Oconomowoc Wwtp Weather Records (USC00476200)
Record envelope, standing records and threshold days for Oconomowoc Wwtp (USC00476200), Wisconsin, United States, with 134 years of record.
Key Facts for Oconomowoc Wwtp
- Oconomowoc Wwtp (USC00476200) is a weather station in Wisconsin, United States at 43.10 latitude and -88.50 longitude, 262 m (858 ft) above sea level.
- The station reports from 1893 to 2026, 134 years of record.
- 1,464 records set at Oconomowoc Wwtp still stand.
- Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
- Oconomowoc Wwtp tied a daily record high maximum temperature of 28.3 C (82.9 F) on 11 October 2026 (provisional).
Provisional Records
Records set in the last 60 days are provisional until they clear the revision window.
About the Station
- Location: Wisconsin, United States, 43.10 latitude, -88.50 longitude.
- Elevation: 262 m (858 ft).
- Period of record: 1893 to 2026, 134 years.
- Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
7 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 15.0 C (59.0 F) | -36.1 C (-33.0 F) | 14.4 C (57.9 F) | -27.2 C (-17.0 F) |
| Feb | 22.2 C (72.0 F) | -33.9 C (-29.0 F) | 16.7 C (62.1 F) | -19.4 C (-2.9 F) |
| Mar | 28.3 C (82.9 F) | -28.3 C (-18.9 F) | 25.6 C (78.1 F) | -13.9 C (7.0 F) |
| Apr | 31.1 C (88.0 F) | -15.6 C (3.9 F) | 27.2 C (81.0 F) | -6.1 C (21.0 F) |
| May | 34.4 C (93.9 F) | -5.0 C (23.0 F) | 31.7 C (89.1 F) | -1.7 C (28.9 F) |
| Jun | 37.8 C (100.0 F) | -0.6 C (30.9 F) | 33.3 C (91.9 F) | 7.2 C (45.0 F) |
| Jul | 39.4 C (102.9 F) | 5.0 C (41.0 F) | 37.2 C (99.0 F) | 10.0 C (50.0 F) |
| Aug | 38.3 C (100.9 F) | 3.9 C (39.0 F) | 30.0 C (86.0 F) | 10.0 C (50.0 F) |
| Sep | 36.7 C (98.1 F) | -3.3 C (26.1 F) | 31.7 C (89.1 F) | 6.7 C (44.1 F) |
| Oct | 30.6 C (87.1 F) | -12.2 C (10.0 F) | 28.3 C (82.9 F) | 4.4 C (39.9 F) |
| Nov | 24.4 C (75.9 F) | -25.6 C (-14.1 F) | n/a | n/a |
| Dec | 19.4 C (66.9 F) | -31.7 C (-25.1 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1893 | 22 |
| 1894 | 31 |
| 1895 | 42 |
| 1896 | 19 |
| 1944 | 13 |
| 1945 | 31 |
| 1946 | 22 |
| 1947 | 29 |
| 1948 | 11 |
| 1949 | 13 |
| 1950 | 22 |
| 1951 | 19 |
| 1952 | 14 |
| 1953 | 21 |
| 1954 | 15 |
| 1955 | 10 |
| 1956 | 13 |
| 1957 | 7 |
| 1958 | 12 |
| 1959 | 26 |
| 1960 | 10 |
| 1961 | 2 |
| 1962 | 13 |
| 1963 | 33 |
| 1964 | 15 |
| 1965 | 22 |
| 1966 | 17 |
| 1967 | 19 |
| 1968 | 25 |
| 1969 | 12 |
| 1970 | 8 |
| 1971 | 5 |
| 1972 | 22 |
| 1973 | 14 |
| 1974 | 19 |
| 1975 | 16 |
| 1976 | 26 |
| 1977 | 21 |
| 1978 | 9 |
| 1979 | 14 |
| 1980 | 5 |
| 1981 | 15 |
| 1982 | 26 |
| 1983 | 30 |
| 1984 | 16 |
| 1985 | 18 |
| 1986 | 19 |
| 1987 | 15 |
| 1988 | 32 |
| 1989 | 24 |
| 1990 | 18 |
| 1991 | 22 |
| 1992 | 24 |
| 1993 | 11 |
| 1994 | 19 |
| 1995 | 16 |
| 1996 | 20 |
| 1997 | 9 |
| 1998 | 17 |
| 1999 | 12 |
| 2000 | 24 |
| 2001 | 13 |
| 2002 | 22 |
| 2003 | 5 |
| 2004 | 11 |
| 2005 | 13 |
| 2006 | 18 |
| 2007 | 17 |
| 2008 | 13 |
| 2009 | 14 |
| 2010 | 12 |
| 2011 | 12 |
| 2012 | 30 |
| 2013 | 7 |
| 2014 | 19 |
| 2015 | 11 |
| 2016 | 7 |
| 2017 | 21 |
| 2018 | 15 |
| 2019 | 14 |
| 2020 | 10 |
| 2021 | 11 |
| 2022 | 13 |
| 2023 | 11 |
| 2024 | 14 |
| 2025 | 13 |
| 2026 | 12 |
All-Time Record Progression
9 new records| Date | Kind | Detail |
|---|---|---|
| 1977-12-08 | Record daily snowfall | Record daily snowfall 29.2 cm (11.5 in) |
