Westby Weather Records (USC00248777)
Record envelope, standing records and threshold days for Westby (USC00248777), Montana, United States, with 90 years of record.
Key Facts for Westby
- Westby (USC00248777) is a weather station in Montana, United States at 48.87 latitude and -104.05 longitude, 641 m (2,103 ft) above sea level.
- The station reports from 1937 to 2026, 90 years of record.
- 1,464 records set at Westby still stand.
- Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
- Westby tied a daily record high minimum temperature of 11.7 C (53.1 F) on 25 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, 48.87 latitude, -104.05 longitude.
- Elevation: 641 m (2,103 ft).
- Period of record: 1937 to 2026, 90 years.
- Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
6 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 13.9 C (57.0 F) | -42.8 C (-45.0 F) | 5.0 C (41.0 F) | -34.4 C (-29.9 F) |
| Feb | 18.9 C (66.0 F) | -41.1 C (-42.0 F) | 8.3 C (46.9 F) | -25.0 C (-13.0 F) |
| Mar | 25.0 C (77.0 F) | -36.1 C (-33.0 F) | 18.9 C (66.0 F) | -20.0 C (-4.0 F) |
| Apr | 32.8 C (91.0 F) | -27.8 C (-18.0 F) | 28.3 C (82.9 F) | -10.0 C (14.0 F) |
| May | 38.9 C (102.0 F) | -12.2 C (10.0 F) | 33.3 C (91.9 F) | -5.6 C (21.9 F) |
| Jun | 39.4 C (102.9 F) | -2.2 C (28.0 F) | 33.9 C (93.0 F) | 3.3 C (37.9 F) |
| Jul | 44.4 C (111.9 F) | 1.7 C (35.1 F) | 36.7 C (98.1 F) | 10.6 C (51.1 F) |
| Aug | 42.2 C (108.0 F) | -1.7 C (28.9 F) | 35.0 C (95.0 F) | 6.1 C (43.0 F) |
| Sep | 39.4 C (102.9 F) | -9.4 C (15.1 F) | 30.6 C (87.1 F) | 5.0 C (41.0 F) |
| Oct | 33.3 C (91.9 F) | -21.1 C (-6.0 F) | n/a | n/a |
| Nov | 22.8 C (73.0 F) | -32.2 C (-26.0 F) | n/a | n/a |
| Dec | 16.1 C (61.0 F) | -41.1 C (-42.0 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1937 | 32 |
| 1938 | 14 |
| 1939 | 35 |
| 1940 | 21 |
| 1941 | 10 |
| 1942 | 22 |
| 1943 | 30 |
| 1944 | 19 |
| 1945 | 20 |
| 1946 | 10 |
| 1947 | 17 |
| 1948 | 15 |
| 1949 | 23 |
| 1950 | 16 |
| 1951 | 24 |
| 1952 | 14 |
| 1953 | 14 |
| 1954 | 22 |
| 1955 | 9 |
| 1956 | 12 |
| 1957 | 11 |
| 1958 | 20 |
| 1959 | 21 |
| 1960 | 9 |
| 1961 | 19 |
| 1962 | 18 |
| 1963 | 22 |
| 1964 | 21 |
| 1965 | 16 |
| 1966 | 16 |
| 1967 | 12 |
| 1968 | 17 |
| 1969 | 22 |
| 1970 | 8 |
| 1971 | 8 |
| 1972 | 22 |
| 1973 | 11 |
| 1974 | 11 |
| 1975 | 9 |
| 1976 | 10 |
| 1977 | 23 |
| 1978 | 13 |
| 1979 | 8 |
| 1980 | 20 |
| 1981 | 17 |
| 1982 | 15 |
| 1983 | 29 |
| 1984 | 18 |
| 1985 | 4 |
| 1987 | 13 |
| 1988 | 20 |
| 1989 | 21 |
| 1990 | 12 |
| 1991 | 24 |
| 1992 | 33 |
| 1993 | 16 |
| 1994 | 9 |
| 1995 | 16 |
| 1996 | 25 |
| 1997 | 16 |
| 1998 | 9 |
| 1999 | 14 |
| 2000 | 21 |
| 2001 | 12 |
| 2002 | 27 |
| 2003 | 24 |
| 2004 | 14 |
| 2005 | 22 |
| 2006 | 6 |
| 2007 | 16 |
| 2008 | 13 |
| 2009 | 25 |
| 2010 | 3 |
| 2011 | 6 |
| 2012 | 12 |
| 2013 | 11 |
| 2014 | 15 |
| 2015 | 16 |
| 2016 | 6 |
| 2017 | 15 |
| 2018 | 23 |
| 2019 | 5 |
| 2020 | 19 |
| 2021 | 21 |
| 2022 | 7 |
| 2023 | 16 |
| 2024 | 20 |
| 2025 | 19 |
| 2026 | 13 |
All-Time Record Progression
4 new records| Date | Kind | Detail |
|---|---|---|
| 1975-07-29 | Record high minimum temperature | Record high minimum temperature 22.8 C (73.0 F) |
| 1983-12-23 | Record low maximum temperature | Record low maximum temperature -34.4 C (-29.9 F) |
