easeweather.com
Saint Louis County (Eureka)
Akron (OH)Albuquerque (NM)Alexandria (VA)Anaheim (CA)Anchorage (AK)Arlington (VA)Atlanta (GA)Atlantic City (NJ)Austin (TX)Baltimore (MD)Baton Rouge (LA)Birmingham (AL)Boston (MA)Brooklyn (NY)Buffalo (NY)Cape Coral (FL)Charlotte (NC)Chattanooga (TN)Chicago (IL)Cincinnati (OH)Cleveland (OH)Colorado Springs (CO)Columbus (OH)Corpus Christi (TX)Dallas (TX)Dayton (OH)Denver (CO)Des Moines (IA)Detroit (MI)El Paso (TX)Eureka (MO)Fairbanks (AK)Fayetteville (NC)Fort Lauderdale (FL)Fort Wayne (IN)Fort Worth (TX)Gatlinburg (TN)Grand Rapids (MI)Harrisburg (PA)Honolulu (HI)Houston (TX)Huntsville (AL)Indianapolis (IN)Jackson (MS)Jacksonville (FL)Juneau (AK)Kansas City (MO)Ketchikan (AK)Key West (FL)Knoxville (TN)Las Vegas (NV)Lexington (KY)Lincoln (NE)Little Rock (AR)Los Angeles (CA)Louisville (KY)Madison (WI)Manhattan (NY)Memphis (TN)Miami (FL)Milwaukee (WI)Minneapolis (MN)Mobile (AL)Montgomery (AL)Nashville (TN)New Orleans (LA)New York City (NY)Newark (NJ)Oklahoma City (OK)Omaha (NE)Orlando (FL)Philadelphia (PA)Phoenix (AZ)Pittsburgh (PA)Portland (OR)Richmond (VA)Riverside (CA)Sacramento (CA)Salt Lake City (UT)San Antonio (TX)San Diego (CA)San Francisco (CA)San Jose (CA)Savannah (GA)Seattle (WA)Sitka (AK)Skagway (AK)Springfield (MO)St. Louis (MO)St. Petersburg (FL)Tallahassee (FL)Tampa (FL)Toledo (OH)Traverse City (MI)Tulsa (OK)Tyler (TX)Vancouver (WA)Virginia Beach (VA)WashingtonWichita (KS)Winston-Salem (NC) More Locations
United States weather

Weather in Saint Louis County, Missouri for September 2025

Your guide to Saint Louis County weather in September - trends and predictions

    Official Weather Alert ⚠️

  • Meteorological - Air Quality Alert - See hour by hour.

    • Temperatures

  • Until now, September 2025 in Saint Louis County is slightly cooler than the historical average by -0.8 °F.

  • The forecast for the coming days of September 2025 predicts a temperature of 32.4 °F , which is warmer than usual.

  • In general, the average temperature in Saint Louis County at the beginning of September is 26.6 °F. As the month progressed, temperatures tended to significantly warm up, reaching an average of 30.7 °F by the end of September.

    • Rain 🌧️

  • Saint Louis County experiences moderate rainfall in September, with an average of 6 rainy days and a total precipitation of 110.8 mm.

    • More

  • New! Chat with our AI weatherman - it’s amazing and free.

Average dry days
24
Dry days
Average rainy days
6
Rainy days
Average snowy days
0
Snow days
Average temperatures
27°/16°
Temperatures
Average wind speed
13 km/h
Avg max wind
Average humidity
64 %
Avg humidity

Saint Louis County Weather September

Move between months or click on a day
August
October
Sun.Mon.Tue.Wed.Thu.Fri.Sat.
1
Fog
29°
2
Sunny
29°
3
Overcast
26°
4
Sunny
27°
5
Partly cloudy
26°
6
Patchy rain possible
26°
7
Sunny
23°
8
Sunny
25°
9
Sunny
26°
10
Sunny
30°
11
Partly cloudy
33°
12
Sunny
31°
13
Patchy rain possible
30°
14
Mist
31°
15
Weather Alert Sunny
34°
16
Partly cloudy
32°
17
Partly cloudy
33°
18
Patchy rain possible
36°
19
Patchy rain possible
27°
20
Patchy rain possible
32°
21
Moderate rain
25°
22
Patchy rain possible
32°
23
Patchy rain possible
35°
24
Sunny
35°
25
Sunny
36°
26
Sunny
33°
27
Sunny
33°
28
Partly cloudy
30°
29
Overcast
22°
30
Mist
26°