| 1979-01-24 | Record snow depth | Record snow depth 63.5 cm (25.0 in) |
| 1982-01-09 | Record low maximum temperature | Record low maximum temperature -23.9 C (-11.0 F) |
| 1988-08-17 | Record high maximum temperature | Record high maximum temperature 38.3 C (100.9 F) |
| 1994-01-19 | Record low maximum temperature | Record low maximum temperature -26.7 C (-16.1 F) |
| 1995-08-10 | Record daily precipitation | Record daily precipitation 136.7 mm (5.4 in) |
| 2012-07-05 | Record high maximum temperature | Record high maximum temperature 38.9 C (102.0 F) |
| 2012-07-06 | Record high maximum temperature | Record high maximum temperature 39.4 C (102.9 F) |
| 2024-01-13 | Record daily snowfall | Record daily snowfall 31.8 cm (12.5 in) |
Wettest Day of Each Month
Aug: 136.7 mm (5.4 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 33.5 mm (1.3 in) | 23 January 2018 |
| Feb | 35.8 mm (1.4 in) | 21 February 1997 |
| Mar | 64.3 mm (2.5 in) | 31 March 1998 |
| Apr | 60.2 mm (2.4 in) | 23 April 1999 |
| May | 71.6 mm (2.8 in) | 13 May 2014 |
| Jun | 90.4 mm (3.6 in) | 8 June 2008 |
| Jul | 122.4 mm (4.8 in) | 18 July 1952 |
| Aug | 136.7 mm (5.4 in) | 10 August 1995 |
| Sep | 126.5 mm (5.0 in) | 12 September 2022 |
| Oct | 71.6 mm (2.8 in) | 31 October 1984 |
| Nov | 60.5 mm (2.4 in) | 6 November 2005 |
| Dec | 41.7 mm (1.6 in) | 15 December 1971 |
Period of Record Coverage
1893 to 2026| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1893 | 352 | 96% | Yes |
| 1894 | 362 | 99% | Yes |
| 1895 | 358 | 98% | Yes |
| 1896 | 264 | 72% | No |
| 1944 | 179 | 49% | No |
| 1945 | 362 | 99% | Yes |
| 1946 | 365 | 100% | Yes |
| 1947 | 364 | 100% | Yes |
| 1948 | 363 | 99% | Yes |
| 1949 | 365 | 100% | Yes |
| 1950 | 365 | 100% | Yes |
| 1951 | 365 | 100% | Yes |
| 1952 | 366 | 100% | Yes |
| 1953 | 365 | 100% | Yes |
| 1954 | 365 | 100% | Yes |
| 1955 | 365 | 100% | Yes |
| 1956 | 366 | 100% | Yes |
| 1957 | 365 | 100% | Yes |
| 1958 | 363 | 99% | Yes |
| 1959 | 363 | 99% | Yes |
| 1960 | 366 | 100% | Yes |
| 1961 | 365 | 100% | Yes |
| 1962 | 365 | 100% | Yes |
| 1963 | 365 | 100% | Yes |
| 1964 | 365 | 100% | Yes |
| 1965 | 365 | 100% | Yes |
| 1966 | 365 | 100% | Yes |
| 1967 | 365 | 100% | Yes |
| 1968 | 365 | 100% | Yes |
| 1969 | 365 | 100% | Yes |
| 1970 | 364 | 100% | Yes |
| 1971 | 220 | 60% | No |
| 1972 | 365 | 100% | Yes |
| 1973 | 363 | 99% | Yes |
| 1974 | 364 | 100% | Yes |
| 1975 | 364 | 100% | Yes |
| 1976 | 366 | 100% | Yes |
| 1977 | 363 | 99% | Yes |
| 1978 | 361 | 99% | Yes |
| 1979 | 362 | 99% | Yes |
| 1980 | 363 | 99% | Yes |
| 1981 | 362 | 99% | Yes |
| 1982 | 343 | 94% | Yes |
| 1983 | 365 | 100% | Yes |
| 1984 | 366 | 100% | Yes |
| 1985 | 363 | 99% | Yes |
| 1986 | 365 | 100% | Yes |
| 1987 | 365 | 100% | Yes |
| 1988 | 366 | 100% | Yes |
| 1989 | 365 | 100% | Yes |
| 1990 | 362 | 99% | Yes |
| 1991 | 365 | 100% | Yes |
| 1992 | 366 | 100% | Yes |
| 1993 | 365 | 100% | Yes |
| 1994 | 365 | 100% | Yes |
| 1995 | 365 | 100% | Yes |
| 1996 | 366 | 100% | Yes |
| 1997 | 365 | 100% | Yes |
| 1998 | 365 | 100% | Yes |
| 1999 | 365 | 100% | Yes |
| 2000 | 366 | 100% | Yes |
| 2001 | 365 | 100% | Yes |
| 2002 | 365 | 100% | Yes |
| 2003 | 365 | 100% | Yes |
| 2004 | 366 | 100% | Yes |
| 2005 | 365 | 100% | Yes |
| 2006 | 365 | 100% | Yes |
| 2007 | 364 | 100% | Yes |
| 2008 | 365 | 100% | Yes |
| 2009 | 365 | 100% | Yes |
| 2010 | 365 | 100% | Yes |
