Weather on August 15 at Isle Royale
Isle Royale National Park
Based on 50 years of data from Houghton, MI
Planning Your Visit
August 15th in Isle Royale National Park (via Houghton, MI) typically brings pleasant summer weather, with average highs around 76°F and lows near 55°F. Over 50 years of records, the warmest August 15th was in 2003 (78°F average), while the coldest was 1979 (53°F) — a 25°F range across recorded history. Rain or other precipitation has occurred on about 32% of August 15th dates historically, with the wettest August 15th recording 2.44" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for August 15th 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 | 84°F | 68°F | 0.51" | -- |
| 2024 | 78°F | 60°F | 1.6" | -- |
| 2023 | 79°F | 50°F | 0.05" | -- |
| 2022 | 73°F | 55°F | 0" | -- |
| 2021 | 91°F | 55°F | 0" | -- |
| 2020 | 75°F | 63°F | 0" | -- |
| 2019 | 77°F | 46°F | 0" | -- |
| 2018 | 72°F | 57°F | 0" | -- |
| 2017 | 70°F | 49°F | 0" | -- |
| 2016 | 80°F | 53°F | 0" | -- |
| 2015 | 88°F | 59°F | 0" | -- |
| 2014 | 77°F | 48°F | 1.04" | -- |
| 2013 | 74°F | 50°F | 0" | -- |
| 2012 | 76°F | 50°F | 0" | -- |
| 2011 | 80°F | 53°F | 0" | -- |
| 2010 | 74°F | 59°F | 0.23" | -- |
| 2009 | 90°F | 64°F | 0" | -- |
| 2008 | 76°F | 46°F | 0" | -- |
| 2007 | 71°F | 45°F | 0.2" | -- |
| 2006 | 71°F | 49°F | 0" | -- |
| 2005 | 79°F | 46°F | 0" | -- |
| 2004 | 74°F | 50°F | 0" | -- |
| 2003 | 88°F | 69°F | 0" | 0" |
| 2002 | 79°F | 64°F | 0.61" | 0" |
| 2001 | 80°F | 64°F | 0.18" | 0" |
| 2000 | 78°F | 66°F | 0.1" | 0" |
| 1999 | 77°F | 55°F | 0.53" | 0" |
| 1998 | 71°F | 57°F | 0" | 0" |
| 1997 | 73°F | 57°F | 2.44" | 0" |
| 1996 | 67°F | 52°F | 0.94" | 0" |
| 1995 | 86°F | 64°F | 0" | 0" |
| 1994 | 76°F | 50°F | 0" | 0" |
| 1993 | 76°F | 59°F | 0.38" | 0" |
| 1992 | 73°F | 47°F | 0" | 0" |
| 1991 | 85°F | 68°F | 0" | 0" |
| 1990 | 76°F | 54°F | 0" | 0" |
| 1989 | 66°F | 54°F | 0" | 0" |
| 1988 | 83°F | 59°F | 0" | 0" |
| 1983 | 80°F | 62°F | 0" | 0" |
| 1981 | 68°F | 50°F | 0" | 0" |
| 1980 | 64°F | 52°F | 0" | 0" |
| 1979 | 61°F | 45°F | 0" | 0" |
| 1978 | 80°F | 66°F | 1.4" | 0" |
| 1977 | 67°F | 51°F | 0.58" | 0" |
| 1976 | 65°F | 46°F | 0" | 0" |
| 1975 | 77°F | 59°F | 0" | 0" |
| 1974 | 83°F | 55°F | 0.18" | 0" |
| 1973 | 74°F | 55°F | 0" | 0" |
| 1972 | 75°F | 52°F | 0" | 0" |
| 1971 | 74°F | 39°F | 0" | 0" |