |
| 1980 | 366 | 100% | Yes |
| 1981 | 365 | 100% | Yes |
| 1982 | 365 | 100% | Yes |
| 1983 | 357 | 98% | Yes |
| 1984 | 364 | 99% | Yes |
| 1985 | 363 | 99% | Yes |
| 1986 | 361 | 99% | Yes |
| 1987 | 362 | 99% | Yes |
| 1988 | 362 | 99% | Yes |
| 1989 | 361 | 99% | Yes |
| 1990 | 338 | 93% | Yes |
| 1991 | 259 | 71% | No |
| 1992 | 266 | 73% | No |
| 1993 | 270 | 74% | No |
| 1994 | 265 | 73% | No |
| 1995 | 199 | 55% | No |
| 1996 | 273 | 75% | No |
| 1997 | 264 | 72% | No |
| 1998 | 271 | 74% | No |
| 1999 | 277 | 76% | No |
| 2000 | 258 | 70% | No |
| 2001 | 318 | 87% | No |
| 2002 | 360 | 99% | Yes |
| 2003 | 274 | 75% | No |
| 2004 | 361 | 99% | Yes |
| 2005 | 360 | 99% | Yes |
| 2006 | 365 | 100% | Yes |
| 2007 | 362 | 99% | Yes |
| 2008 | 213 | 58% | No |
| 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 | 364 | 100% | Yes |
| 2018 | 365 | 100% | Yes |
| 2019 | 364 | 100% | Yes |
| 2020 | 366 | 100% | Yes |
| 2021 | 365 | 100% | Yes |
| 2022 | 120 | 33% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 30 July 2026 | Birch Hill Dam, US | monthly rain | 108.7 mm (4.3 in) | 37.8 mm (1.5 in) | 8 years | 49 of 100 (Notable) |
| 15 May 2026 | Birch Hill Dam, US | daily rain | 35.8 mm (1.4 in) | 15.5 mm (0.6 in) | 53 years | 39 of 100 (Notable) |
| 23 May 2025 | Birch Hill Dam, US | daily rain | 35.6 mm (1.4 in) | 20.9 mm (0.8 in) | 42 years | 41 of 100 (Notable) |
| 5 August 2024 | Birch Hill Dam, US | daily rain | 38.9 mm (1.5 in) | 3.3 mm (0.13 in) | 55 years | 25 of 100 (Routine) |
| 12 April 2024 | Birch Hill Dam, US | daily rain | 23.4 mm (0.9 in) | 8.2 mm (0.32 in) | 59 years | 20 of 100 (Routine) |
| 10 January 2024 | Birch Hill Dam, US | daily rain | 42.2 mm (1.7 in) | 25.7 mm (1.0 in) | 45 years | 46 of 100 (Notable) |
| 18 June 2023 | Birch Hill Dam, US | daily rain | 26.4 mm (1.0 in) | 2.3 mm (0.09 in) | 22 years | 14 of 100 (Routine) |
| 23 January 2023 | Birch Hill Dam, US | daily rain | 24.6 mm (1.0 in) | 3.3 mm (0.13 in) | 36 years | 20 of 100 (Routine) |
| 23 September 2022 | Birch Hill Dam, US | daily rain | 38.4 mm (1.5 in) | 9.7 mm (0.38 in) | 25 years | 20 of 100 (Routine) |
| 6 September 2022 | Birch Hill Dam, US | daily rain | 68.8 mm (2.7 in) | 50.0 mm (2.0 in) | 11 years | 45 of 100 (Notable) |
| 8 April 2022 | Birch Hill Dam, US | daily rain | 19.3 mm (0.8 in) | 4.1 mm (0.16 in) | 65 years | 20 of 100 (Routine) |
