Yosemite National Park is definitely worth a visit
Vast forests, blue lakes, towering sequoias, and majestic waterfalls hint at the beauty of Yosemite National Park—a true natural masterpiece.
St. Charles Weather in September
In St. Charles, September brings high daytime temperatures around 27°C (81°F), with nights cooling to 15°C (59°F). Expect quite a bit of rainfall this month.
Rainfall in St. Charles in September
Historically, the month has about 8 days of rain, averaging 96 mm (3.8 in) in total. Individual showers can be quite heavy this month. A proper umbrella or rain jacket is worth having.
Temperature in St. Charles in September
If you're visiting St. Charles in September, expect excellent temperatures with highs of 27°C (81°F) and overnight lows of 15°C (59°F). Conditions stay fairly consistent through the month, making it easier to plan what to wear. At 15°C (59°F) overnight, it can feel quite a bit cooler after dark. Worth packing something warmer for evenings, but the cooler temperatures are ideal for sleeping.
Sunshine in St. Charles in September
There are approximately 235 hours of sunshine this month, resulting in mostly clear days.So this is a great month to visit if you prefer dry days with pleasant temperatures.
St. Charles Temperature in September
Min Temperature
15°C (59°F)
Max Temperature
27°C (81°F)
Chance of Rain
28%
Precipitation
96 mm (3.8 in)
Rainy days
8 days
Humidity
71% *
Sunshine
235 hours *
Percentage Sunshine
63% *
* Data from: St. Louis, the United States of America (30 KM, 18 Miles).
St. Charles Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in St. Charles - and find the best time to visit.
Best Places in the United States of America in September
Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in September →
perfect weather
pleasant
tolerable
unpleasant
poor
Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).
What to Wear in St. Charles in September
Warm temperatures in September make for comfortable sightseeing weather. Pack breathable fabrics like cotton shirts, knee-length shorts or skirts, and comfortable walking shoes. A thin long sleeve for indoor spaces is handy. Prepare for significant rainfall with proper waterproof clothing and shoes. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.
What To Do in St. Charles in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
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Swimming9/10 -
Cycling7/10 -
Walking7/10 -
Camping8/10 -
Outdoor sports7/10
St. Charles 3-Day Forecast
More climate data for St. Charles
Temperature Rainfall Sunshine Humidity
See the full St. Charles climate overview or explore weather in the United States of America.
Popular in September
Where to go in September - average daytime high across popular destinations.
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