Weather on May 12 at Isle Royale

Isle Royale National Park

MIMidwest800 ft elevation
Avg High59°F
Avg Low39°F
Warmest202574°F
Coldest200532°F

Based on 50 years of data from Houghton, MI

Planning Your Visit

May 12th in Isle Royale National Park (via Houghton, MI) typically brings cool spring weather, with average highs around 59°F and lows near 39°F. Over 50 years of records, the warmest May 12th was in 2025 (74°F average), while the coldest was 2005 (32°F) — a 42°F range across recorded history. Precipitation has occurred on 38% of recorded May 12th dates, with snow falling 6% of the time (heaviest snowfall: 5.5"). The last decade has been 5.4°F warmer on this date compared to 20-30 years ago.

The last decade has been 5.4°F warmer on this date compared to 20-30 years ago.

Planning for May 12th in Isle Royale? Bring layers as temperatures can vary throughout the day. Consider bringing rain gear or an umbrella.

Year by Year History

YearHighLowPrecipSnow
202588°F61°F0"--
202477°F50°F0.08"--
202370°F50°F0"--
202263°F49°F0.89"--
202164°F30°F0"--
202049°F27°F0"--
201958°F36°F0"--
201862°F29°F0"--
201762°F33°F0"--
201662°F48°F0.74"--
201539°F34°F0.36"--
201445°F36°F2.03"--
201340°F30°F0.08"--
201264°F41°F0"--
201160°F50°F0.03"--
201054°F42°F0"--
200962°F30°F0"--
200849°F31°F0.08"--
200756°F37°F0"--
200646°F34°F1.5"--
200538°F27°F0"--
200486°F42°F0.15"--
200353°F38°F2.84"0"
200255°F40°F0.25"0"
200161°F34°F0"0"
200060°F48°F0"0"
199955°F51°F0"0"
199875°F42°F0"0"
199751°F31°F3.23"5.5"
199649°F30°F0"0"
199572°F46°F0"0"
199457°F36°F0"0"
199363°F36°F0"0"
199266°F45°F0.08"0"
199179°F58°F0"0"
199056°F40°F0"0"
198963°F38°F0"0"
198852°F35°F1.17"0"
198250°F42°F0.23"0"
198158°F34°F0"0"
198053°F38°F0"0"
197949°F37°F0"0"
197849°F39°F0"0"
197782°F56°F0"0"
197663°F33°F0"0"
197561°F37°F0"0"
197445°F36°F0.1"0"
197337°F32°F0.2"0.5"
197268°F41°F0"0"
197150°F29°F0.2"1.6"

May 12 at Nearby Parks

Holiday Weather at Isle Royale

Official NPS WebsiteVisit nps.gov/isro for park information, alerts, and reservations

Explore More at Isle Royale

See historical weather for other dates

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