| 2011 | 365 | 100% | Yes |
| 2012 | 366 | 100% | Yes |
| 2013 | 365 | 100% | Yes |
| 2014 | 365 | 100% | Yes |
| 2015 | 365 | 100% | Yes |
| 2016 | 365 | 100% | Yes |
| 2017 | 359 | 98% | Yes |
| 2018 | 364 | 100% | Yes |
| 2019 | 320 | 88% | No |
| 2020 | 351 | 96% | Yes |
| 2021 | 364 | 100% | Yes |
| 2022 | 364 | 100% | Yes |
| 2023 | 352 | 96% | Yes |
| 2024 | 365 | 100% | Yes |
| 2025 | 365 | 100% | Yes |
| 2026 | 285 | 78% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 11 October 2026 | Oconomowoc Wwtp, US | daily high max (Tie, Provisional) | 28.3 C (82.9 F) | tie | 16 years | 3 of 100 (Routine) |
| 19 September 2026 | Oconomowoc Wwtp, US | daily rain (Provisional) | 63.5 mm (2.5 in) | 11.4 mm (0.4 in) | 65 years | 37 of 100 (Notable) |
| 1 August 2026 | Oconomowoc Wwtp, US | daily rain | 95.3 mm (3.8 in) | 58.2 mm (2.3 in) | 80 years | 74 of 100 (Major) |
| 16 July 2026 | Oconomowoc Wwtp, US | daily high max | 37.2 C (99.0 F) | 1.6 C (2.9 F) | 13 years | 18 of 100 (Routine) |
| 30 June 2026 | Oconomowoc Wwtp, US | monthly high min (Tie) | 25.6 C (78.1 F) | tie | 1 year | 5 of 100 (Routine) |
| 16 April 2026 | Oconomowoc Wwtp, US | daily rain | 35.3 mm (1.4 in) | 9.6 mm (0.38 in) | 28 years | 28 of 100 (Routine) |
| 14 April 2026 | Oconomowoc Wwtp, US | daily high min | 13.3 C (55.9 F) | 0.5 C (0.9 F) | 65 years | 30 of 100 (Routine) |
| 13 April 2026 | Oconomowoc Wwtp, US | daily rain | 21.1 mm (0.8 in) | 0.8 mm (0.03 in) | 39 years | 20 of 100 (Routine) |
| 13 April 2026 | Oconomowoc Wwtp, US | daily high min | 13.9 C (57.0 F) | 1.1 C (2.0 F) | 3 years | 12 of 100 (Routine) |
| 17 March 2026 | Oconomowoc Wwtp, US | daily low max (Tie) | -4.4 C (24.1 F) | tie | 36 years | 5 of 100 (Routine) |
| 16 March 2026 | Oconomowoc Wwtp, US | daily rain | 45.7 mm (1.8 in) | 27.9 mm (1.1 in) | 9 years | 52 of 100 (Notable) |
| 16 March 2026 | Oconomowoc Wwtp, US | daily snowfall | 15.2 cm (6.0 in) | 8.8 cm (3.5 in) | 65 years | 48 of 100 (Notable) |
| 10 March 2026 | Oconomowoc Wwtp, US | daily high max | 21.7 C (71.1 F) | 2.3 C (4.1 F) | 131 years | 43 of 100 (Notable) |
| 17 February 2026 | Oconomowoc Wwtp, US | daily high max | 16.7 C (62.1 F) | 2.3 C (4.1 F) | 44 years | 26 of 100 (Routine) |
| 17 February 2026 | Oconomowoc Wwtp, US | daily high min (Tie) | 2.8 C (37.0 F) | tie | 28 years | 4 of 100 (Routine) |
| 25 January 2026 | Oconomowoc Wwtp, US | daily low max | -16.7 C (1.9 F) | 1.1 C (2.0 F) | 63 years | 29 of 100 (Routine) |
| 24 January 2026 | Oconomowoc Wwtp, US | daily low max | -21.7 C (-7.1 F) | 5.0 C (9.0 F) | 60 years | 35 of 100 (Notable) |
| 24 January 2026 | Oconomowoc Wwtp, US | daily low min | -27.2 C (-17.0 F) | 0.5 C (0.9 F) | 63 years | 28 of 100 (Routine) |
| 14 January 2026 | Oconomowoc Wwtp, US | daily high max | 11.7 C (53.1 F) | 3.4 C (6.1 F) | 74 years | 37 of 100 (Notable) |
| 9 January 2026 | Oconomowoc Wwtp, US | daily high max | 14.4 C (57.9 F) | 2.7 C (4.9 F) | 23 years | 20 of 100 (Routine) |
Climate Trend
79 complete years, 1893 to 2025| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1893 | 6.7 C | -1.50 C |
| 1894 | 9.0 C | +0.77 C |
| 1895 | 7.5 C | -0.69 C |
| 1945 | 7.8 C | -0.42 C |
| 1946 | 9.4 C | +1.16 C |
| 1947 | 7.9 C | -0.28 C |
| 1948 | 8.2 C | -0.03 C |
| 1949 | 8.7 C | +0.45 C |
| 1950 | 6.8 C | -1.40 C |
| 1951 | 6.8 C | -1.46 C |
| 1952 | 8.5 C | +0.32 C |