| 29 March 2022 | Birch Hill Dam, US | daily low max | -1.7 C (28.9 F) | 1.7 C (3.1 F) | 7 years | 11 of 100 (Routine) |
| 8 March 2022 | Birch Hill Dam, US | daily high min (Tie) | 1.1 C (34.0 F) | tie | 43 years | 4 of 100 (Routine) |
| 7 March 2022 | Birch Hill Dam, US | daily high max (Tie) | 13.9 C (57.0 F) | tie | 48 years | 5 of 100 (Routine) |
| 23 February 2022 | Birch Hill Dam, US | daily rain | 23.1 mm (0.9 in) | 0.2 mm (0.01 in) | 19 years | 12 of 100 (Routine) |
| 18 February 2022 | Birch Hill Dam, US | daily high min | 5.6 C (42.1 F) | 5.0 C (9.0 F) | 71 years | 34 of 100 (Routine) |
| 18 February 2022 | Birch Hill Dam, US | daily high max | 15.0 C (59.0 F) | 1.7 C (3.1 F) | 40 years | 22 of 100 (Routine) |
| 4 February 2022 | Birch Hill Dam, US | daily rain | 59.4 mm (2.3 in) | 36.0 mm (1.4 in) | 40 years | 59 of 100 (Notable) |
| 31 December 2021 | Birch Hill Dam, US | daily high min | 2.2 C (36.0 F) | 0.5 C (0.9 F) | 56 years | 23 of 100 (Routine) |
| 17 December 2021 | Birch Hill Dam, US | daily high min | 7.8 C (46.0 F) | 5.6 C (10.1 F) | 62 years | 33 of 100 (Routine) |
Climate Trend
59 complete years, 1950 to 2021| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1950 | 7.4 C | -0.06 C |
| 1951 | 7.6 C | +0.08 C |
| 1952 | 8.1 C | +0.58 C |
| 1953 | 9.3 C | +1.84 C |
| 1954 | 8.0 C | +0.48 C |
| 1955 | 8.1 C | +0.63 C |
| 1956 | 7.3 C | -0.24 C |
| 1957 | 8.3 C | +0.81 C |
| 1958 | 7.0 C | -0.46 C |
| 1959 | 8.4 C | +0.91 C |
| 1960 | 7.7 C | +0.23 C |
| 1961 | 7.9 C | +0.43 C |
| 1962 | 6.9 C | -0.56 C |
| 1963 | 7.2 C | -0.26 C |
| 1964 | 7.7 C | +0.16 C |
| 1965 | 7.4 C | -0.09 C |
| 1966 | 7.6 C | +0.09 C |
| 1967 | 7.3 C | -0.19 C |
| 1968 | 7.5 C | -0.03 C |
| 1969 | 7.9 C | +0.37 C |
| 1970 | 7.1 C | -0.36 C |
| 1971 | 6.4 C | -1.13 C |
| 1972 | 6.1 C | -1.37 C |
| 1973 | 8.0 C | +0.47 C |
| 1974 | 6.6 C | -0.87 C |
| 1975 | 6.9 C | -0.58 C |
| 1976 | 6.1 C | -1.37 C |
| 1977 | 6.5 C | -1.00 C |
| 1978 | 5.9 C | -1.64 C |
| 1979 | 7.4 C | -0.12 C |
| 1980 | 6.5 C | -0.98 C |
| 1981 | 6.9 C | -0.61 C |
| 1982 | 6.5 C | -1.01 C |
| 1983 | 7.6 C | +0.06 C |
| 1984 | 7.2 C | -0.31 C |
| 1985 | 6.7 C | -0.78 C |
| 1986 | 6.7 C | -0.76 C |
| 1987 | 6.8 C | -0.73 C |
| 1988 | 6.4 C | -1.14 C |
| 1989 | 6.2 C | -1.28 C |
| 1990 | 8.0 C | +0.53 C |
| 1996 | 7.2 C | -0.26 C |
| 1999 | 8.3 C | +0.81 C |
| 2002 | 7.9 C | +0.41 C |
| 2004 | 6.5 C | -1.00 C |