| 1984-07-29 | Record high minimum temperature | Record high minimum temperature 24.4 C (75.9 F) |
| 1990-07-02 | Record daily precipitation | Record daily precipitation 114.3 mm (4.5 in) |
Wettest Day of Each Month
Jul: 114.3 mm (4.5 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 50.8 mm (2.0 in) | 13 January 2011 |
| Feb | 22.9 mm (0.9 in) | 11 February 2016 |
| Mar | 24.9 mm (1.0 in) | 17 March 1943 |
| Apr | 37.1 mm (1.5 in) | 19 April 1955 |
| May | 76.7 mm (3.0 in) | 25 May 1942 |
| Jun | 73.7 mm (2.9 in) | 3 June 1953 |
| Jul | 114.3 mm (4.5 in) | 2 July 1990 |
| Aug | 66.0 mm (2.6 in) | 14 August 2026 |
| Sep | 55.1 mm (2.2 in) | 16 September 1963 |
| Oct | 35.8 mm (1.4 in) | 5 October 1937 |
| Nov | 45.5 mm (1.8 in) | 2 November 2000 |
| Dec | 24.1 mm (0.9 in) | 30 December 1965 |
Period of Record Coverage
1937 to 2026| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1937 | 365 | 100% | Yes |
| 1938 | 364 | 100% | Yes |
| 1939 | 365 | 100% | Yes |
| 1940 | 366 | 100% | Yes |
| 1941 | 365 | 100% | Yes |
| 1942 | 365 | 100% | Yes |
| 1943 | 364 | 100% | Yes |
| 1944 | 366 | 100% | Yes |
| 1945 | 365 | 100% | Yes |
| 1946 | 302 | 83% | No |
| 1947 | 364 | 100% | Yes |
| 1948 | 364 | 99% | Yes |
| 1949 | 365 | 100% | Yes |
| 1950 | 365 | 100% | Yes |
| 1951 | 365 | 100% | Yes |
| 1952 | 366 | 100% | Yes |
| 1953 | 364 | 100% | Yes |
| 1954 | 364 | 100% | Yes |
| 1955 | 324 | 89% | No |
| 1956 | 319 | 87% | No |
| 1957 | 250 | 68% | No |
| 1958 | 229 | 63% | No |
| 1959 | 278 | 76% | No |
| 1960 | 364 | 99% | Yes |
| 1961 | 357 | 98% | Yes |
| 1962 | 361 | 99% | Yes |
| 1963 | 363 | 99% | Yes |
| 1964 | 361 | 99% | Yes |
| 1965 | 363 | 99% | Yes |
| 1966 | 356 | 98% | Yes |
| 1967 | 363 | 99% | Yes |
| 1968 | 356 | 97% | Yes |
| 1969 | 355 | 97% | Yes |
| 1970 | 360 | 99% | Yes |
| 1971 | 352 | 96% | Yes |
| 1972 | 347 | 95% | Yes |
| 1973 | 348 | 95% | Yes |
| 1974 | 353 | 97% | Yes |
| 1975 | 348 | 95% | Yes |
| 1976 | 338 | 92% | Yes |
| 1977 | 345 | 95% | Yes |
| 1978 | 345 | 95% | Yes |
| 1979 | 349 | 96% | Yes |
| 1980 | 332 | 91% | Yes |
| 1981 | 331 | 91% | Yes |
| 1982 | 341 | 93% | Yes |
| 1983 | 332 | 91% | Yes |
| 1984 | 319 | 87% | No |
| 1985 | 141 | 39% | No |
| 1987 | 171 | 47% | No |
| 1988 | 345 | 94% | Yes |
| 1989 | 342 | 94% | Yes |
| 1990 | 355 | 97% | Yes |
| 1991 | 365 | 100% | Yes |
| 1992 | 357 | 98% | Yes |
| 1993 | 336 | 92% | Yes |
| 1994 | 337 | 92% | Yes |
| 1995 | 345 | 95% | Yes |
| 1996 | 352 | 96% | Yes |
| 1997 | 365 | 100% | Yes |
| 1998 | 364 | 100% | Yes |
| 1999 | 364 | 100% | Yes |
| 2000 | 361 | 99% | Yes |
| 2001 | 354 | 97% | Yes |
| 2002 | 364 | 100% | Yes |
| 2003 | 364 | 100% | Yes |
| 2004 | 321 | 88% | No |
| 2005 | 365 | 100% | Yes |
| 2006 | 320 | 88% | No |
| 2007 | 359 | 98% | Yes |
| 2008 | 363 | 99% | Yes |
| 2009 | 358 | 98% | Yes |
| 2010 | 356 | 98% | Yes |
| 2011 | 350 | 96% | Yes |
| 2012 | 217 | 59% | No |
| 2013 | 278 | 76% | No |
| 2014 | 300 | 82% | No |
| 2015 | 313 | 86% | No |
| 2016 | 364 | 99% | Yes |
| 2017 | 281 | 77% | No |
| 2018 | 267 | 73% | No |
| 2019 | 277 | 76% | No |
| 2020 | 343 | 94% | Yes |
| 2021 | 364 | 100% | Yes |
| 2022 | 309 | 85% | No |
| 2023 | 357 | 98% | Yes |
| 2024 | 365 | 100% | Yes |
| 2025 | 365 | 100% | Yes |