Temperatures trend during September in Saint Louis County

See the weather trend as well as the moving average line

September weather in Saint Louis County day by day

Click on a date for more information
August October
Date Weather Temperatures Rain UV More
Sept. 1 Fog
Fog
 29° /18° 0 mm 7
Sept. 2 Sunny
Sunny
 29° /17° 0 mm 7
Sept. 3 Overcast
Overcast
 26° /15° 0 mm 6
Sept. 4 Sunny
Sunny
 27° /15° 7.2 mm 7
Sept. 5 Partly cloudy
Partly cloudy
 26° /15° 0 mm 7
Sept. 6 Patchy rain possible
Patchy rain possible
 26° /15° 14.1 mm 6
Sept. 7 Sunny
Sunny
 23° /11° 0 mm 6
Sept. 8 Sunny
Sunny
 25° /9° 0 mm 7
Sept. 9 Sunny
Sunny
 26° /11° 0 mm 6
Sept. 10 Sunny
Sunny
 30° /14° 0 mm 8
Sept. 11 Partly cloudy
Partly cloudy
 33° /18° 0 mm 8
Sept. 12 Sunny
Sunny
 31° /19° 0 mm 8
Sept. 13 Patchy rain possible
Patchy rain possible
 30° /20° 2.2 mm 7
Sept. 14 Mist
Mist
 31° /20° 0 mm 7
Sept. 15 Sunny
Sunny
 34° /24° 0 mm 1.6
Sept. 16 Partly cloudy
Partly cloudy
 32° /22° 0 mm 1.6
Sept. 17 Partly cloudy
Partly cloudy
 33° /21° 0 mm 1.5
Sept. 18 Patchy rain possible
Patchy rain possible
 36° /19° 0.2 mm 1.1
Sept. 19 Patchy rain possible
Patchy rain possible
 27° /19° 2.9 mm 0
Sept. 20 Patchy rain possible
Patchy rain possible
 32° /17° 0.2 mm 5
Sept. 21 Moderate rain
Moderate rain
 25° /18° 7.8 mm 5
Sept. 22 Patchy rain possible
Patchy rain possible
 32° /18° 0.6 mm 5
Sept. 23 Patchy rain possible
Patchy rain possible
 35° /20° 0.1 mm 6
Sept. 24 Sunny
Sunny
 35° /20° 0 mm 7
Sept. 25 Sunny
Sunny
 36° /21° 0 mm 7
Sept. 26 Sunny
Sunny
 33° /21° 0 mm 7
Sept. 27 Sunny
Sunny
 33° /19° 0 mm 6
Sept. 28 Partly cloudy
Partly cloudy
 30° /20° 0 mm 6
Sept. 29 Overcast
Overcast
 22° /19° 0 mm 5
Sept. 30 Mist
Mist
 26° /18° 0 mm 6
Next
Important Notice
Our weather forecast for Saint Louis County in September is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Saint Louis County forecast closer to your planned date for the most up-to-date weather information.
Change Month
‹
›

Saint Louis County in September - FAQ

What are the expected maximum and minimum temperatures in Saint Louis County during September?
During September, expect a variety of temperatures with highs around 27° and lows near 16°, suitable for diverse activities and preferences.
How much rainfall should be expected in Saint Louis County during September?
Significant rainfall exceeding 110.8 mm is expected in Saint Louis County during September, occurring over more than 6 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Saint Louis County during September?
The average wind speed in Saint Louis County during September is 13 km/h, suggesting breezy to windy conditions, depending on your activities.

September rainfall patterns in Saint Louis County

Explore the daily rainfall trends and prepare for Saint Louis Countys September weather 💧

UV exposure in Saint Louis County during September

Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
Top locations in Saint Louis County
Select a location for an accurate weather forecast
DuluthEureka
More Locations

Quick links

More Saint Louis County weather pages
You are here
Location coordinates Where is Saint Louis County?

Get accurate weather forecasts for Saint Louis County, located at latitude 38.503 and longitude -90.628. Stay updated with localized weather information tailored for Saint Louis County.

Found a mistake?
We appreciate your attention to details. Tell us here.