| 2005 | 7.3 C | -0.21 C |
| 2006 | 8.3 C | +0.84 C |
| 2007 | 7.3 C | -0.15 C |
| 2011 | 8.3 C | +0.79 C |
| 2012 | 9.5 C | +1.99 C |
| 2013 | 7.9 C | +0.44 C |
| 2014 | 7.3 C | -0.21 C |
| 2015 | 7.6 C | +0.08 C |
| 2016 | 8.8 C | +1.35 C |
| 2017 | 8.4 C | +0.89 C |
| 2018 | 8.3 C | +0.85 C |
| 2019 | 7.8 C | +0.32 C |
| 2020 | 8.9 C | +1.41 C |
| 2021 | 9.7 C | +2.17 C |
The fitted trend in annual mean temperature here over 1950 to 2021 is 0.10 C (0.00 to 0.20) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.17 F (-0.01 to 0.36) per decade. The slope is a straight line fitted to 59 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.10 C (0.00 to 0.20) per decade | 0.17 F (-0.01 to 0.36) per decade | 1950 to 2021 | 59 | Not clearly different from zero |
| Mean daily maximum | 0.05 C (-0.04 to 0.14) per decade | 0.1 F (-0.1 to 0.2) per decade | 1950 to 2021 | 59 | Not clearly different from zero |
| Mean daily minimum | 0.15 C (0.02 to 0.28) per decade | 0.26 F (0.03 to 0.50) per decade | 1950 to 2021 | 59 | 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
1948 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 37.2 C (99.0 F) | 1948 | 33.9 C (93.0 F) | 73 |
| Coldest night (TNn) | -36.7 C (-34.1 F) | 1957 | -27.8 C (-18.0 F) | 73 |
| Wettest day (Rx1day) | 160.5 mm (6.3 in) | 2005 | 60.2 mm (2.4 in) | 77 |
| Wettest five days (Rx5day) | 191.7 mm (7.5 in) | 2005 | 94.0 mm (3.7 in) | 77 |
| Longest dry spell (CDD) | 38 days | 2001 | 16 days | 77 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1948 | 37.2 C (99.0 F) |
| 1949 | 35.0 C (95.0 F) |
| 1950 | 32.2 C (90.0 F) |
| 1951 | 30.6 C (87.1 F) |
| 1952 | 34.4 C (93.9 F) |
| 1953 | 36.7 C (98.1 F) |
| 1954 | 32.8 C (91.0 F) |
| 1955 | 35.6 C (96.1 F) |
| 1956 | 33.9 C (93.0 F) |
| 1957 | 33.3 C (91.9 F) |
| 1958 | 32.8 C (91.0 F) |
| 1959 | 33.9 C (93.0 F) |
| 1960 | 31.7 C (89.1 F) |
| 1961 | 32.2 C (90.0 F) |
| 1962 | 33.3 C (91.9 F) |
| 1963 | 35.0 C (95.0 F) |
| 1964 | 35.0 C (95.0 F) |
| 1965 | 33.9 C (93.0 F) |
| 1966 | 35.0 C (95.0 F) |
| 1967 | 32.8 C (91.0 F) |
| 1968 | 35.6 C (96.1 F) |
| 1969 | 33.3 C (91.9 F) |
| 1970 | 33.3 C (91.9 F) |
| 1971 | 32.2 C (90.0 F) |
| 1972 | 33.3 C (91.9 F) |
| 1973 | 33.9 C (93.0 F) |
| 1974 | 32.2 C (90.0 F) |
| 1975 | 36.1 C (97.0 F) |
| 1976 | 33.9 C (93.0 F) |
| 1977 | 33.9 C (93.0 F) |
| 1978 | 33.9 C (93.0 F) |
| 1979 | 34.4 C (93.9 F) |
| 1980 | 33.9 C (93.0 F) |