| 2026 | 258 | 71% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 25 September 2026 | Westby, US | daily high min (Tie, Provisional) | 11.7 C (53.1 F) | tie | 12 years | 3 of 100 (Routine) |
| 6 September 2026 | Westby, US | daily high min (Provisional) | 18.3 C (64.9 F) | 2.2 C (4.0 F) | 88 years | 39 of 100 (Notable) |
| 14 August 2026 | Westby, US | monthly rain | 66.0 mm (2.6 in) | 1.7 mm (0.07 in) | 61 years | 39 of 100 (Notable) |
| 7 August 2026 | Westby, US | daily low min (Tie) | 6.7 C (44.1 F) | tie | 61 years | 6 of 100 (Routine) |
| 4 August 2026 | Westby, US | daily low min (Tie) | 6.1 C (43.0 F) | tie | 48 years | 5 of 100 (Routine) |
| 13 July 2026 | Westby, US | daily high min | 21.7 C (71.1 F) | 2.8 C (5.0 F) | 72 years | 38 of 100 (Notable) |
| 22 June 2026 | Westby, US | daily rain | 28.2 mm (1.1 in) | 0.3 mm (0.01 in) | 41 years | 21 of 100 (Routine) |
| 14 June 2026 | Westby, US | daily low min | 3.3 C (37.9 F) | 0.6 C (1.1 F) | 36 years | 21 of 100 (Routine) |
| 31 May 2026 | Westby, US | daily high min | 16.7 C (62.1 F) | 2.8 C (5.0 F) | 81 years | 39 of 100 (Notable) |
| 29 May 2026 | Westby, US | monthly high min | 18.3 C (64.9 F) | 0.5 C (0.9 F) | 78 years | 43 of 100 (Notable) |
| 28 May 2026 | Westby, US | daily high min | 16.1 C (61.0 F) | 1.7 C (3.1 F) | 80 years | 36 of 100 (Notable) |
| 6 May 2026 | Westby, US | daily low min (Tie) | -5.6 C (21.9 F) | tie | 53 years | 6 of 100 (Routine) |
| 26 April 2026 | Westby, US | daily low max | -0.6 C (30.9 F) | 1.2 C (2.2 F) | 60 years | 28 of 100 (Routine) |
| 23 April 2026 | Westby, US | daily high max | 28.3 C (82.9 F) | 2.2 C (4.0 F) | 28 years | 19 of 100 (Routine) |
| 18 April 2026 | Westby, US | daily low max | -3.3 C (26.1 F) | 2.2 C (4.0 F) | 15 years | 15 of 100 (Routine) |
| 30 March 2026 | Westby, US | daily rain | 11.7 mm (0.5 in) | 4.8 mm (0.19 in) | 88 years | 20 of 100 (Routine) |
| 21 March 2026 | Westby, US | daily high min | 2.8 C (37.0 F) | 2.2 C (4.0 F) | 80 years | 35 of 100 (Notable) |
| 19 March 2026 | Westby, US | daily high min | 2.8 C (37.0 F) | 1.7 C (3.1 F) | 88 years | 37 of 100 (Notable) |
| 9 March 2026 | Westby, US | daily high max (Tie) | 15.0 C (59.0 F) | tie | 11 years | 3 of 100 (Routine) |
| 8 March 2026 | Westby, US | daily high min (Tie) | -1.7 C (28.9 F) | tie | 57 years | 6 of 100 (Routine) |
Climate Trend
63 complete years, 1937 to 2025| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1937 | 4.0 C | -0.31 C |
| 1938 | 5.4 C | +1.07 C |
| 1939 | 5.0 C | +0.73 C |
| 1940 | 4.1 C | -0.18 C |
| 1941 | 4.9 C | +0.63 C |
| 1942 | 4.3 C | +0.01 C |
| 1943 | 3.8 C | -0.50 C |
| 1944 | 5.4 C | +1.09 C |
| 1945 | 3.7 C | -0.58 C |
| 1947 | 4.3 C | +0.04 C |
| 1948 | 4.2 C | -0.08 C |
| 1949 | 4.2 C | -0.08 C |
| 1950 | 1.8 C | -2.45 C |
| 1951 | 1.8 C | -2.52 C |
| 1952 | 4.7 C | +0.41 C |
| 1953 | 5.7 C | +1.44 C |
| 1954 | 4.7 C | +0.45 C |
| 1960 | 4.3 C | +0.01 C |
| 1961 | 5.4 C | +1.11 C |
| 1962 | 4.7 C | +0.43 C |
| 1963 | 5.7 C | +1.41 C |
| 1964 | 4.4 C | +0.15 C |
| 1965 | 3.1 C | -1.17 C |
| 1966 | 3.6 C | -0.74 C |
| 1967 | 4.4 C | +0.11 C |
| 1968 | 4.7 C | +0.44 C |
| 1969 | 4.1 C | -0.19 C |
| 1970 | 4.0 C | -0.31 C |
| 1971 | 4.6 C | +0.32 C |
| 1972 | 3.6 C | -0.69 C |
| 1973 | 5.9 C | +1.63 C |
| 1974 | 4.8 C | +0.55 C |
| 1975 | 3.9 C | -0.39 C |
| 1976 | 5.3 C | +1.01 C |
| 1977 | 5.2 C | +0.92 C |
| 1978 | 3.7 C | -0.58 C |