| 1953 | 9.3 C | +1.06 C |
| 1954 | 8.8 C | +0.62 C |
| 1955 | 8.7 C | +0.49 C |
| 1956 | 8.5 C | +0.27 C |
| 1957 | 8.3 C | +0.08 C |
| 1958 | 8.0 C | -0.21 C |
| 1959 | 8.0 C | -0.18 C |
| 1960 | 7.8 C | -0.38 C |
| 1961 | 8.5 C | +0.29 C |
| 1962 | 7.9 C | -0.32 C |
| 1963 | 7.9 C | -0.34 C |
| 1964 | 9.1 C | +0.88 C |
| 1965 | 8.1 C | -0.11 C |
| 1966 | 7.8 C | -0.39 C |
| 1967 | 7.7 C | -0.53 C |
| 1968 | 8.7 C | +0.46 C |
| 1969 | 7.8 C | -0.39 C |
| 1970 | 8.3 C | +0.03 C |
| 1972 | 6.7 C | -1.48 C |
| 1973 | 9.5 C | +1.26 C |
| 1974 | 7.3 C | -0.89 C |
| 1975 | 7.8 C | -0.39 C |
| 1976 | 7.0 C | -1.27 C |
| 1977 | 7.8 C | -0.43 C |
| 1978 | 6.9 C | -1.36 C |
| 1979 | 7.3 C | -0.89 C |
| 1980 | 8.7 C | +0.52 C |
| 1981 | 8.0 C | -0.24 C |
| 1983 | 7.9 C | -0.28 C |
| 1984 | 8.0 C | -0.24 C |
| 1985 | 7.3 C | -0.89 C |
| 1986 | 8.2 C | +0.01 C |
| 1987 | 9.5 C | +1.27 C |
| 1988 | 8.2 C | 0.00 C |
| 1989 | 6.9 C | -1.31 C |
| 1990 | 8.8 C | +0.54 C |
| 1991 | 8.6 C | +0.33 C |
| 1992 | 7.7 C | -0.48 C |
| 1993 | 7.4 C | -0.85 C |
| 1994 | 7.8 C | -0.44 C |
| 1995 | 7.7 C | -0.54 C |
| 1996 | 6.7 C | -1.55 C |
| 1997 | 7.6 C | -0.61 C |
| 1998 | 10.2 C | +1.99 C |
| 1999 | 9.1 C | +0.85 C |
| 2000 | 8.4 C | +0.16 C |
| 2001 | 9.0 C | +0.74 C |
| 2002 | 8.8 C | +0.58 C |
| 2003 | 7.9 C | -0.35 C |
| 2004 | 8.3 C | +0.05 C |
| 2005 | 8.9 C | +0.72 C |
| 2006 | 9.0 C | +0.81 C |
| 2007 | 8.6 C | +0.36 C |
| 2008 | 7.4 C | -0.80 C |
| 2009 | 7.6 C | -0.64 C |
| 2010 | 9.1 C | +0.86 C |
| 2011 | 8.4 C | +0.21 C |
| 2012 | 10.4 C | +2.18 C |
| 2013 | 7.3 C | -0.96 C |
| 2014 | 6.5 C | -1.76 C |
| 2015 | 8.6 C | +0.39 C |
| 2017 | 9.2 C | +0.95 C |
| 2018 | 8.1 C | -0.08 C |
| 2021 | 9.2 C | +1.00 C |
| 2022 | 8.1 C | -0.11 C |
| 2023 | 10.1 C | +1.88 C |
| 2024 | 10.6 C | +2.33 C |
| 2025 | 9.0 C | +0.81 C |
The annual mean temperature here has risen by 0.07 C (0.01 to 0.14) per decade over 1893 to 2025. In Fahrenheit: 0.13 F (0.01 to 0.26) per decade. The slope is a straight line fitted to 79 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.07 C (0.01 to 0.14) per decade | 0.13 F (0.01 to 0.26) per decade | 1893 to 2025 | 79 | Rise |
| Mean daily maximum | 0.04 C (-0.04 to 0.11) per decade | 0.1 F (-0.1 to 0.2) per decade | 1893 to 2025 | 79 | Not clearly different from zero |
| Mean daily minimum | 0.11 C (0.04 to 0.18) per decade | 0.2 F (0.1 to 0.3) per decade | 1893 to 2025 | 79 | 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
1893 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 39.4 C (102.9 F) | 2012 | 34.4 C (93.9 F) | 87 |
| Coldest night (TNn) | -36.1 C (-33.0 F) | 1951 | -26.1 C (-15.0 F) | 87 |
| Wettest day (Rx1day) | 136.7 mm (5.4 in) | 1995 | 56.6 mm (2.2 in) | 87 |
| Wettest five days (Rx5day) | 211.3 mm (8.3 in) | 2008 | 87.1 mm (3.4 in) | 87 |
| Longest dry spell (CDD) | 40 days | 1995 | 21 days | 87 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1893 | 35.0 C (95.0 F) |
| 1894 | 37.8 C (100.0 F) |
| 1895 | 35.0 C (95.0 F) |
| 1896 | 35.0 C (95.0 F) |
| 1944 | 35.6 C (96.1 F) |
| 1945 | 36.7 C (98.1 F) |
| 1946 | 36.7 C (98.1 F) |
| 1947 | 37.2 C (99.0 F) |
| 1948 | 36.7 C (98.1 F) |
| 1949 | 35.6 C (96.1 F) |
| 1950 | 31.7 C (89.1 F) |
| 1951 | 32.2 C (90.0 F) |
| 1952 | 35.0 C (95.0 F) |
| 1953 | 36.7 C (98.1 F) |
| 1954 | 34.4 C (93.9 F) |
| 1955 | 36.1 C (97.0 F) |
| 1956 | 34.4 C (93.9 F) |