| 1981 | 33.3 C (91.9 F) |
| 1982 | 33.3 C (91.9 F) |
| 1983 | 33.3 C (91.9 F) |
| 1984 | 33.3 C (91.9 F) |
| 1985 | 32.2 C (90.0 F) |
| 1986 | 32.8 C (91.0 F) |
| 1987 | 34.4 C (93.9 F) |
| 1988 | 35.0 C (95.0 F) |
| 1989 | 33.3 C (91.9 F) |
| 1990 | 32.8 C (91.0 F) |
| 1991 | 35.0 C (95.0 F) |
| 1992 | 33.3 C (91.9 F) |
| 1993 | 36.1 C (97.0 F) |
| 1994 | 35.6 C (96.1 F) |
| 1995 | 35.6 C (96.1 F) |
| 1996 | 31.7 C (89.1 F) |
| 1997 | 33.3 C (91.9 F) |
| 1998 | 32.2 C (90.0 F) |
| 1999 | 34.4 C (93.9 F) |
| 2000 | 32.8 C (91.0 F) |
| 2001 | 34.4 C (93.9 F) |
| 2002 | 35.6 C (96.1 F) |
| 2003 | 32.8 C (91.0 F) |
| 2004 | 31.1 C (88.0 F) |
| 2005 | 35.0 C (95.0 F) |
| 2006 | 35.6 C (96.1 F) |
| 2007 | 33.9 C (93.0 F) |
| 2008 | 35.6 C (96.1 F) |
| 2011 | 37.2 C (99.0 F) |
| 2012 | 35.0 C (95.0 F) |
| 2013 | 34.4 C (93.9 F) |
| 2014 | 32.2 C (90.0 F) |
| 2015 | 33.3 C (91.9 F) |
| 2016 | 33.9 C (93.0 F) |
| 2017 | 33.9 C (93.0 F) |
| 2018 | 36.1 C (97.0 F) |
| 2019 | 34.4 C (93.9 F) |
| 2020 | 34.4 C (93.9 F) |
| 2021 | 35.6 C (96.1 F) |
| 2022 | 24.4 C (75.9 F) |
| 2023 | n/a |
| 2024 | n/a |
| 2025 | n/a |
| 2026 | n/a |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1948 | -22.2 C (-8.0 F) |
| 1949 | -27.2 C (-17.0 F) |
| 1950 | -27.8 C (-18.0 F) |
| 1951 | -31.7 C (-25.1 F) |
| 1952 | -22.2 C (-8.0 F) |
| 1953 | -18.9 C (-2.0 F) |
| 1954 | -31.7 C (-25.1 F) |
| 1955 | -25.6 C (-14.1 F) |
| 1956 | -27.2 C (-17.0 F) |
| 1957 | -36.7 C (-34.1 F) |
| 1958 | -30.6 C (-23.1 F) |
| 1959 | -25.0 C (-13.0 F) |
| 1960 | -26.7 C (-16.1 F) |
| 1961 | -34.4 C (-29.9 F) |
| 1962 | -27.8 C (-18.0 F) |
| 1963 | -31.7 C (-25.1 F) |
| 1964 | -30.6 C (-23.1 F) |
| 1965 | -28.3 C (-18.9 F) |
| 1966 | -27.8 C (-18.0 F) |
| 1967 | -31.7 C (-25.1 F) |
| 1968 | -33.3 C (-27.9 F) |
| 1969 | -27.2 C (-17.0 F) |
| 1970 | -30.0 C (-22.0 F) |
| 1971 | -35.0 C (-31.0 F) |
| 1972 | -26.7 C (-16.1 F) |
| 1973 | -25.6 C (-14.1 F) |
| 1974 | -27.2 C (-17.0 F) |
| 1975 | -30.6 C (-23.1 F) |
| 1976 | -33.3 C (-27.9 F) |
| 1977 | -30.6 C (-23.1 F) |
| 1978 | -29.4 C (-20.9 F) |
| 1979 | -27.8 C (-18.0 F) |
| 1980 | -31.1 C (-24.0 F) |
| 1981 | -31.7 C (-25.1 F) |
| 1982 | -32.2 C (-26.0 F) |
| 1983 | -26.1 C (-15.0 F) |
| 1984 | -32.8 C (-27.0 F) |
| 1985 | -27.8 C (-18.0 F) |
| 1986 | -23.3 C (-9.9 F) |
| 1987 | -27.2 C (-17.0 F) |
| 1988 | -31.7 C (-25.1 F) |
| 1989 | -29.4 C (-20.9 F) |