| 1979 | 3.5 C | -0.78 C |
| 1980 | 5.6 C | +1.28 C |
| 1982 | 2.9 C | -1.35 C |
| 1983 | 5.2 C | +0.94 C |
| 1991 | 4.9 C | +0.63 C |
| 1992 | 4.6 C | +0.27 C |
| 1994 | 3.4 C | -0.91 C |
| 1996 | 1.6 C | -2.68 C |
| 1997 | 4.0 C | -0.26 C |
| 1998 | 5.1 C | +0.85 C |
| 1999 | 5.0 C | +0.67 C |
| 2000 | 3.6 C | -0.72 C |
| 2001 | 4.6 C | +0.34 C |
| 2002 | 3.4 C | -0.85 C |
| 2003 | 3.5 C | -0.78 C |
| 2005 | 4.5 C | +0.25 C |
| 2007 | 4.4 C | +0.10 C |
| 2008 | 3.3 C | -0.99 C |
| 2009 | 2.5 C | -1.83 C |
| 2010 | 3.3 C | -0.99 C |
| 2011 | 3.8 C | -0.47 C |
| 2016 | 6.1 C | +1.79 C |
| 2021 | 5.2 C | +0.86 C |
| 2022 | 3.3 C | -0.98 C |
| 2023 | 5.2 C | +0.94 C |
| 2024 | 5.5 C | +1.17 C |
| 2025 | 4.4 C | +0.14 C |
The fitted trend in annual mean temperature here over 1937 to 2025 is -0.01 C (-0.11 to 0.08) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.03 F (-0.20 to 0.15) per decade. The slope is a straight line fitted to 63 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | -0.01 C (-0.11 to 0.08) per decade | -0.03 F (-0.20 to 0.15) per decade | 1937 to 2025 | 63 | Not clearly different from zero |
| Mean daily maximum | -0.07 C (-0.18 to 0.03) per decade | -0.1 F (-0.3 to 0.1) per decade | 1937 to 2025 | 63 | Not clearly different from zero |
| Mean daily minimum | 0.05 C (-0.05 to 0.14) per decade | 0.1 F (-0.1 to 0.3) per decade | 1937 to 2025 | 63 | Not clearly different from zero |
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
1937 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 44.4 C (111.9 F) | 1937 | 37.8 C (100.0 F) | 89 |
| Coldest night (TNn) | -42.8 C (-45.0 F) | 1943 | -35.6 C (-32.1 F) | 89 |
| Wettest day (Rx1day) | 114.3 mm (4.5 in) | 1990 | 34.0 mm (1.3 in) | 89 |
| Wettest five days (Rx5day) | 131.5 mm (5.2 in) | 1965 | 50.6 mm (2.0 in) | 89 |
| Longest dry spell (CDD) | 77 days | 1960 | 37 days | 89 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1937 | 44.4 C (111.9 F) |
| 1938 | 35.6 C (96.1 F) |
| 1939 | 38.3 C (100.9 F) |
| 1940 | 39.4 C (102.9 F) |
| 1941 | 38.9 C (102.0 F) |
| 1942 | 37.8 C (100.0 F) |
| 1943 | 35.0 C (95.0 F) |
| 1944 | 36.7 C (98.1 F) |
| 1945 | 37.8 C (100.0 F) |
| 1946 | 36.1 C (97.0 F) |
| 1947 | 40.6 C (105.1 F) |
| 1948 | 39.4 C (102.9 F) |
| 1949 | 40.0 C (104.0 F) |
| 1950 | 37.8 C (100.0 F) |
| 1951 | 40.6 C (105.1 F) |
| 1952 | 39.4 C (102.9 F) |
| 1953 | 33.3 C (91.9 F) |
| 1954 | 34.4 C (93.9 F) |
| 1955 | 38.3 C (100.9 F) |
| 1956 | 38.3 C (100.9 F) |
| 1957 | 37.8 C (100.0 F) |
| 1958 | 41.7 C (107.1 F) |
| 1959 | 36.7 C (98.1 F) |
| 1960 | 40.0 C (104.0 F) |
| 1961 | 39.4 C (102.9 F) |
| 1962 | 35.0 C (95.0 F) |
| 1963 | 40.0 C (104.0 F) |
| 1964 | 38.9 C (102.0 F) |
| 1965 | 37.2 C (99.0 F) |
| 1966 | 38.3 C (100.9 F) |
| 1967 | 37.2 C (99.0 F) |
| 1968 | 37.8 C (100.0 F) |
| 1969 | 37.8 C (100.0 F) |
| 1970 | 37.8 C (100.0 F) |
| 1971 | 39.4 C (102.9 F) |
| 1972 | 36.1 C (97.0 F) |
| 1973 | 37.2 C (99.0 F) |
| 1974 | 39.4 C (102.9 F) |
| 1975 | 41.7 C (107.1 F) |
| 1976 | 40.0 C (104.0 F) |
| 1977 | 36.7 C (98.1 F) |
| 1978 | 38.9 C (102.0 F) |
| 1979 | 38.3 C (100.9 F) |
| 1980 | 39.4 C (102.9 F) |
| 1981 | 37.8 C (100.0 F) |
| 1982 | 36.7 C (98.1 F) |
| 1983 | 42.2 C (108.0 F) |
| 1984 | 40.6 C (105.1 F) |
| 1985 | 33.3 C (91.9 F) |
| 1987 | 35.0 C (95.0 F) |
