September weather forecastGrand Marais, MN
September weather for Grand Marais, Minnesota: In Grand Marais, Minnesota, during September, the rain falls for 12.5 days and regularly aggregates up to 1.97" (50mm) of precipitation. In Grand Marais, Minnesota, snow does not fall in June through September.

September
Weather in September
September in Grand Marais welcomes the onset of autumn, with the temperatures starting to decline from August, yet it's not as cool as October. The city witnesses the leaves changing color, adding a new visual charm. An interesting feature is the average high temperature falling from 68°F (20°C) in August to 60.8°F (16°C) in September. As the month progresses, the cool air begins to hint at the change of season. Still, the pleasant weather provides opportunities for outdoor exploration.Temperature
Transition into September in Grand Marais subtly marks a drop in the average high-temperature, moderately moving from an agreeable 68°F (20°C) in August to a comfortable 60.8°F (16°C). In the month of September, the temperature in Grand Marais generally rests at an average low of 50.7°F (10.4°C).Humidity
The average relative humidity in September in Grand Marais is 80%.Rainfall
In September, the rain falls for 12.5 days. Throughout September, 1.97" (50mm) of precipitation is accumulated. Throughout the year, there are 134.4 rainfall days, and 21.42" (544mm) of precipitation is accumulated.Snowfall
In Grand Marais, Minnesota, snow does not fall in June through September.Daylight
In September, the average length of the day in Grand Marais is 12h and 33min.On the first day of the month, sunrise is at 6:20 am and sunset at 7:41 pm. On the last day of September, sunrise is at 7:00 am and sunset at 6:42 pm CDT.
Sunshine
In September, the average sunshine is 9h.UV index
The average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: A maximum high daily UV index of 3 during September translates into the following directions:
Ensure safety - Imperative it is to shield skin and eyes from damage. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Grand Marais, MN
- Average high temperature in September: 60.8°F
The warmest month (with the highest average high temperature) is August (68°F).
The month with the lowest average high temperature is January (18.3°F).
- Average low temperature in September: 50.7°F
The month with the highest average low temperature is August (56.5°F).
The coldest month (with the lowest average low temperature) is January (8.1°F).
Average pressure in September
Grand Marais, MN
- Average pressure in September: 29.98"Hg
The months with the highest atmospheric pressure are February and March (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Grand Marais, MN
- Average wind speed in September: 8.9mph
The windiest month (with the highest average wind speed) is January (11.9mph).
The calmest month (with the lowest average wind speed) is July (7.2mph).
Average humidity in September
Grand Marais, MN
- Average humidity in September: 80%
The month with the highest relative humidity is January (88%).
The month with the lowest relative humidity is May (74%).
Average rainfall in September
Grand Marais, MN
- Average rainfall in September: 1.97"
The wettest month (with the highest rainfall) is July (2.36").
The driest month (with the least rainfall) is February (1.02").
Average rainfall days in September
Grand Marais, MN
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is July (15.4 days).
The month with the least rainy days is February (4.3 days).
Average snowfall in September
Grand Marais, MN
- Average snowfall in September: 0"
The month with the highest snowfall is December (6.5").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Grand Marais, MN
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (18.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Grand Marais, MN
- Average daylight in September: 12h and 36min
The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in September: 9h and 0min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 3h and 18min).
Average sunshine days in September
Grand Marais, MN
- Average sunshine days in September: 15.2 days
The month with the most sunshine days is September (15.2 days).
The month with the least sunshine days is January (10.3 days).
Average UV index in September
Grand Marais, MN
- Average UV index in September: 3
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in September
Grand Marais, MN
- Average cloud cover in September: 36
The month with the most cloud cover is January (Cloud cover 68).
The months with the least cloud cover are July and August (Cloud cover 31).
Average visibility in September
Grand Marais, MN
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).





