Temperatures in September
It's cool to moderate in September in Isle Royale National Park with an average temperature of 18°C. Temperatures this month range from a low of 14°C to a high of 22°C. At night, you can expect temperatures between 6°C and 13°C.
Max and Min Temperatures per Day
This chart shows the daily maximum and minimum temperatures in degrees Celsius for Isle Royale National Park in September. The red line indicates the max temperatures, and the blue line shows the minimums.
Start of September
The month of September starts in Isle Royale National Park with mild temperatures, averaging around 20°C during the day and nights close to 11°C. You can expect regular precipitation, but there’s also a chance for some sunny days in the first days of the month.
Mid-September
By mid-September, the average daytime temperature drops to around 19°C, with nights close to 11°C. During this part of the month, you can expect regular precipitation, but there’ll also be some sunny days.
End of September
By the end of September, the average daytime temperature in Isle Royale National Park will be around 17°C, with nights close to 9°C. A shower might show up, but overall the weather will be dry and sunny.
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Precipitation in September
In September, there is an average of 130 mm of precipitation, spread over 10 days. The wind speed is around 5 Bft, mostly coming from the South.
The average precipitation chance is 34% per day this month.
Precipitation Chance
This chart shows the daily precipitation chance (in percentages) in September for Isle Royale National Park. 0% means it never rained on that day in the past 10 years, and 100% means it rained every day. All values in between represent the average chance of precipitation on that day.
Isle Royale National Park in September |
UK | ||
|---|---|---|---|
 Average Temperature |
18°C | 20°C | |
 High Temp |
22°C | 22°C | |
| Low Temp |
14°C | 17°C | |
 Total Precipitation |
130 mm | 44 mm | |
| Rainy Days |
10 days | 8 days | |
August
UV index
The UV index is a maximum of 7 this month. That's a moderate to high value on the intensity scale of 1 to 11. Unprotected skin can burn within 15-25 minutes.
Is September a good time to visit Isle Royale National Park?
After some sun? Then September isn’t the best time to be in Isle Royale National Park. The temperature is pleasant, but there’s too much chance of rain this month.
Temperature records for Isle Royale National Park in September
With 31°C, Isle Royale National Park hit the highest temperature in the last 10 years in September 2015. The lowest daytime temperature in this month was 6°C in 2018. The extreme night temperatures ranged from a low of -2°C to a high of 19°C.
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Daily Temperature in September in Isle Royale National Park
This chart shows the average daily temperatures, both day and night, for each day in September in Isle Royale National Park, measured in degrees Celsius. The red line represents the maximum temperatures, while the blue line shows the minimums. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, gives an overview of the average daily temperatures during this month.
Daily Precipitation in September in Isle Royale National Park
The chart below shows the average daily precipitation in September for Isle Royale National Park, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are shown at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that rain is more likely. But it’s still an average, so each day can be different. Based on historical weather data for September, you can expect around 10 days of rain in Isle Royale National Park.
Daily UV Index in September in Isle Royale National Park
This chart shows the average daily UV index in September in Isle Royale National Park, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in Isle Royale National Park Over the Years
This chart shows the average temperature in September in Isle Royale National Park, measured in degrees Celsius, over the past years.
Total Precipitation in September in Isle Royale National Park Over the Years
This chart shows the average precipitation in September in Isle Royale National Park, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail.
Daily climate in September for Isle Royale National Park
Click on a specific day in September for detailed info on the typical weather on that day in Isle Royale National Park. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Isle Royale National Park
Have you been to Isle Royale National Park in September?
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Average Weather in Isle Royale National Park by Month
Click on a month below to see detailed weather info for Isle Royale National Park. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
Or check out the climate of Isle Royale National Park for all months at once