| 1988 | 39.4 C (102.9 F) |
| 1989 | 39.4 C (102.9 F) |
| 1990 | 37.8 C (100.0 F) |
| 1991 | 35.6 C (96.1 F) |
| 1992 | 34.4 C (93.9 F) |
| 1993 | 32.8 C (91.0 F) |
| 1994 | 35.6 C (96.1 F) |
| 1995 | 37.8 C (100.0 F) |
| 1996 | 35.0 C (95.0 F) |
| 1997 | 33.3 C (91.9 F) |
| 1998 | 37.2 C (99.0 F) |
| 1999 | 36.7 C (98.1 F) |
| 2000 | 35.0 C (95.0 F) |
| 2001 | 36.7 C (98.1 F) |
| 2002 | 36.1 C (97.0 F) |
| 2003 | 37.2 C (99.0 F) |
| 2004 | 33.3 C (91.9 F) |
| 2005 | 36.1 C (97.0 F) |
| 2006 | 36.1 C (97.0 F) |
| 2007 | 41.1 C (106.0 F) |
| 2008 | 35.6 C (96.1 F) |
| 2009 | 36.1 C (97.0 F) |
| 2010 | 33.9 C (93.0 F) |
| 2011 | 35.0 C (95.0 F) |
| 2012 | 32.2 C (90.0 F) |
| 2013 | 33.9 C (93.0 F) |
| 2014 | 35.0 C (95.0 F) |
| 2015 | 38.9 C (102.0 F) |
| 2016 | 36.1 C (97.0 F) |
| 2017 | 32.8 C (91.0 F) |
| 2018 | 40.0 C (104.0 F) |
| 2019 | 34.4 C (93.9 F) |
| 2020 | 36.7 C (98.1 F) |
| 2021 | 37.8 C (100.0 F) |
| 2022 | 37.8 C (100.0 F) |
| 2023 | 37.8 C (100.0 F) |
| 2024 | 40.6 C (105.1 F) |
| 2025 | 36.1 C (97.0 F) |
| 2026 | 36.7 C (98.1 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1937 | -40.6 C (-41.1 F) |
| 1938 | -36.7 C (-34.1 F) |
| 1939 | -40.0 C (-40.0 F) |
| 1940 | -37.8 C (-36.0 F) |
| 1941 | -32.2 C (-26.0 F) |
| 1942 | -35.0 C (-31.0 F) |
| 1943 | -42.8 C (-45.0 F) |
| 1944 | -35.0 C (-31.0 F) |
| 1945 | -35.0 C (-31.0 F) |
| 1946 | -31.7 C (-25.1 F) |
| 1947 | -35.6 C (-32.1 F) |
| 1948 | -36.1 C (-33.0 F) |
| 1949 | -36.7 C (-34.1 F) |
| 1950 | -41.1 C (-42.0 F) |
| 1951 | -39.4 C (-38.9 F) |
| 1952 | -34.4 C (-29.9 F) |
| 1953 | -36.1 C (-33.0 F) |
| 1954 | -42.8 C (-45.0 F) |
| 1955 | -32.8 C (-27.0 F) |
| 1956 | -34.4 C (-29.9 F) |
| 1957 | -36.7 C (-34.1 F) |
| 1958 | -30.6 C (-23.1 F) |
| 1959 | -35.6 C (-32.1 F) |
| 1960 | -32.8 C (-27.0 F) |
| 1961 | -34.4 C (-29.9 F) |
| 1962 | -41.1 C (-42.0 F) |
| 1963 | -34.4 C (-29.9 F) |
| 1964 | -33.9 C (-29.0 F) |
| 1965 | -39.4 C (-38.9 F) |
| 1966 | -38.3 C (-36.9 F) |
| 1967 | -35.6 C (-32.1 F) |
| 1968 | -37.2 C (-35.0 F) |
| 1969 | -42.8 C (-45.0 F) |
| 1970 | -38.3 C (-36.9 F) |
| 1971 | -35.0 C (-31.0 F) |
| 1972 | -36.1 C (-33.0 F) |
| 1973 | -33.3 C (-27.9 F) |
| 1974 | -37.2 C (-35.0 F) |
| 1975 | -33.3 C (-27.9 F) |
| 1976 | -36.7 C (-34.1 F) |
| 1977 | -37.2 C (-35.0 F) |
| 1978 | -37.2 C (-35.0 F) |
| 1979 | -35.0 C (-31.0 F) |
| 1980 | -34.4 C (-29.9 F) |
| 1981 | -31.7 C (-25.1 F) |
| 1982 | -38.3 C (-36.9 F) |
| 1983 | -41.1 C (-42.0 F) |
| 1984 | -35.6 C (-32.1 F) |
| 1985 | -34.4 C (-29.9 F) |
| 1987 | -25.6 C (-14.1 F) |
| 1988 | -33.3 C (-27.9 F) |
| 1989 | -37.8 C (-36.0 F) |
| 1990 | -37.2 C (-35.0 F) |
| 1991 | -36.1 C (-33.0 F) |
| 1992 | -32.8 C (-27.0 F) |
| 1993 | -37.2 C (-35.0 F) |
| 1994 | -38.9 C (-38.0 F) |
| 1995 | -30.0 C (-22.0 F) |
| 1996 | -38.9 C (-38.0 F) |
| 1997 | -36.1 C (-33.0 F) |
| 1998 | -33.9 C (-29.0 F) |
| 1999 | -33.9 C (-29.0 F) |
| 2000 | -31.7 C (-25.1 F) |
| 2001 | -30.6 C (-23.1 F) |
| 2002 | -33.9 C (-29.0 F) |
| 2003 | -35.0 C (-31.0 F) |
| 2004 | -36.1 C (-33.0 F) |
| 2005 | -40.0 C (-40.0 F) |
| 2006 | -33.3 C (-27.9 F) |
| 2007 | -32.8 C (-27.0 F) |
| 2008 | -35.0 C (-31.0 F) |
| 2009 | -41.1 C (-42.0 F) |
| 2010 | -35.6 C (-32.1 F) |
| 2011 | -35.6 C (-32.1 F) |
| 2012 | -32.8 C (-27.0 F) |
| 2013 | -35.6 C (-32.1 F) |
| 2014 | -34.4 C (-29.9 F) |
