# Heating degree days in Montana

Heating degree days in Montana was 8,014 degree days (base 65°F) in 2025. Source: NOAA National Centers for Environmental Information.

- Indicator id: `heating_degree_days_annual`
- Place id: `us-state-30`
- Unit: degree days (base 65°F)
- Definition: Sum over January to December of the degrees by which the daily mean temperature falls below 65°F, a measure of heating demand. NOAA estimates monthly values from nClimDiv temperatures and weights areas by population (2010 Census).
- Note: NOAA publishes these for operational monitoring; they can differ from official degree day publications.
- Source: NOAA National Centers for Environmental Information, NOAA Climate at a Glance, January to December heating degree days (base 65°F), contiguous US and statewide (https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/statewide/time-series/24/hdd/12/12/1895-2025/data.json)
- Publisher page: https://invokely.ai/en/publishers/noaa-ncei
- Retrieved: 2026-10-12
- License: Public domain (US government work); NCEI asks users to cite the nClimDiv dataset
- Citation: NOAA National Centers for Environmental Information, Climate at a Glance. NOAA Climate at a Glance, January to December heating degree days (base 65°F), contiguous US and statewide. From the NOAA Monthly U.S. Climate Divisional Database (nClimDiv), doi:10.7289/V5M32STR. https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/statewide/time-series/24/hdd/12/12/1895-2025/data.json. Retrieved 2026-10-12.
- Web page: https://invokely.ai/en/heating-degree-days/montana
- API: https://invokely.ai/api/v1/series?indicator=heating_degree_days_annual&place=us-state-30

| Period | degree days (base 65°F) |
|---|---:|
| 2025 | 8,014 |
| 2024 | 8,016 |
| 2023 | 8,204 |
| 2022 | 8,821 |
| 2021 | 8,203 |
| 2020 | 8,300 |
| 2019 | 9,290 |
| 2018 | 8,739 |
| 2017 | 8,448 |
| 2016 | 7,890 |
| 2015 | 7,708 |
| 2014 | 8,613 |
| 2013 | 8,569 |
| 2012 | 8,008 |
| 2011 | 8,868 |
| 2010 | 8,712 |
| 2009 | 8,948 |
| 2008 | 8,959 |
| 2007 | 8,199 |
| 2006 | 8,106 |
| 2005 | 8,455 |
| 2004 | 8,312 |
| 2003 | 8,327 |
| 2002 | 8,989 |
| 2001 | 8,270 |
| 2000 | 8,651 |
| 1999 | 8,112 |
| 1998 | 8,276 |
| 1997 | 8,774 |
| 1996 | 9,544 |
| 1995 | 8,784 |
| 1994 | 8,421 |
| 1993 | 9,448 |
| 1992 | 8,171 |
| 1991 | 8,607 |
| 1990 | 8,601 |
| 1989 | 9,119 |
| 1988 | 8,196 |
| 1987 | 8,018 |
| 1986 | 8,420 |
| 1985 | 9,814 |
| 1984 | 9,027 |
| 1983 | 8,910 |
| 1982 | 9,640 |
| 1981 | 8,202 |
| 1980 | 8,741 |
| 1979 | 9,291 |
| 1978 | 9,630 |
| 1977 | 8,910 |
| 1976 | 8,614 |
| 1975 | 9,703 |
| 1974 | 8,640 |
| 1973 | 8,849 |
| 1972 | 9,400 |
| 1971 | 9,299 |
| 1970 | 9,265 |
| 1969 | 9,372 |
| 1968 | 9,173 |
| 1967 | 8,834 |
| 1966 | 8,872 |
| 1965 | 9,286 |
| 1964 | 9,304 |
| 1963 | 8,612 |
| 1962 | 8,903 |
| 1961 | 8,624 |
| 1960 | 9,098 |
| 1959 | 9,291 |
| 1958 | 8,438 |
| 1957 | 9,243 |
| 1956 | 9,046 |
| 1955 | 9,919 |
| 1954 | 8,936 |
| 1953 | 8,150 |
| 1952 | 9,012 |
| 1951 | 10,105 |
| 1950 | 9,774 |
| 1949 | 9,490 |
| 1948 | 9,379 |
| 1947 | 8,956 |
| 1946 | 8,781 |
| 1945 | 9,095 |
| 1944 | 8,976 |
| 1943 | 9,219 |
| 1942 | 9,180 |
| 1941 | 8,488 |
| 1940 | 8,508 |
| 1939 | 8,265 |
| 1938 | 8,705 |
| 1937 | 9,479 |
| 1936 | 9,206 |
| 1935 | 9,209 |
| 1934 | 7,657 |
| 1933 | 8,788 |
| 1932 | 9,348 |
| 1931 | 8,377 |
| 1930 | 9,101 |
| 1929 | 9,826 |
| 1928 | 9,000 |
| 1927 | 9,688 |
| 1926 | 8,536 |
| 1925 | 8,523 |
| 1924 | 9,491 |
| 1923 | 9,035 |
| 1922 | 9,706 |
| 1921 | 8,727 |
| 1920 | 9,328 |
| 1919 | 9,318 |
| 1918 | 8,941 |
| 1917 | 9,616 |
| 1916 | 10,362 |
| 1915 | 8,887 |
| 1914 | 8,877 |
| 1913 | 9,584 |
| 1912 | 9,512 |
| 1911 | 9,725 |
| 1910 | 8,527 |
| 1909 | 9,653 |
| 1908 | 8,950 |
| 1907 | 9,483 |
| 1906 | 8,827 |
| 1905 | 9,133 |
| 1904 | 8,741 |
| 1903 | 9,347 |
| 1902 | 9,301 |
| 1901 | 8,822 |
| 1900 | 8,438 |
| 1899 | 9,789 |
| 1898 | 9,383 |
| 1897 | 9,277 |
| 1896 | 9,319 |
| 1895 | 9,583 |