| 1990 | -23.3 C (-9.9 F) |
| 1991 | -25.0 C (-13.0 F) |
| 1992 | -23.3 C (-9.9 F) |
| 1993 | -28.3 C (-18.9 F) |
| 1994 | -33.3 C (-27.9 F) |
| 1995 | -23.3 C (-9.9 F) |
| 1996 | -30.0 C (-22.0 F) |
| 1997 | -23.3 C (-9.9 F) |
| 1998 | -23.3 C (-9.9 F) |
| 1999 | -28.9 C (-20.0 F) |
| 2000 | -25.6 C (-14.1 F) |
| 2001 | -22.8 C (-9.0 F) |
| 2002 | -22.2 C (-8.0 F) |
| 2003 | -27.8 C (-18.0 F) |
| 2004 | -28.9 C (-20.0 F) |
| 2005 | -28.9 C (-20.0 F) |
| 2006 | -22.8 C (-9.0 F) |
| 2007 | -21.1 C (-6.0 F) |
| 2008 | -23.9 C (-11.0 F) |
| 2011 | -27.8 C (-18.0 F) |
| 2012 | -20.6 C (-5.1 F) |
| 2013 | -21.7 C (-7.1 F) |
| 2014 | -25.6 C (-14.1 F) |
| 2015 | -28.9 C (-20.0 F) |
| 2016 | -26.7 C (-16.1 F) |
| 2017 | -25.0 C (-13.0 F) |
| 2018 | -28.3 C (-18.9 F) |
| 2019 | -22.8 C (-9.0 F) |
| 2020 | -20.6 C (-5.1 F) |
| 2021 | -20.6 C (-5.1 F) |
| 2022 | -23.9 C (-11.0 F) |
| 2023 | n/a |
| 2024 | n/a |
| 2025 | n/a |
| 2026 | n/a |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1948 | 51.3 mm (2.0 in) |
| 1949 | 44.5 mm (1.8 in) |
| 1950 | 77.5 mm (3.1 in) |
| 1951 | 66.8 mm (2.6 in) |
| 1952 | 70.9 mm (2.8 in) |
| 1953 | 66.3 mm (2.6 in) |
| 1954 | 69.1 mm (2.7 in) |
| 1955 | 68.6 mm (2.7 in) |
| 1956 | 57.2 mm (2.3 in) |
| 1957 | 41.9 mm (1.6 in) |
| 1958 | 39.4 mm (1.6 in) |
| 1959 | 69.9 mm (2.8 in) |
| 1960 | 100.3 mm (3.9 in) |
| 1961 | 48.3 mm (1.9 in) |
| 1962 | 62.7 mm (2.5 in) |
| 1963 | 43.2 mm (1.7 in) |
| 1964 | 49.0 mm (1.9 in) |
| 1965 | 38.1 mm (1.5 in) |
| 1966 | 39.9 mm (1.6 in) |
| 1967 | 53.8 mm (2.1 in) |
| 1968 | 44.5 mm (1.8 in) |
| 1969 | 50.8 mm (2.0 in) |
| 1970 | 51.6 mm (2.0 in) |
| 1971 | 53.3 mm (2.1 in) |
| 1972 | 67.8 mm (2.7 in) |
| 1973 | 61.7 mm (2.4 in) |
| 1974 | 56.1 mm (2.2 in) |
| 1975 | 55.1 mm (2.2 in) |
| 1976 | 41.9 mm (1.6 in) |
| 1977 | 44.2 mm (1.7 in) |
| 1978 | 51.6 mm (2.0 in) |
| 1979 | 67.6 mm (2.7 in) |
| 1980 | 60.2 mm (2.4 in) |
| 1981 | 43.2 mm (1.7 in) |
| 1982 | 58.4 mm (2.3 in) |
| 1983 | 47.2 mm (1.9 in) |
| 1984 | 83.3 mm (3.3 in) |
| 1985 | 60.2 mm (2.4 in) |
| 1986 | 64.8 mm (2.6 in) |
| 1987 | 49.5 mm (1.9 in) |
| 1988 | 61.0 mm (2.4 in) |
| 1989 | 85.1 mm (3.4 in) |
| 1990 | 57.2 mm (2.3 in) |
| 1991 | 109.2 mm (4.3 in) |
| 1992 | 44.5 mm (1.8 in) |
| 1993 | 44.5 mm (1.8 in) |
| 1994 | 48.3 mm (1.9 in) |
| 1995 | 83.1 mm (3.3 in) |
| 1996 | 63.5 mm (2.5 in) |
| 1997 | 55.9 mm (2.2 in) |