| 2015 | -32.2 C (-26.0 F) |
| 2016 | -33.9 C (-29.0 F) |
| 2017 | -35.0 C (-31.0 F) |
| 2018 | -36.1 C (-33.0 F) |
| 2019 | -27.8 C (-18.0 F) |
| 2020 | -32.8 C (-27.0 F) |
| 2021 | -38.3 C (-36.9 F) |
| 2022 | -35.6 C (-32.1 F) |
| 2023 | -32.8 C (-27.0 F) |
| 2024 | -36.1 C (-33.0 F) |
| 2025 | -36.1 C (-33.0 F) |
| 2026 | -34.4 C (-29.9 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1937 | 52.6 mm (2.1 in) |
| 1938 | 36.3 mm (1.4 in) |
| 1939 | 34.0 mm (1.3 in) |
| 1940 | 28.4 mm (1.1 in) |
| 1941 | 49.5 mm (1.9 in) |
| 1942 | 76.7 mm (3.0 in) |
| 1943 | 47.0 mm (1.9 in) |
| 1944 | 38.1 mm (1.5 in) |
| 1945 | 29.2 mm (1.1 in) |
| 1946 | 26.2 mm (1.0 in) |
| 1947 | 39.9 mm (1.6 in) |
| 1948 | 36.8 mm (1.4 in) |
| 1949 | 33.0 mm (1.3 in) |
| 1950 | 58.4 mm (2.3 in) |
| 1951 | 33.5 mm (1.3 in) |
| 1952 | 54.6 mm (2.1 in) |
| 1953 | 73.7 mm (2.9 in) |
| 1954 | 42.2 mm (1.7 in) |
| 1955 | 37.1 mm (1.5 in) |
| 1956 | 20.3 mm (0.8 in) |
| 1957 | 18.3 mm (0.7 in) |
| 1958 | 16.5 mm (0.6 in) |
| 1959 | 30.5 mm (1.2 in) |
| 1960 | 50.5 mm (2.0 in) |
| 1961 | 17.3 mm (0.7 in) |
| 1962 | 35.6 mm (1.4 in) |
| 1963 | 55.1 mm (2.2 in) |
| 1964 | 21.6 mm (0.9 in) |
| 1965 | 64.3 mm (2.5 in) |
| 1966 | 34.5 mm (1.4 in) |
| 1967 | 27.9 mm (1.1 in) |
| 1968 | 42.2 mm (1.7 in) |
| 1969 | 27.2 mm (1.1 in) |
| 1970 | 26.7 mm (1.1 in) |
| 1971 | 34.8 mm (1.4 in) |
| 1972 | 42.4 mm (1.7 in) |
| 1973 | 34.5 mm (1.4 in) |
| 1974 | 21.3 mm (0.8 in) |
| 1975 | 28.7 mm (1.1 in) |
| 1976 | 33.3 mm (1.3 in) |
| 1977 | 31.2 mm (1.2 in) |
| 1978 | 41.4 mm (1.6 in) |
| 1979 | 27.2 mm (1.1 in) |
| 1980 | 26.4 mm (1.0 in) |
| 1981 | 25.4 mm (1.0 in) |
| 1982 | 37.3 mm (1.5 in) |
| 1983 | 20.6 mm (0.8 in) |
| 1984 | 27.9 mm (1.1 in) |
| 1985 | 21.3 mm (0.8 in) |
| 1987 | 53.3 mm (2.1 in) |
| 1988 | 31.2 mm (1.2 in) |
| 1989 | 35.1 mm (1.4 in) |
| 1990 | 114.3 mm (4.5 in) |
| 1991 | 30.5 mm (1.2 in) |
| 1992 | 27.9 mm (1.1 in) |
| 1993 | 55.4 mm (2.2 in) |
| 1994 | 41.1 mm (1.6 in) |
| 1995 | 21.1 mm (0.8 in) |
| 1996 | 44.5 mm (1.8 in) |
| 1997 | 57.7 mm (2.3 in) |
| 1998 | 38.6 mm (1.5 in) |
| 1999 | 28.4 mm (1.1 in) |
| 2000 | 45.5 mm (1.8 in) |
| 2001 | 25.7 mm (1.0 in) |
| 2002 | 26.4 mm (1.0 in) |
| 2003 | 38.1 mm (1.5 in) |
| 2004 | 34.8 mm (1.4 in) |
| 2005 | 42.4 mm (1.7 in) |
| 2006 | 40.6 mm (1.6 in) |
| 2007 | 47.0 mm (1.9 in) |
| 2008 | 29.0 mm (1.1 in) |
| 2009 | 20.8 mm (0.8 in) |
| 2010 | 32.8 mm (1.3 in) |
| 2011 | 50.8 mm (2.0 in) |
| 2012 | 18.8 mm (0.7 in) |
| 2013 | 26.4 mm (1.0 in) |
| 2014 | 29.5 mm (1.2 in) |
| 2015 | 29.2 mm (1.1 in) |
| 2016 | 34.3 mm (1.4 in) |
| 2017 | 20.8 mm (0.8 in) |
| 2018 | 21.3 mm (0.8 in) |
| 2019 | 47.8 mm (1.9 in) |
| 2020 | 20.3 mm (0.8 in) |
| 2021 | 24.9 mm (1.0 in) |
| 2022 | 31.8 mm (1.3 in) |
| 2023 | 21.6 mm (0.9 in) |
| 2024 | 45.7 mm (1.8 in) |
| 2025 | 48.8 mm (1.9 in) |
| 2026 | 66.0 mm (2.6 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1937 | 93.9 mm (3.7 in) |
| 1938 | 55.4 mm (2.2 in) |
| 1939 | 53.4 mm (2.1 in) |
| 1940 | 52.2 mm (2.1 in) |
| 1941 | 69.6 mm (2.7 in) |
| 1942 | 97.3 mm (3.8 in) |
| 1943 | 62.5 mm (2.5 in) |
| 1944 | 63.5 mm (2.5 in) |
| 1945 | 42.1 mm (1.7 in) |
| 1946 | 42.5 mm (1.7 in) |
| 1947 | 59.5 mm (2.3 in) |
| 1948 | 43.9 mm (1.7 in) |
| 1949 | 41.2 mm (1.6 in) |
| 1950 | 72.4 mm (2.9 in) |