| 1957 | 33.9 C (93.0 F) |
| 1958 | 33.3 C (91.9 F) |
| 1959 | 34.4 C (93.9 F) |
| 1960 | 33.9 C (93.0 F) |
| 1961 | 33.9 C (93.0 F) |
| 1962 | 33.9 C (93.0 F) |
| 1963 | 37.2 C (99.0 F) |
| 1964 | 36.7 C (98.1 F) |
| 1965 | 37.2 C (99.0 F) |
| 1966 | 37.2 C (99.0 F) |
| 1967 | 32.8 C (91.0 F) |
| 1968 | 34.4 C (93.9 F) |
| 1969 | 32.8 C (91.0 F) |
| 1970 | 34.4 C (93.9 F) |
| 1971 | 28.9 C (84.0 F) |
| 1972 | 34.4 C (93.9 F) |
| 1973 | 36.7 C (98.1 F) |
| 1974 | 35.0 C (95.0 F) |
| 1975 | 34.4 C (93.9 F) |
| 1976 | 37.8 C (100.0 F) |
| 1977 | 35.6 C (96.1 F) |
| 1978 | 34.4 C (93.9 F) |
| 1979 | 31.7 C (89.1 F) |
| 1980 | 35.6 C (96.1 F) |
| 1981 | 34.4 C (93.9 F) |
| 1982 | 33.3 C (91.9 F) |
| 1983 | 36.1 C (97.0 F) |
| 1984 | 35.6 C (96.1 F) |
| 1985 | 35.0 C (95.0 F) |
| 1986 | 33.3 C (91.9 F) |
| 1987 | 36.7 C (98.1 F) |
| 1988 | 38.3 C (100.9 F) |
| 1989 | 34.4 C (93.9 F) |
| 1990 | 33.9 C (93.0 F) |
| 1991 | 33.9 C (93.0 F) |
| 1992 | 33.3 C (91.9 F) |
| 1993 | 31.7 C (89.1 F) |
| 1994 | 35.6 C (96.1 F) |
| 1995 | 37.8 C (100.0 F) |
| 1996 | 33.3 C (91.9 F) |
| 1997 | 32.8 C (91.0 F) |
| 1998 | 32.8 C (91.0 F) |
| 1999 | 35.0 C (95.0 F) |
| 2000 | 33.9 C (93.0 F) |
| 2001 | 35.0 C (95.0 F) |
| 2002 | 36.1 C (97.0 F) |
| 2003 | 33.9 C (93.0 F) |
| 2004 | 31.7 C (89.1 F) |
| 2005 | 34.4 C (93.9 F) |
| 2006 | 35.0 C (95.0 F) |
| 2007 | 32.8 C (91.0 F) |
| 2008 | 33.3 C (91.9 F) |
| 2009 | 35.0 C (95.0 F) |
| 2010 | 33.3 C (91.9 F) |
| 2011 | 35.0 C (95.0 F) |
| 2012 | 39.4 C (102.9 F) |
| 2013 | 33.9 C (93.0 F) |
| 2014 | 32.2 C (90.0 F) |
| 2015 | 33.9 C (93.0 F) |
| 2016 | 32.8 C (91.0 F) |
| 2017 | 33.9 C (93.0 F) |
| 2018 | 33.9 C (93.0 F) |
| 2019 | 30.0 C (86.0 F) |
| 2020 | 33.3 C (91.9 F) |
| 2021 | 35.0 C (95.0 F) |
| 2022 | 35.6 C (96.1 F) |
| 2023 | 36.1 C (97.0 F) |
| 2024 | 33.3 C (91.9 F) |
| 2025 | 33.9 C (93.0 F) |
| 2026 | 37.2 C (99.0 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1893 | -32.8 C (-27.0 F) |
| 1894 | -28.3 C (-18.9 F) |
| 1895 | -32.8 C (-27.0 F) |
| 1896 | -25.6 C (-14.1 F) |
| 1944 | -26.1 C (-15.0 F) |
| 1945 | -27.2 C (-17.0 F) |
| 1946 | -25.0 C (-13.0 F) |
| 1947 | -26.7 C (-16.1 F) |
| 1948 | -31.7 C (-25.1 F) |
| 1949 | -27.2 C (-17.0 F) |
| 1950 | -29.4 C (-20.9 F) |
| 1951 | -36.1 C (-33.0 F) |
| 1952 | -24.4 C (-11.9 F) |
| 1953 | -22.2 C (-8.0 F) |
| 1954 | -26.7 C (-16.1 F) |
| 1955 | -25.0 C (-13.0 F) |
| 1956 | -23.9 C (-11.0 F) |
| 1957 | -23.9 C (-11.0 F) |
| 1958 | -25.0 C (-13.0 F) |
| 1959 | -31.1 C (-24.0 F) |
| 1960 | -25.0 C (-13.0 F) |
| 1961 | -23.9 C (-11.0 F) |
| 1962 | -28.3 C (-18.9 F) |
| 1963 | -32.2 C (-26.0 F) |
| 1964 | -21.1 C (-6.0 F) |
| 1965 | -28.9 C (-20.0 F) |
| 1966 | -31.1 C (-24.0 F) |
| 1967 | -29.4 C (-20.9 F) |
| 1968 | -28.9 C (-20.0 F) |
| 1969 | -25.6 C (-14.1 F) |
| 1970 | -28.9 C (-20.0 F) |
| 1971 | -28.9 C (-20.0 F) |
| 1972 | -31.1 C (-24.0 F) |
| 1973 | -23.3 C (-9.9 F) |
| 1974 | -27.2 C (-17.0 F) |
| 1975 | -25.0 C (-13.0 F) |
| 1976 | -30.0 C (-22.0 F) |
| 1977 | -29.4 C (-20.9 F) |
| 1978 | -25.0 C (-13.0 F) |
| 1979 | -30.0 C (-22.0 F) |
| 1980 | -22.8 C (-9.0 F) |
| 1981 | -25.0 C (-13.0 F) |
| 1982 | -32.8 C (-27.0 F) |
| 1983 | -31.7 C (-25.1 F) |
| 1984 | -31.1 C (-24.0 F) |
| 1985 | -33.9 C (-29.0 F) |
| 1986 | -27.8 C (-18.0 F) |
| 1987 | -24.4 C (-11.9 F) |
| 1988 | -27.2 C (-17.0 F) |
| 1989 | -28.3 C (-18.9 F) |
