Weather on May 20 at Isle Royale
Isle Royale National Park
Based on 51 years of data from Houghton, MI
Planning Your Visit
May 20th in Isle Royale National Park (via Houghton, MI) typically brings mild spring weather, with average highs around 65°F and lows near 43°F. Over 51 years of records, the warmest May 20th was in 1992 (71°F average), while the coldest was 2007 (36°F) — a 35°F range across recorded history. Rain or other precipitation has occurred on about 35% of May 20th dates historically, with the wettest May 20th recording 2.46" of rain. The last decade has been 1.2°F cooler on this date compared to 20-30 years ago.
The last decade has been 1.2°F cooler on this date compared to 20-30 years ago.
Planning for May 20th in Isle Royale? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.
Year by Year History
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2026 | 51°F | 29°F | 0" | -- |
| 2025 | 52°F | 35°F | 0" | -- |
| 2024 | 67°F | 52°F | 0" | -- |
| 2023 | 70°F | 39°F | 0" | -- |
| 2022 | 66°F | 45°F | 0.23" | -- |
| 2021 | 74°F | 64°F | 0.15" | -- |
| 2020 | 70°F | 45°F | 0" | -- |
| 2019 | 56°F | 40°F | 0" | -- |
| 2018 | 67°F | 30°F | 0" | -- |
| 2017 | 49°F | 35°F | 0.13" | -- |
| 2016 | 73°F | 42°F | 0" | -- |
| 2015 | 60°F | 31°F | 0" | -- |
| 2014 | 55°F | 45°F | 1.57" | -- |
| 2013 | 49°F | 44°F | 1.35" | -- |
| 2012 | 79°F | 44°F | 2.46" | -- |
| 2011 | 70°F | 48°F | 0" | -- |
| 2010 | 69°F | 49°F | 0" | -- |
| 2009 | 90°F | 35°F | 0" | -- |
| 2008 | 47°F | 38°F | 0.13" | -- |
| 2007 | 42°F | 31°F | 0.03" | -- |
| 2006 | 59°F | 37°F | 0.36" | -- |
| 2005 | 70°F | 41°F | 0" | -- |
| 2004 | 61°F | 40°F | 0" | -- |
| 2003 | 69°F | 39°F | 0.94" | 0" |
| 2002 | 49°F | 27°F | 0" | 0" |
| 2001 | 81°F | 47°F | 0" | 0" |
| 2000 | 69°F | 32°F | 0" | 0" |
| 1999 | 70°F | 41°F | 0" | 0" |
| 1998 | 80°F | 50°F | 0" | 0" |
| 1997 | 51°F | 37°F | 0.08" | 0" |
| 1996 | 65°F | 52°F | 0" | 0" |
| 1995 | 62°F | 46°F | 0" | 0" |
| 1994 | 88°F | 46°F | 0" | 0" |
| 1993 | 58°F | 42°F | 0" | 0" |
| 1992 | 85°F | 57°F | 0" | 0" |
| 1991 | 73°F | 41°F | 0" | 0" |
| 1990 | 56°F | 40°F | 0" | 0" |
| 1989 | 66°F | 47°F | 0.46" | 0" |
| 1988 | 78°F | 49°F | 0" | 0" |
| 1982 | 51°F | 35°F | 0.05" | 0" |
| 1981 | 78°F | 50°F | 0" | 0" |
| 1980 | 82°F | 47°F | 0" | 0" |
| 1979 | 46°F | 39°F | 0.66" | 0" |
| 1978 | 57°F | 35°F | 0.2" | 0" |
| 1977 | 82°F | 55°F | 0.81" | 0" |
| 1976 | 66°F | 46°F | 0" | 0" |
| 1975 | 75°F | 52°F | 0" | 0" |
| 1974 | 72°F | 43°F | 0" | 0" |
| 1973 | 59°F | 45°F | 0" | 0" |
| 1972 | 77°F | 56°F | 0.03" | 0" |
| 1971 | 48°F | 34°F | 0.2" | 0" |