| 1951 | 50.6 mm (2.0 in) |
| 1952 | 92.2 mm (3.6 in) |
| 1953 | 82.2 mm (3.2 in) |
| 1954 | 61.2 mm (2.4 in) |
| 1955 | 55.6 mm (2.2 in) |
| 1956 | 37.3 mm (1.5 in) |
| 1957 | 33.4 mm (1.3 in) |
| 1958 | 16.5 mm (0.6 in) |
| 1959 | 75.2 mm (3.0 in) |
| 1960 | 64.0 mm (2.5 in) |
| 1961 | 22.2 mm (0.9 in) |
| 1962 | 44.2 mm (1.7 in) |
| 1963 | 72.4 mm (2.9 in) |
| 1964 | 53.8 mm (2.1 in) |
| 1965 | 131.5 mm (5.2 in) |
| 1966 | 54.3 mm (2.1 in) |
| 1967 | 38.5 mm (1.5 in) |
| 1968 | 89.9 mm (3.5 in) |
| 1969 | 71.5 mm (2.8 in) |
| 1970 | 38.9 mm (1.5 in) |
| 1971 | 44.0 mm (1.7 in) |
| 1972 | 70.6 mm (2.8 in) |
| 1973 | 88.7 mm (3.5 in) |
| 1974 | 38.1 mm (1.5 in) |
| 1975 | 46.2 mm (1.8 in) |
| 1976 | 54.1 mm (2.1 in) |
| 1977 | 51.2 mm (2.0 in) |
| 1978 | 76.8 mm (3.0 in) |
| 1979 | 33.5 mm (1.3 in) |
| 1980 | 40.9 mm (1.6 in) |
| 1981 | 36.8 mm (1.4 in) |
| 1982 | 49.0 mm (1.9 in) |
| 1983 | 28.7 mm (1.1 in) |
| 1984 | 28.7 mm (1.1 in) |
| 1985 | 28.2 mm (1.1 in) |
| 1987 | 79.2 mm (3.1 in) |
| 1988 | 31.2 mm (1.2 in) |
| 1989 | 36.4 mm (1.4 in) |
| 1990 | 127.2 mm (5.0 in) |
| 1991 | 41.1 mm (1.6 in) |
| 1992 | 45.2 mm (1.8 in) |
| 1993 | 121.2 mm (4.8 in) |
| 1994 | 50.6 mm (2.0 in) |
| 1995 | 33.0 mm (1.3 in) |
| 1996 | 47.3 mm (1.9 in) |
| 1997 | 74.3 mm (2.9 in) |
| 1998 | 65.5 mm (2.6 in) |
| 1999 | 47.4 mm (1.9 in) |
| 2000 | 70.1 mm (2.8 in) |
| 2001 | 41.5 mm (1.6 in) |
| 2002 | 47.2 mm (1.9 in) |
| 2003 | 38.1 mm (1.5 in) |
| 2004 | 40.1 mm (1.6 in) |
| 2005 | 59.5 mm (2.3 in) |
| 2006 | 44.2 mm (1.7 in) |
| 2007 | 50.8 mm (2.0 in) |
| 2008 | 55.1 mm (2.2 in) |
| 2009 | 37.3 mm (1.5 in) |
| 2010 | 55.7 mm (2.2 in) |
| 2011 | 80.5 mm (3.2 in) |
| 2012 | 25.9 mm (1.0 in) |
| 2013 | 43.6 mm (1.7 in) |
| 2014 | 40.7 mm (1.6 in) |
| 2015 | 41.2 mm (1.6 in) |
| 2016 | 37.7 mm (1.5 in) |
| 2017 | 24.2 mm (1.0 in) |
| 2018 | 40.7 mm (1.6 in) |
| 2019 | 81.9 mm (3.2 in) |
| 2020 | 50.7 mm (2.0 in) |
| 2021 | 49.5 mm (1.9 in) |
| 2022 | 60.6 mm (2.4 in) |
| 2023 | 34.7 mm (1.4 in) |
| 2024 | 90.6 mm (3.6 in) |
| 2025 | 83.9 mm (3.3 in) |
| 2026 | 67.8 mm (2.7 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1937 | 48 days |
| 1938 | 32 days |
| 1939 | 34 days |
| 1940 | 24 days |
| 1941 | 26 days |
| 1942 | 25 days |
| 1943 | 42 days |
| 1944 | 40 days |
| 1945 | 25 days |
| 1946 | 30 days |
| 1947 | 20 days |
| 1948 | 37 days |
| 1949 | 50 days |
| 1950 | 19 days |
| 1951 | 33 days |
| 1952 | 47 days |
| 1953 | 47 days |
| 1954 | 34 days |
| 1955 | 36 days |
| 1956 | 32 days |
| 1957 | 19 days |
| 1958 | 27 days |
| 1959 | 46 days |
| 1960 | 77 days |
| 1961 | 37 days |
| 1962 | 25 days |
| 1963 | 63 days |
| 1964 | 48 days |
| 1965 | 57 days |
| 1966 | 61 days |
| 1967 | 25 days |
| 1968 | 37 days |
| 1969 | 62 days |
| 1970 | 32 days |
| 1971 | 39 days |
| 1972 | 61 days |
| 1973 | 64 days |
| 1974 | 37 days |
| 1975 | 60 days |
| 1976 | 64 days |
| 1977 | 39 days |
| 1978 | 39 days |
| 1979 | 36 days |
| 1980 | 49 days |
| 1981 | 49 days |
| 1982 | 44 days |
| 1983 | 55 days |
| 1984 | 54 days |
| 1985 | 47 days |
| 1987 | 47 days |
| 1988 | 49 days |
| 1989 | 31 days |
| 1990 | 52 days |
| 1991 | 42 days |
| 1992 | 40 days |
| 1993 | 23 days |
| 1994 | 32 days |
| 1995 | 18 days |
| 1996 | 21 days |
| 1997 | 57 days |
| 1998 | 26 days |
| 1999 | 24 days |