| 1990 | -23.3 C (-9.9 F) |
| 1991 | -25.6 C (-14.1 F) |
| 1992 | -22.2 C (-8.0 F) |
| 1993 | -24.4 C (-11.9 F) |
| 1994 | -32.8 C (-27.0 F) |
| 1995 | -22.2 C (-8.0 F) |
| 1996 | -33.9 C (-29.0 F) |
| 1997 | -26.1 C (-15.0 F) |
| 1998 | -22.2 C (-8.0 F) |
| 1999 | -30.0 C (-22.0 F) |
| 2000 | -30.0 C (-22.0 F) |
| 2001 | -23.9 C (-11.0 F) |
| 2002 | -25.0 C (-13.0 F) |
| 2003 | -22.8 C (-9.0 F) |
| 2004 | -26.1 C (-15.0 F) |
| 2005 | -22.8 C (-9.0 F) |
| 2006 | -27.2 C (-17.0 F) |
| 2007 | -27.2 C (-17.0 F) |
| 2008 | -25.0 C (-13.0 F) |
| 2009 | -31.1 C (-24.0 F) |
| 2010 | -22.2 C (-8.0 F) |
| 2011 | -27.8 C (-18.0 F) |
| 2012 | -21.1 C (-6.0 F) |
| 2013 | -24.4 C (-11.9 F) |
| 2014 | -28.3 C (-18.9 F) |
| 2015 | -25.6 C (-14.1 F) |
| 2016 | -22.2 C (-8.0 F) |
| 2017 | -21.7 C (-7.1 F) |
| 2018 | -24.4 C (-11.9 F) |
| 2019 | -34.4 C (-29.9 F) |
| 2020 | -25.6 C (-14.1 F) |
| 2021 | -25.0 C (-13.0 F) |
| 2022 | -27.8 C (-18.0 F) |
| 2023 | -23.3 C (-9.9 F) |
| 2024 | -22.8 C (-9.0 F) |
| 2025 | -24.4 C (-11.9 F) |
| 2026 | -27.2 C (-17.0 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1893 | 57.7 mm (2.3 in) |
| 1894 | 76.5 mm (3.0 in) |
| 1895 | 25.4 mm (1.0 in) |
| 1896 | 43.2 mm (1.7 in) |
| 1944 | 36.3 mm (1.4 in) |
| 1945 | 51.3 mm (2.0 in) |
| 1946 | 53.8 mm (2.1 in) |
| 1947 | 69.9 mm (2.8 in) |
| 1948 | 33.8 mm (1.3 in) |
| 1949 | 47.5 mm (1.9 in) |
| 1950 | 86.1 mm (3.4 in) |
| 1951 | 59.9 mm (2.4 in) |
| 1952 | 122.4 mm (4.8 in) |
| 1953 | 49.8 mm (2.0 in) |
| 1954 | 37.6 mm (1.5 in) |
| 1955 | 116.8 mm (4.6 in) |
| 1956 | 47.2 mm (1.9 in) |
| 1957 | 39.9 mm (1.6 in) |
| 1958 | 71.4 mm (2.8 in) |
| 1959 | 40.6 mm (1.6 in) |
| 1960 | 52.1 mm (2.1 in) |
| 1961 | 87.6 mm (3.4 in) |
| 1962 | 48.8 mm (1.9 in) |
| 1963 | 23.6 mm (0.9 in) |
| 1964 | 53.8 mm (2.1 in) |
| 1965 | 66.3 mm (2.6 in) |
| 1966 | 36.8 mm (1.4 in) |
| 1967 | 44.2 mm (1.7 in) |
| 1968 | 82.6 mm (3.3 in) |
| 1969 | 49.8 mm (2.0 in) |
| 1970 | 51.1 mm (2.0 in) |
| 1971 | 41.7 mm (1.6 in) |
| 1972 | 84.6 mm (3.3 in) |
| 1973 | 38.6 mm (1.5 in) |
| 1974 | 48.3 mm (1.9 in) |
| 1975 | 55.4 mm (2.2 in) |
| 1976 | 44.5 mm (1.8 in) |
| 1977 | 77.0 mm (3.0 in) |
| 1978 | 74.2 mm (2.9 in) |
| 1979 | 44.2 mm (1.7 in) |
| 1980 | 54.9 mm (2.2 in) |
| 1981 | 54.1 mm (2.1 in) |
| 1982 | 57.2 mm (2.3 in) |
| 1983 | 34.3 mm (1.4 in) |
| 1984 | 71.6 mm (2.8 in) |
| 1985 | 70.9 mm (2.8 in) |
| 1986 | 80.8 mm (3.2 in) |
| 1987 | 44.2 mm (1.7 in) |
| 1988 | 37.3 mm (1.5 in) |
| 1989 | 67.1 mm (2.6 in) |
| 1990 | 52.6 mm (2.1 in) |
| 1991 | 99.3 mm (3.9 in) |
| 1992 | 38.1 mm (1.5 in) |
| 1993 | 73.7 mm (2.9 in) |
| 1994 | 50.5 mm (2.0 in) |
| 1995 | 136.7 mm (5.4 in) |
| 1996 | 67.1 mm (2.6 in) |
| 1997 | 55.9 mm (2.2 in) |
| 1998 | 64.3 mm (2.5 in) |
| 1999 | 60.2 mm (2.4 in) |
| 2000 | 72.6 mm (2.9 in) |
| 2001 | 63.2 mm (2.5 in) |
| 2002 | 40.4 mm (1.6 in) |
| 2003 | 56.9 mm (2.2 in) |
| 2004 | 95.0 mm (3.7 in) |
| 2005 | 60.5 mm (2.4 in) |
| 2006 | 54.6 mm (2.1 in) |
| 2007 | 53.8 mm (2.1 in) |
| 2008 | 90.4 mm (3.6 in) |
| 2009 | 49.0 mm (1.9 in) |
| 2010 | 104.4 mm (4.1 in) |
| 2011 | 33.3 mm (1.3 in) |
| 2012 | 39.1 mm (1.5 in) |
| 2013 | 74.4 mm (2.9 in) |
| 2014 | 71.6 mm (2.8 in) |
| 2015 | 62.2 mm (2.4 in) |
| 2016 | 71.6 mm (2.8 in) |
| 2017 | 70.4 mm (2.8 in) |
| 2018 | 76.2 mm (3.0 in) |
| 2019 | 64.0 mm (2.5 in) |
| 2020 | 68.6 mm (2.7 in) |
| 2021 | 56.6 mm (2.2 in) |
