Weather on September 12 at Isle Royale
Isle Royale National Park
Based on 50 years of data from Houghton, MI
Planning Your Visit
September 12th in Isle Royale National Park (via Houghton, MI) typically brings mild fall weather, with average highs around 67°F and lows near 49°F. Over 50 years of records, the warmest September 12th was in 2005 (74°F average), while the coldest was 2014 (41°F) — a 33°F range across recorded history. Rain or other precipitation has occurred on about 42% of September 12th dates historically, with the wettest September 12th recording 1.98" of rain. The last decade has been 1.1°F cooler on this date compared to 20-30 years ago.
The last decade has been 1.1°F cooler on this date compared to 20-30 years ago.
Planning for September 12th in Isle Royale? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 71°F | 54°F | 0.43" | -- |
| 2024 | 78°F | 55°F | 0" | -- |
| 2023 | 56°F | 45°F | 0" | -- |
| 2022 | 73°F | 45°F | 0" | -- |
| 2021 | 66°F | 46°F | 0" | -- |
| 2020 | 62°F | 53°F | 1.98" | -- |
| 2019 | 56°F | 50°F | 1.57" | -- |
| 2018 | 81°F | 61°F | 0" | -- |
| 2017 | 79°F | 49°F | 0" | -- |
| 2016 | 80°F | 57°F | 0.13" | -- |
| 2015 | 62°F | 36°F | 0" | -- |
| 2014 | 50°F | 31°F | 0" | -- |
| 2013 | 59°F | 45°F | 0.1" | -- |
| 2012 | 75°F | 54°F | 0" | -- |
| 2011 | 86°F | 50°F | 1.91" | -- |
| 2010 | 64°F | 54°F | 0" | -- |
| 2009 | 78°F | 56°F | 0" | -- |
| 2008 | 69°F | 48°F | 0" | -- |
| 2007 | 51°F | 40°F | 0.05" | -- |
| 2006 | 61°F | 43°F | 0" | -- |
| 2005 | 85°F | 64°F | 1.04" | -- |
| 2004 | 56°F | 49°F | 0" | -- |
| 2003 | 76°F | 64°F | 0.48" | -- |
| 2002 | 81°F | 59°F | 0" | 0" |
| 2001 | 66°F | 55°F | 0.03" | 0" |
| 2000 | 72°F | 47°F | 0.64" | 0" |
| 1999 | 63°F | 50°F | 1.02" | 0" |
| 1998 | 85°F | 53°F | 0" | 0" |
| 1997 | 72°F | 41°F | 0" | 0" |
| 1996 | 60°F | 46°F | 1.3" | 0" |
| 1995 | 78°F | 49°F | 0" | 0" |
| 1994 | 80°F | 62°F | 0" | 0" |
| 1993 | 72°F | 52°F | 0" | 0" |
| 1992 | 77°F | 53°F | 0" | 0" |
| 1991 | 62°F | 55°F | 0.03" | 0" |
| 1990 | 65°F | 50°F | 1.09" | 0" |
| 1989 | 55°F | 43°F | 0.08" | 0" |
| 1988 | 74°F | 51°F | 0.23" | 0" |
| 1983 | 56°F | 43°F | 0" | 0" |
| 1981 | 74°F | 51°F | 0" | 0" |
| 1980 | 57°F | 47°F | 0.64" | 0" |
| 1979 | 56°F | 52°F | 0.89" | 0" |
| 1978 | 50°F | 47°F | 0.03" | 0" |
| 1977 | 64°F | 44°F | 0" | 0" |
| 1976 | 87°F | 56°F | 0" | 0" |
| 1975 | 47°F | 39°F | 0" | 0" |
| 1974 | 53°F | 45°F | 1.07" | 0" |
| 1973 | 56°F | 44°F | 0" | 0" |
| 1972 | 68°F | 43°F | 0" | 0" |
| 1971 | 66°F | 40°F | 0" | 0" |