| 2000 | 38 days |
| 2001 | 73 days |
| 2002 | 27 days |
| 2003 | 29 days |
| 2004 | 44 days |
| 2005 | 35 days |
| 2006 | 32 days |
| 2007 | 33 days |
| 2008 | 35 days |
| 2009 | 64 days |
| 2010 | 29 days |
| 2011 | 25 days |
| 2012 | 32 days |
| 2013 | 15 days |
| 2014 | 22 days |
| 2015 | 36 days |
| 2016 | 34 days |
| 2017 | 23 days |
| 2018 | 22 days |
| 2019 | 46 days |
| 2020 | 47 days |
| 2021 | 37 days |
| 2022 | 45 days |
| 2023 | 42 days |
| 2024 | 35 days |
| 2025 | 27 days |
| 2026 | 32 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
63 years with a frostAcross 63 years with a frost, the median last spring frost at Westby falls on 16 May and the median first autumn frost on 18 September, which leaves a median of 125 days between them.
In 1976 to 2025 the median growing season was 126 days. That is 4 days more than in 1937 to 1972.
Fitted over all years, the growing season changes by +1.4 days per decade at this station.
| Measure | Median, all years | Earliest period (1937 to 1972) | Recent period (1976 to 2025) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 16 May | 19 May | 15 May | 4 days earlier | -0.3 days per decade |
| First autumn frost | 18 September | 18 September | 21 September | 3 days later | +1.1 days per decade |
| Growing days | 125 days | 122 days | 126 days | 4 days more | +1.4 days per decade |
A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.
Rainfall Return Levels
71 years, 1937 to 2025A day with at least 34.2 mm (1.3 in) of rain is expected about once in 2 years. A day with at least 92.8 mm (3.7 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 34.2 mm (1.3 in) | |
| 5 years | 46.7 mm (1.8 in) | |
| 10 years | 56.2 mm (2.2 in) | |
| 25 years | 69.5 mm (2.7 in) | |
| 50 years | 80.7 mm (3.2 in) | |
| 100 years | 92.8 mm (3.7 in) | Longer than the 71 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, 71 years of values from 1937 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: 114.3 mm (4.5 in) in 1990; 76.7 mm (3.0 in) in 1942; 73.7 mm (2.9 in) in 1953.
Station Changes
1 suspectedOne change was suspected in the annual mean temperature of Westby, at 1944. Each is measured against neighbouring stations.
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1944 ran 0.3 C (0.6 F) higher than in the years before (possible change).
| Year | Shift (C) | Shift (F) | Strength | Neighbours |
|---|---|---|---|---|
| 1944 | +0.3 | +0.6 | possible | 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
2001 to 2025 against 1961 to 1990Over 2001 to 2025, Westby had a mean temperature of 4.2 C (39.6 F) and 319.7 mm (12.6 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Max (United States, 235 km away), Wilton (United States, 308 km away) and Wishek (United States, 445 km away).
| Twin station | Country | Distance away | Mean temperature, 1961-1990 | Rain a year, 1961-1990 | Climate difference |
|---|---|---|---|---|---|
| Max | United States | 235 km (146 mi) | 4.2 C (39.6 F) | 420.7 mm (16.6 in) | 0.84 |
| Wilton | United States | 308 km (191 mi) | 4.5 C (40.1 F) | 444.3 mm (17.5 in) | 0.85 |
| Wishek | United States | 445 km (277 mi) | 4.3 C (39.8 F) | 447.7 mm (17.6 in) | 0.86 |
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 2026-10-13 (13 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-13).