September weather forecastWinthrop Harbor, IL
September
Weather in September
The first month of the autumn, September, is still a pleasant month in Winthrop Harbor, Illinois, with an average temperature fluctuating between 58.5°F (14.7°C) and 70.9°F (21.6°C).Temperature
In September, the average high-temperature marginally drops from a warm 77°F (25°C) in August to a pleasant 70.9°F (21.6°C). Winthrop Harbor's temperature tends to fall to an average low of 58.5°F (14.7°C) during the nights of September.Humidity
In September, the average relative humidity in Winthrop Harbor is 77%.Rainfall
In Winthrop Harbor, in September, it is raining for 12.7 days, with typically 1.73" (44mm) of accumulated precipitation. In Winthrop Harbor, during the entire year, the rain falls for 142.5 days and collects up to 21.5" (546mm) of precipitation.Snowfall
May through September are months without snowfall.Daylight
The average length of the day in September in Winthrop Harbor is 12h and 28min.On the first day of the month, sunrise is at 6:17 am and sunset at 7:24 pm. On the last day of September, sunrise is at 6:48 am and sunset at 6:33 pm CDT.
Sunshine
The average sunshine in September in Winthrop Harbor, Illinois, is 9.2h.UV index
In September, the average daily maximum UV index in Winthrop Harbor, Illinois, is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the average person.Note: The daily high UV index of 4 in September translates into this advice:
Guard yourself - Avoiding sunburn is suggested. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. In bright sunlight, prioritize sunglasses that grant protection from UVA and UVB radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Winthrop Harbor, IL
- Average high temperature in September: 70.9°F
The warmest month (with the highest average high temperature) is July (77.5°F).
The month with the lowest average high temperature is January (27.9°F).
- Average low temperature in September: 58.5°F
The month with the highest average low temperature is July (65.3°F).
The coldest month (with the lowest average low temperature) is January (18.3°F).
Average pressure in September
Winthrop Harbor, IL
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Winthrop Harbor, IL
- Average wind speed in September: 8.8mph
The windiest month (with the highest average wind speed) is January (11.9mph).
The calmest month (with the lowest average wind speed) is August (7.3mph).
Average humidity in September
Winthrop Harbor, IL
- Average humidity in September: 77%
The month with the highest relative humidity is January (83%).
The months with the lowest relative humidity are October and November (75%).
Average rainfall in September
Winthrop Harbor, IL
- Average rainfall in September: 1.73"
The wettest months (with the highest rainfall) are June and August (2.68").
The driest month (with the least rainfall) is December (0.91").
Average rainfall days in September
Winthrop Harbor, IL
- Average rainfall days in September: 12.7 days
The month with the highest number of rainy days is July (17 days).
The month with the least rainy days is February (5.2 days).
Average snowfall in September
Winthrop Harbor, IL
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.6").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Winthrop Harbor, IL
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (12.4 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Winthrop Harbor, IL
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 9h and 12min
The months with the most sunshine are July and August (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in September
Winthrop Harbor, IL
- Average sunshine days in September: 13.9 days
The month with the most sunshine days is November (16.5 days).
The month with the least sunshine days is July (10.8 days).
Average UV index in September
Winthrop Harbor, IL
- Average UV index in September: 4
The months with the highest UV index are July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Winthrop Harbor, IL
- Average cloud cover in September: 29
The month with the most cloud cover is January (Cloud cover 61).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Winthrop Harbor, IL
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
