Linn County (Cedar Rapids)
September
Weather in Linn County, Iowa for September 2026
Your guide to Linn County weather in September - trends and predictions
Flood Watch - See hour by hour.
So far, September 2026 in Linn County is slightly warmer than the historical average by 0.7 °F.
The forecast for the next days in Linn County predicts temperatures to be around 18 °F, close to the historical average.
In general, the average temperature in Linn County at the beginning of September is 27.3 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 18.3 °F by the end of September.
With an average of 4 rainy days, Linn County experiences minimal rainfall in September.
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Official Weather Alert ⚠️
Temperatures
Rain 🌧️
More
26
Dry days
4
Rainy days
0
Snow days
26°/14°
Temperatures
16 km/h
Avg max wind
75 %
Avg humidity
Linn County Weather September
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Temperatures trend during September in Linn County
See the weather trend as well as the moving average line
September weather in Linn County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Overcast | 30° /18° | 0 mm | 6 | |
| Sept. 2 |  Cloudy | 30° /18° | 0 mm | 7 | |
| Sept. 3 |  Moderate or heavy rain shower | 28° /17° | 12.7 mm | 6 | |
| Sept. 4 |  Mist | 28° /14° | 0 mm | 6 | |
| Sept. 5 |  Sunny | 28° /16° | 0 mm | 6 | |
| Sept. 6 | Overcast | 23° /12° | 0 mm | 4 | |
| Sept. 7 | Sunny | 24° /10° | 0 mm | 4 | |
| Sept. 8 | Cloudy | 28° /13° | 0 mm | 4 | |
| Sept. 9 | Overcast | 28° /16° | 207.8 mm | 5 | |
| Sept. 10 |  Thundery outbreaks possible | 26° /14° | 0 mm | 7 | |
| Sept. 11 | Fog | 27° /13° | 0 mm | 7 | |
| Sept. 12 | Mist | 28° /15° | 0 mm | 6 | |
| Sept. 13 | Thundery outbreaks possible | 28° /17° | 2 mm | 6 | |
| Sept. 14 | Thundery outbreaks possible | 29° /16° | 0.8 mm | 5 | |
| Sept. 15 | Fog | 26° /18° | 21.8 mm | 4 | |
| Sept. 16 |  Light rain shower | 25° /16° | 5.5 mm | 4 | |
| Sept. 17 | Sunny | 28° /16° | 4.5 mm | 5 | |
| Sept. 18 | Cloudy | 26° /17° | 2.1 mm | 4 | |
| Sept. 19 | Moderate or heavy rain shower | 26° /17° | 26.4 mm | 4 | |
| Sept. 20 | Patchy rain possible | 20° /14° | 10 mm | 1 | |
| Sept. 21 | Patchy rain possible | 14° /11° | 3.6 mm | 1.3 | |
| Sept. 22 | Light rain shower | 14° /10° | 7 mm | 3.5 | |
| Sept. 23 | Sunny | 19° /9° | 0 mm | 5.7 | |
| Sept. 24 | Overcast | 18° /12° | 0.3 mm | 4 | |
| Sept. 25 | Sunny | 20° /14° | 3.4 mm | 6 | |
| Sept. 26 | Sunny | 21° /13° | 0.1 mm | 5 | |
| Sept. 27 | Overcast | 22° /17° | 0 mm | 6 | |
| Sept. 28 | Overcast | 19° /7° | 8.2 mm | 2 | |
| Sept. 29 | Sunny | 13° /5° | 0 mm | 4 | |
| Sept. 30 | Sunny | 15° /9° | 0.3 mm | 4 | |
| Next | |||||
Important Notice
Our weather forecast for Linn 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 Linn County forecast closer to your planned date for the most up-to-date weather information.
Change Month
Linn County in September - FAQ
What are the expected maximum and minimum temperatures in Linn County during September?
Enjoy moderate daytime temperatures of up to 26° and cooler nights around 14°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Linn County during September?
Significant rainfall exceeding 129.1 mm is expected in Linn County during September, occurring over more than 4 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Linn County during September?
The average wind speed in Linn County during September is 16 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Linn County
Explore the daily rainfall trends and prepare for Linn Countys September weather 💧
Typically, Linn County has 4 rainy days in September with a total of 129.1 mm of rainfall.
UV exposure in Linn County during September
Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
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Where is Linn County?Get accurate weather forecasts for Linn County, located at latitude 42.008 and longitude -91.644. Stay updated with localized weather information tailored for Linn County.
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