| 2022 | 126.5 mm (5.0 in) |
| 2023 | 56.1 mm (2.2 in) |
| 2024 | 43.2 mm (1.7 in) |
| 2025 | 101.6 mm (4.0 in) |
| 2026 | 95.3 mm (3.8 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1893 | 82.8 mm (3.3 in) |
| 1894 | 99.6 mm (3.9 in) |
| 1895 | 43.5 mm (1.7 in) |
| 1896 | 85.9 mm (3.4 in) |
| 1944 | 48.2 mm (1.9 in) |
| 1945 | 67.3 mm (2.6 in) |
| 1946 | 62.5 mm (2.5 in) |
| 1947 | 75.0 mm (3.0 in) |
| 1948 | 61.2 mm (2.4 in) |
| 1949 | 57.9 mm (2.3 in) |
| 1950 | 142.0 mm (5.6 in) |
| 1951 | 114.5 mm (4.5 in) |
| 1952 | 145.2 mm (5.7 in) |
| 1953 | 104.9 mm (4.1 in) |
| 1954 | 92.1 mm (3.6 in) |
| 1955 | 117.8 mm (4.6 in) |
| 1956 | 88.4 mm (3.5 in) |
| 1957 | 57.2 mm (2.3 in) |
| 1958 | 87.9 mm (3.5 in) |
| 1959 | 65.0 mm (2.6 in) |
| 1960 | 85.6 mm (3.4 in) |
| 1961 | 147.3 mm (5.8 in) |
| 1962 | 84.9 mm (3.3 in) |
| 1963 | 36.8 mm (1.4 in) |
| 1964 | 75.4 mm (3.0 in) |
| 1965 | 115.3 mm (4.5 in) |
| 1966 | 53.4 mm (2.1 in) |
| 1967 | 119.7 mm (4.7 in) |
| 1968 | 85.1 mm (3.4 in) |
| 1969 | 91.2 mm (3.6 in) |
| 1970 | 76.7 mm (3.0 in) |
| 1971 | 49.7 mm (2.0 in) |
| 1972 | 140.5 mm (5.5 in) |
| 1973 | 53.6 mm (2.1 in) |
| 1974 | 65.1 mm (2.6 in) |
| 1975 | 87.1 mm (3.4 in) |
| 1976 | 53.1 mm (2.1 in) |
| 1977 | 138.3 mm (5.4 in) |
| 1978 | 106.0 mm (4.2 in) |
| 1979 | 68.0 mm (2.7 in) |
| 1980 | 116.7 mm (4.6 in) |
| 1981 | 71.6 mm (2.8 in) |
| 1982 | 95.0 mm (3.7 in) |
| 1983 | 45.9 mm (1.8 in) |
| 1984 | 86.8 mm (3.4 in) |
| 1985 | 86.5 mm (3.4 in) |
| 1986 | 118.9 mm (4.7 in) |
| 1987 | 68.4 mm (2.7 in) |
| 1988 | 93.4 mm (3.7 in) |
| 1989 | 71.4 mm (2.8 in) |
| 1990 | 74.7 mm (2.9 in) |
| 1991 | 136.4 mm (5.4 in) |
| 1992 | 84.5 mm (3.3 in) |
| 1993 | 83.4 mm (3.3 in) |
| 1994 | 96.2 mm (3.8 in) |
| 1995 | 161.6 mm (6.4 in) |
| 1996 | 85.1 mm (3.4 in) |
| 1997 | 76.5 mm (3.0 in) |
| 1998 | 134.6 mm (5.3 in) |
| 1999 | 93.7 mm (3.7 in) |
| 2000 | 112.5 mm (4.4 in) |
| 2001 | 87.7 mm (3.5 in) |
| 2002 | 62.4 mm (2.5 in) |
| 2003 | 98.5 mm (3.9 in) |
| 2004 | 101.6 mm (4.0 in) |
| 2005 | 61.8 mm (2.4 in) |
| 2006 | 96.5 mm (3.8 in) |
| 2007 | 127.6 mm (5.0 in) |
| 2008 | 211.3 mm (8.3 in) |
| 2009 | 69.7 mm (2.7 in) |
| 2010 | 130.1 mm (5.1 in) |
| 2011 | 61.3 mm (2.4 in) |
| 2012 | 67.1 mm (2.6 in) |
| 2013 | 90.7 mm (3.6 in) |
| 2014 | 94.5 mm (3.7 in) |
| 2015 | 114.0 mm (4.5 in) |
| 2016 | 74.4 mm (2.9 in) |
| 2017 | 119.4 mm (4.7 in) |
| 2018 | 131.3 mm (5.2 in) |
| 2019 | 112.0 mm (4.4 in) |
| 2020 | 84.6 mm (3.3 in) |
| 2021 | 154.9 mm (6.1 in) |
| 2022 | 158.5 mm (6.2 in) |
| 2023 | 71.0 mm (2.8 in) |
| 2024 | 81.7 mm (3.2 in) |
| 2025 | 203.0 mm (8.0 in) |
| 2026 | 133.4 mm (5.3 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1893 | 21 days |
| 1894 | 25 days |
| 1895 | 22 days |
| 1896 | 19 days |
| 1944 | 26 days |
| 1945 | 16 days |
| 1946 | 29 days |
| 1947 | 25 days |
| 1948 | 20 days |
| 1949 | 20 days |
| 1950 | 30 days |
| 1951 | 18 days |
| 1952 | 30 days |
| 1953 | 24 days |
| 1954 | 19 days |
| 1955 | 19 days |
| 1956 | 25 days |
| 1957 | 28 days |
| 1958 | 31 days |
| 1959 | 28 days |
| 1960 | 30 days |
| 1961 | 22 days |
| 1962 | 14 days |
| 1963 | 18 days |
| 1964 | 24 days |
| 1965 | 19 days |
| 1966 | 25 days |
| 1967 | 19 days |
| 1968 | 22 days |
| 1969 | 24 days |
| 1970 | 22 days |
| 1971 | 15 days |
| 1972 | 24 days |
| 1973 | 18 days |
| 1974 | 14 days |
| 1975 | 19 days |
