May weather forecast
Isle Royale National Park, MI

May ushers in the true essence of spring with its mild and comfortable climate. It offers a respite from the long, dreary winter. Following April, May continues the trend of increased daylight hours. Rainfall is expected to be slightly higher than the previous month, making the location greener. The temperature exhibits a considerable rise, averaging from 37°F (2.8°C) to 59°F (15°C), engendering the warmth of spring.

Temperature

Entering May, Isle Royale National Park sees a temperature rise, with the average high-temperature advancing from April's chilly 46.4°F (8°C) to a refreshing 59°F (15°C). Despite considerable daily temperature swings, a steady low-temperature average of 37.4°F (3°C) is noted in Isle Royale National Park throughout May.

Rainfall

In Isle Royale National Park, in May, during 10 rainfall days, 2.68" (68mm) of precipitation is typically accumulated. In Isle Royale National Park, during the entire year, the rain falls for 125 days and collects up to 30.55" (776mm) of precipitation.

Ocean temperature

In May, the average ocean temperature is 37.4°F (3°C).
Note: For swimming, this is considered life-threatening and very dangerous. The water feels painfully cold, and hyperventilation quickly occurs. A specialized swimsuit is mandatory to reduce thermal damage.

Daylight

In Isle Royale National Park, the average length of the day in May is 15h and 12min.
On the first day of May, sunrise is at 6:35 am and sunset at 9:09 pm. On the last day of the month, sunrise is at 6:00 am and sunset at 9:46 pm EDT.

Sunshine

In Isle Royale National Park, the average sunshine in May is 8h.

UV index

The average daily maximum UV index in May in Isle Royale National Park is 6. A UV Index reading of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV radiation for the ordinary person.
Note: The maximum UV index of 6 during May leads to these instructions:
Take precautions against overexposure. Fair-skinned people may get burned in less than 20 minutes. Seek shade and limit direct sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Keep in mind that shade structures like parasols or canopies do not offer complete sun protection. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes.