August weather forecast
Isle Royale National Park, MI

In August, the weather begins to mellow down from the peak in July. However, the summer heat still predominates, although slightly less intense than July. Rainfall shows a marginal increase, retaining moisture within the environment. Daylight hours start to decline, hinting at the upcoming autumn. Despite the decrease in sunlight, temperatures still oscillate between 52°F (11.1°C) and 72°F (22.2°C), maintaining the warmth.

Temperature

The transition into August marks the average high-temperature at an agreeable 71.6°F (22°C), differing minimally from July's 75.2°F (24°C). Throughout August, the nighttime temperature averages to a fresh 51.8°F (11°C).

Rainfall

In August, in Isle Royale National Park, the rain falls for 12 days. Throughout August, 3.31" (84mm) of precipitation is accumulated. In Isle Royale National Park, Michigan, during the entire year, the rain falls for 125 days and collects up to 30.55" (776mm) of precipitation.

Ocean temperature

August is the month with the warmest seawater in Isle Royale National Park, with an average ocean temperature of 55.4°F (13°C).
Note: At temperatures below 50°F (10°C), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 55.4°F (13°C) is not comfortable.

Daylight

In August, the average length of the day is 14h and 14min.
On the first day of the month, sunrise is at 6:32 am and sunset at 9:30 pm. On the last day of August, in Isle Royale National Park, sunrise is at 7:13 am and sunset at 8:38 pm EDT.

Sunshine

The average sunshine in August in Isle Royale National Park is 8h.

UV index

The average daily maximum UV index in August is 6. A UV Index estimate of 6 to 7 represents a high health risk from exposure to the Sun's UV radiation for the average person.
Note: In August, the maximum UV index of 6 translates into these guidelines:
Deter overexposure. Protecting against the sun's effects is essential. Limit direct sun exposure and seek shade between 10 a.m. and 4 p.m., the time of the most intense UV radiation, noting that shade structures may not provide total sun protection. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.