Jefferson County, MT
An ordinary day in Jefferson County, MT: was cooler than 42 of 75 earlier years in the county average (county average from NOAA gridded data, 1951 to 2026).
Last updated . This page normally updates every day; the latest update is late.
- High
- 62.2°F
- Coldest since 2023
- 34th coldest of 76
- Low
- 36.2°F
- Warmest since 2025
- 33rd warmest of 76
No measurable precipitation in the county average of Jefferson County, MT for 6 days to Tuesday 29 September 2026 (county average from NOAA gridded data, 1951 to 2026).
- Normal range, 49.9 to 71.8°F
Every year as a table
Every 29 September low of the county average in Jefferson County, MT since 1951: 36.2°F in 2026; the lowest is 15.4°F, in 1985.
| Year | High, °F | Low, °F |
|---|---|---|
| 2026 | 62.2 | 36.2 |
| 2025 | 76.1 | 42.6 |
| 2024 | 79 | 40.8 |
| 2023 | 57.7 | 31.8 |
| 2022 | 78.5 | 45.2 |
| 2021 | 59.2 | 32.1 |
| 2020 | 66.9 | 31.8 |
| 2019 | 35.5 | 22.8 |
| 2018 | 48 | 32.4 |
| 2017 | 65.6 | 34.6 |
| 2016 | 71.5 | 41.4 |
| 2015 | 66.7 | 35 |
| 2014 | 48.4 | 40.6 |
| 2013 | 53.1 | 37.8 |
| 2012 | 72.9 | 42.3 |
| 2011 | 66.1 | 35.6 |
| 2010 | 78.5 | 45.6 |
| 2009 | 69.4 | 33 |
| 2008 | 69.8 | 38.8 |
| 2007 | 62.3 | 38.2 |
| 2006 | 70.8 | 40.8 |
| 2005 | 64 | 28.9 |
| 2004 | 67 | 36.2 |
| 2003 | 65 | 35.2 |
| 2002 | 56.8 | 33.4 |
| 2001 | 71.7 | 49 |
| 2000 | 69.8 | 38.2 |
| 1999 | 50.1 | 21 |
| 1998 | 65.5 | 38.8 |
| 1997 | 60.9 | 35.8 |
| 1996 | 71.2 | 41.6 |
| 1995 | 60.6 | 35.3 |
| 1994 | 77.2 | 44.2 |
| 1993 | 67.2 | 39.8 |
| 1992 | 70.1 | 33 |
| 1991 | 63.7 | 42.1 |
| 1990 | 62.5 | 36.2 |
| 1989 | 72.6 | 41.8 |
| 1988 | 53.7 | 33.1 |
| 1987 | 60.6 | 30.7 |
| 1986 | 43.2 | 32.8 |
| 1985 | 31.6 | 15.4 |
| 1984 | 47.7 | 20.1 |
| 1983 | 43.1 | 34.3 |
| 1982 | 39.1 | 33.7 |
| 1981 | 53.7 | 41.5 |
| 1980 | 67.7 | 37.7 |
| 1979 | 71.2 | 36.2 |
| 1978 | 58.3 | 38.4 |
| 1977 | 53.7 | 42 |
| 1976 | 68.1 | 39.8 |
| 1975 | 62.5 | 35.9 |
| 1974 | 60.2 | 30.8 |
| 1973 | 70.7 | 35.9 |
| 1972 | 48.6 | 24.2 |
| 1971 | 44.6 | 30.6 |
| 1970 | 71.6 | 35.6 |
| 1969 | 65.4 | 39.1 |
| 1968 | 63.5 | 35.8 |
| 1967 | 79 | 48 |
| 1966 | 63.1 | 44.8 |
| 1965 | 42.9 | 29.2 |
| 1964 | 61.1 | 36 |
| 1963 | 76.3 | 41.6 |
| 1962 | 59.7 | 37.8 |
| 1961 | 47.9 | 30.7 |
| 1960 | 63.4 | 29.3 |
| 1959 | 39.6 | 23.7 |
| 1958 | 58.7 | 36.4 |
| 1957 | 72.1 | 39.3 |
| 1956 | 53.3 | 35.4 |
| 1955 | 48 | 32.8 |
| 1954 | 37.3 | 31.8 |
| 1953 | 62.1 | 30.9 |
| 1952 | 70.1 | 38 |
| 1951 | 63 | 36.1 |
The month
September 2026 so far averaged 53.4°F in Jefferson County, MT, the warmest 1 to 29 September in the county average since 2025, 27th warmest of 76 (county average from NOAA gridded data, 1951 to 2026).
The month in words
- August 2026 averaged 62.7°F in Jefferson County, MT, the warmest August in the county average since 2023, tied 29th warmest of 132 (with 1949) (county average from NOAA's monthly county data, 1895 to 2026).
- Tuesday 29 September 2026: a high of 62.2°F averaged over Jefferson County, MT, the coldest 29 September day in the county average since 2023, 34th coldest of 76 (county average from NOAA gridded data, 1951 to 2026).
- Tuesday 29 September 2026: a low of 36.2°F averaged over Jefferson County, MT, the warmest 29 September night in the county average since 2025, tied 33rd warmest of 76 (with 2004, 1990 and 1979) (county average from NOAA gridded data, 1951 to 2026).
- Days of the month without a value
- 0
Nearby
Helena, MT 33.3 mi, the nearest city with its own station