| 1998 | 64.3 mm (2.5 in) |
| 1999 | 97.8 mm (3.9 in) |
| 2000 | 100.3 mm (3.9 in) |
| 2001 | 53.3 mm (2.1 in) |
| 2002 | 57.2 mm (2.3 in) |
| 2003 | 52.1 mm (2.1 in) |
| 2004 | 121.9 mm (4.8 in) |
| 2005 | 160.5 mm (6.3 in) |
| 2006 | 68.6 mm (2.7 in) |
| 2007 | 44.7 mm (1.8 in) |
| 2008 | 75.9 mm (3.0 in) |
| 2011 | 94.0 mm (3.7 in) |
| 2012 | 67.1 mm (2.6 in) |
| 2013 | 61.2 mm (2.4 in) |
| 2014 | 70.9 mm (2.8 in) |
| 2015 | 61.5 mm (2.4 in) |
| 2016 | 50.3 mm (2.0 in) |
| 2017 | 71.1 mm (2.8 in) |
| 2018 | 70.9 mm (2.8 in) |
| 2019 | 65.0 mm (2.6 in) |
| 2020 | 41.4 mm (1.6 in) |
| 2021 | 68.1 mm (2.7 in) |
| 2022 | 68.8 mm (2.7 in) |
| 2023 | 37.1 mm (1.5 in) |
| 2024 | 43.9 mm (1.7 in) |
| 2025 | 41.9 mm (1.6 in) |
| 2026 | 108.7 mm (4.3 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1948 | 66.6 mm (2.6 in) |
| 1949 | 63.5 mm (2.5 in) |
| 1950 | 90.2 mm (3.6 in) |
| 1951 | 75.2 mm (3.0 in) |
| 1952 | 97.6 mm (3.8 in) |
| 1953 | 74.9 mm (2.9 in) |
| 1954 | 78.2 mm (3.1 in) |
| 1955 | 164.1 mm (6.5 in) |
| 1956 | 87.7 mm (3.5 in) |
| 1957 | 60.5 mm (2.4 in) |
| 1958 | 61.0 mm (2.4 in) |
| 1959 | 85.6 mm (3.4 in) |
| 1960 | 130.9 mm (5.2 in) |
| 1961 | 59.2 mm (2.3 in) |
| 1962 | 117.4 mm (4.6 in) |
| 1963 | 60.1 mm (2.4 in) |
| 1964 | 68.6 mm (2.7 in) |
| 1965 | 66.3 mm (2.6 in) |
| 1966 | 58.4 mm (2.3 in) |
| 1967 | 77.4 mm (3.0 in) |
| 1968 | 73.4 mm (2.9 in) |
| 1969 | 97.1 mm (3.8 in) |
| 1970 | 91.0 mm (3.6 in) |
| 1971 | 73.4 mm (2.9 in) |
| 1972 | 81.0 mm (3.2 in) |
| 1973 | 113.6 mm (4.5 in) |
| 1974 | 66.3 mm (2.6 in) |
| 1975 | 151.0 mm (5.9 in) |
| 1976 | 97.5 mm (3.8 in) |
| 1977 | 79.0 mm (3.1 in) |
| 1978 | 59.0 mm (2.3 in) |
| 1979 | 112.1 mm (4.4 in) |
| 1980 | 81.8 mm (3.2 in) |
| 1981 | 89.6 mm (3.5 in) |
| 1982 | 104.3 mm (4.1 in) |
| 1983 | 63.8 mm (2.5 in) |
| 1984 | 184.2 mm (7.3 in) |
| 1985 | 60.2 mm (2.4 in) |
| 1986 | 94.0 mm (3.7 in) |
| 1987 | 96.7 mm (3.8 in) |
| 1988 | 111.1 mm (4.4 in) |
| 1989 | 124.5 mm (4.9 in) |
| 1990 | 112.8 mm (4.4 in) |
| 1991 | 189.9 mm (7.5 in) |
| 1992 | 55.7 mm (2.2 in) |
| 1993 | 89.2 mm (3.5 in) |
| 1994 | 107.2 mm (4.2 in) |
| 1995 | 103.1 mm (4.1 in) |
| 1996 | 113.3 mm (4.5 in) |
| 1997 | 79.6 mm (3.1 in) |
| 1998 | 103.4 mm (4.1 in) |
| 1999 | 108.5 mm (4.3 in) |
| 2000 | 106.6 mm (4.2 in) |
| 2001 | 90.6 mm (3.6 in) |
| 2002 | 74.5 mm (2.9 in) |
| 2003 | 83.5 mm (3.3 in) |
| 2004 | 121.9 mm (4.8 in) |
