Grant County (Moses Lake)
September
Weather in Grant County, Washington for September 2025
Your guide to Grant County weather in September - trends and predictions
In general, the average temperature in Grant County at the beginning of September is 34.7 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 24 °F by the end of September.
Precipitation in Grant County during September is a rare event, with an average of fewer than 2 rainy days.
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Temperatures
Rain 🌧️
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30
Dry days
0
Rainy days
0
Snow days
28°/13°
Temperatures
16 km/h
Avg max wind
42 %
Avg humidity
Grant County Weather September
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Temperatures trend during September in Grant County
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September weather in Grant County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Sept. 1 |  Sunny | 37° /18° | 0 mm | 9 | |
| Sept. 2 |  Overcast | 34° /22° | 0.1 mm | 7 | |
| Sept. 3 | Sunny | 30° /16° | 0 mm | 8 | |
| Sept. 4 | Sunny | 33° /16° | 0 mm | 8 | |
| Sept. 5 | Sunny | 35° /18° | 0 mm | 9 | |
| Sept. 6 | Sunny | 37° /19° | 0 mm | 9 | |
| Sept. 7 |  Partly cloudy | 37° /19° | 0 mm | 9 | |
| Sept. 8 | Partly cloudy | 37° /21° | 0 mm | 9 | |
| Sept. 9 | Partly cloudy | 32° /17° | 0 mm | 8 | |
| Sept. 10 | Overcast | 28° /16° | 0 mm | 6 | |
| Sept. 11 |  Patchy rain possible | 22° /16° | 0.1 mm | 5 | |
| Sept. 12 |  Cloudy | 26° /14° | 0 mm | 6 | |
| Sept. 13 | Sunny | 24° /12° | 0 mm | 6 | |
| Sept. 14 | Patchy rain possible | 25° /13° | 0.8 mm | 6 | |
| Sept. 15 | Patchy rain possible | 23° /12° | 0.4 mm | 5 | |
| Sept. 16 | Partly cloudy | 27° /16° | 0 mm | 7 | |
| Sept. 17 | Cloudy | 24° /10° | 0 mm | 5 | |
| Sept. 18 | Overcast | 26° /10° | 0 mm | 6 | |
| Sept. 19 | Cloudy | 27° /9° | 0 mm | 6 | |
| Sept. 20 | Partly cloudy | 21° /9° | 0 mm | 6 | |
| Sept. 21 | Overcast | 23° /6° | 0 mm | 5 | |
| Sept. 22 | Overcast | 25° /10° | 0 mm | 6 | |
| Sept. 23 | Cloudy | 27° /12° | 0 mm | 6 | |
| Sept. 24 | Sunny | 31° /14° | 0 mm | 8 | |
| Sept. 25 | Overcast | 28° /14° | 0.1 mm | 6 | |
| Sept. 26 | Sunny | 22° /7° | 0 mm | 6 | |
| Sept. 27 | Sunny | 24° /10° | 0 mm | 6 | |
| Sept. 28 | Partly cloudy | 27° /9° | 0 mm | 7 | |
| Sept. 29 | Partly cloudy | 18° /6° | 0 mm | 5 | |
| Sept. 30 | Overcast | 18° /-1° | 0 mm | 4 | |
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Important Notice
Our weather forecast for Grant 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 Grant County forecast closer to your planned date for the most up-to-date weather information.
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Grant County in September - FAQ
What are the expected maximum and minimum temperatures in Grant County during September?
Enjoy moderate daytime temperatures of up to 28° and cooler nights around 13°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Grant County during September?
Rainfall in Grant County during September is rare to nonexistent, with the total expected rainfall being less than 10 mm and approximately 0 days seeing any precipitation. Planning without the concern for rain is generally straightforward during this very dry period.
What are the typical wind conditions in Grant County during September?
The average wind speed in Grant County during September is 16 km/h, suggesting breezy to windy conditions, depending on your activities.
September rainfall patterns in Grant County
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UV exposure in Grant County during September
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Where is Grant County?Get accurate weather forecasts for Grant County, located at latitude 47.13 and longitude -119.278. Stay updated with localized weather information tailored for Grant County.
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