| 1976 | 26 days |
| 1977 | 17 days |
| 1978 | 24 days |
| 1979 | 29 days |
| 1980 | 18 days |
| 1981 | 25 days |
| 1982 | 25 days |
| 1983 | 17 days |
| 1984 | 21 days |
| 1985 | 14 days |
| 1986 | 23 days |
| 1987 | 29 days |
| 1988 | 37 days |
| 1989 | 21 days |
| 1990 | 15 days |
| 1991 | 28 days |
| 1992 | 15 days |
| 1993 | 18 days |
| 1994 | 14 days |
| 1995 | 40 days |
| 1996 | 18 days |
| 1997 | 15 days |
| 1998 | 19 days |
| 1999 | 25 days |
| 2000 | 15 days |
| 2001 | 19 days |
| 2002 | 15 days |
| 2003 | 22 days |
| 2004 | 19 days |
| 2005 | 18 days |
| 2006 | 16 days |
| 2007 | 25 days |
| 2008 | 14 days |
| 2009 | 26 days |
| 2010 | 29 days |
| 2011 | 16 days |
| 2012 | 26 days |
| 2013 | 14 days |
| 2014 | 14 days |
| 2015 | 26 days |
| 2016 | 15 days |
| 2017 | 25 days |
| 2018 | 20 days |
| 2019 | 27 days |
| 2020 | 20 days |
| 2021 | 21 days |
| 2022 | 20 days |
| 2023 | 14 days |
| 2024 | 22 days |
| 2025 | 22 days |
| 2026 | 24 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
79 years with a frostAcross 79 years with a frost, the median last spring frost at Oconomowoc Wwtp falls on 2 May and the median first autumn frost on 6 October, which leaves a median of 159 days between them.
In 1993 to 2025 the median growing season was 163 days. That is 5 days more than in 1893 to 1972.
Fitted over all years, the growing season changes by +1.9 days per decade at this station.
| Measure | Median, all years | Earliest period (1893 to 1972) | Recent period (1993 to 2025) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 2 May | 6 May | 28 April | 8 days earlier | -0.8 days per decade |
| First autumn frost | 6 October | 6 October | 11 October | 5 days later | +1.1 days per decade |
| Growing days | 159 days | 158 days | 163 days | 5 days more | +1.9 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
83 years, 1893 to 2025A day with at least 58.2 mm (2.3 in) of rain is expected about once in 2 years. A day with at least 137.0 mm (5.4 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 58.2 mm (2.3 in) | |
| 5 years | 78.1 mm (3.1 in) | |
| 10 years | 91.8 mm (3.6 in) | |
| 25 years | 109.6 mm (4.3 in) | |
| 50 years | 123.1 mm (4.8 in) | |
| 100 years | 137.0 mm (5.4 in) | Longer than the 83 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, 83 years of values from 1893 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: 136.7 mm (5.4 in) in 1995; 126.5 mm (5.0 in) in 2022; 122.4 mm (4.8 in) in 1952.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Climate Twins
2008 to 2025 against 1961 to 1990Over 2008 to 2025, Oconomowoc Wwtp had a mean temperature of 8.6 C (47.6 F) and 947.9 mm (37.3 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Angola (United States, 328 km away), Whitehall (United States, 1,221 km away) and Lagrange (United States, 301 km away).
| Twin station | Country | Distance away | Mean temperature, 1961-1990 | Rain a year, 1961-1990 | Climate difference |
|---|---|---|---|---|---|
| Angola | United States | 328 km (204 mi) | 8.5 C (47.3 F) | 905.2 mm (35.6 in) | 0.56 |
| Whitehall | United States | 1,221 km (759 mi) | 8.4 C (47.1 F) | 959.5 mm (37.8 in) | 0.60 |
| Lagrange | United States | 301 km (187 mi) | 8.8 C (47.8 F) | 927.0 mm (36.5 in) | 0.63 |
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 2026-10-14 (14 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-14).