| 2005 | 191.7 mm (7.5 in) |
| 2006 | 95.9 mm (3.8 in) |
| 2007 | 97.9 mm (3.9 in) |
| 2008 | 116.1 mm (4.6 in) |
| 2011 | 107.9 mm (4.2 in) |
| 2012 | 105.9 mm (4.2 in) |
| 2013 | 102.4 mm (4.0 in) |
| 2014 | 101.1 mm (4.0 in) |
| 2015 | 102.2 mm (4.0 in) |
| 2016 | 83.8 mm (3.3 in) |
| 2017 | 149.6 mm (5.9 in) |
| 2018 | 97.5 mm (3.8 in) |
| 2019 | 75.4 mm (3.0 in) |
| 2020 | 74.6 mm (2.9 in) |
| 2021 | 98.3 mm (3.9 in) |
| 2022 | 95.1 mm (3.7 in) |
| 2023 | 70.1 mm (2.8 in) |
| 2024 | 104.7 mm (4.1 in) |
| 2025 | 57.2 mm (2.3 in) |
| 2026 | 113.1 mm (4.5 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1948 | 17 days |
| 1949 | 25 days |
| 1950 | 16 days |
| 1951 | 14 days |
| 1952 | 25 days |
| 1953 | 15 days |
| 1954 | 14 days |
| 1955 | 25 days |
| 1956 | 15 days |
| 1957 | 19 days |
| 1958 | 21 days |
| 1959 | 14 days |
| 1960 | 12 days |
| 1961 | 17 days |
| 1962 | 12 days |
| 1963 | 27 days |
| 1964 | 19 days |
| 1965 | 20 days |
| 1966 | 29 days |
| 1967 | 11 days |
| 1968 | 18 days |
| 1969 | 13 days |
| 1970 | 16 days |
| 1971 | 13 days |
| 1972 | 13 days |
| 1973 | 15 days |
| 1974 | 15 days |
| 1975 | 25 days |
| 1976 | 20 days |
| 1977 | 14 days |
| 1978 | 17 days |
| 1979 | 18 days |
| 1980 | 23 days |
| 1981 | 14 days |
| 1982 | 17 days |
| 1983 | 17 days |
| 1984 | 19 days |
| 1985 | 14 days |
| 1986 | 12 days |
| 1987 | 19 days |
| 1988 | 15 days |
| 1989 | 12 days |
| 1990 | 14 days |
| 1991 | 16 days |
| 1992 | 12 days |
| 1993 | 13 days |
| 1994 | 14 days |
| 1995 | 29 days |
| 1996 | 31 days |
| 1997 | 18 days |
| 1998 | 19 days |
| 1999 | 19 days |
| 2000 | 11 days |
| 2001 | 38 days |
| 2002 | 12 days |
| 2003 | 9 days |
| 2004 | 17 days |
| 2005 | 13 days |
| 2006 | 17 days |
| 2007 | 25 days |
| 2008 | 14 days |
| 2011 | 11 days |
| 2012 | 19 days |
| 2013 | 13 days |
| 2014 | 18 days |
| 2015 | 19 days |
| 2016 | 17 days |
| 2017 | 9 days |
| 2018 | 14 days |
| 2019 | 9 days |
| 2020 | 19 days |
| 2021 | 16 days |
| 2022 | 20 days |
| 2023 | 25 days |
| 2024 | 11 days |
| 2025 | 15 days |
| 2026 | 10 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
59 years with a frostAcross 59 years with a frost, the median last spring frost at Birch Hill Dam falls on 21 May and the median first autumn frost on 18 September, which leaves a median of 119 days between them.
Fitted over all years, the growing season changes by +6.1 days per decade at this station.
| Measure | Median, all years | Earliest period | Recent period (1979 to 2021) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 21 May | n/a | 14 May | n/a | -2.7 days per decade |
| First autumn frost | 18 September | n/a | 25 September | n/a | +3.4 days per decade |
| Growing days | 119 days | n/a | 136 days | n/a | +6.1 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
64 years, 1949 to 2018A day with at least 57.6 mm (2.3 in) of rain is expected about once in 2 years. A day with at least 146.2 mm (5.8 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 57.6 mm (2.3 in) | |
| 5 years | 74.5 mm (2.9 in) | |
| 10 years | 88.0 mm (3.5 in) | |
| 25 years | 108.3 mm (4.3 in) | |
| 50 years | 126.0 mm (5.0 in) | |
| 100 years | 146.2 mm (5.8 in) | Longer than the 64 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, 64 years of values from 1949 to 2018.
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: 160.5 mm (6.3 in) in 2005; 121.9 mm (4.8 in) in 2004; 109.2 mm (4.3 in) in 1991.
Station Changes
1 suspectedOne change was suspected in the annual mean temperature of Birch Hill Dam, at 2006. Each is measured against neighbouring stations.
- Relative to 5 neighbouring stations, the station's annual mean temperature from 2006 ran 0.4 C (0.6 F) higher than in the years before (likely change).
| Year | Shift (C) | Shift (F) | Strength | Neighbours |
|---|---|---|---|---|
| 2006 | +0.4 | +0.6 | likely | 5 |
Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.
Climate Twins
2004 to 2021 against 1961 to 1990Over 2004 to 2021, Birch Hill Dam had a mean temperature of 8.1 C (46.6 F) and 1,212.2 mm (47.7 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Sanford 2 NNW (United States, 143 km away), Lewiston (United States, 224 km away) and Utica Oneida Co AP (United States, 272 km away).
| Twin station | Country | Distance away | Mean temperature, 1961-1990 | Rain a year, 1961-1990 | Climate difference |
|---|---|---|---|---|---|
| Sanford 2 NNW | United States | 143 km (89 mi) | 8.1 C (46.6 F) | 1,193.1 mm (47.0 in) | 0.64 |
| Lewiston | United States | 224 km (139 mi) | 7.8 C (46.1 F) | 1,149.9 mm (45.3 in) | 0.79 |
| Utica Oneida Co AP | United States | 272 km (169 mi) | 7.8 C (46.0 F) | 1,134.4 mm (44.7 in) | 0.79 |
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 2026-10-17 (17 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-12).