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Weather in Wyoming for September 2026

Your guide to Wyoming weather in September - trends and predictions

    Snow Forecast ❄️

  • With an average of 3 snowy days, Wyoming usually enjoys a light touch of snow in September.
    According to Wyoming snow forecast for September 2026, 2 snowy days are expected until the end of the month. The closest date with snow is Monday, September 28.

    • Temperatures

  • Until now, September 2026 in Wyoming is slightly cooler than the historical average by 1.5 °F.

  • The forecast for the upcoming days in Wyoming predicts a temperature of 15.3 °F, which is slightly above the historical average.

  • In general, the average temperature in Wyoming at the beginning of September is 20.1 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 13.7 °F by the end of September.

    • Rain 🌧️

  • Wyoming experiences moderate rainfall in September, with an average of 6 rainy days and a total precipitation of 71 mm.

    • More

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Average dry days
21
Dry days
Average rainy days
6
Rainy days
Average snowy days
3
Snow days
Average temperatures
17°/5°
Temperatures
Average wind speed
19 km/h
Avg max wind
Average humidity
50 %
Avg humidity

Wyoming Weather September

Move between months or click on a day
August
October
Sun.Mon.Tue.Wed.Thu.Fri.Sat.
1
Sunny
21°
2
Patchy rain possible
22°
3
Patchy rain possible
19°
4
Sunny
20°
5
Sunny
20°
6
Sunny
21°
7
Partly cloudy
18°
8
Sunny
19°
9
Sunny
19°
10
Overcast
20°
11
Patchy light drizzle
18°
12
Moderate or heavy snow with thunder
13°
13
Moderate or heavy snow showers
12°
14
Sunny
14°
15
Patchy rain possible
14°
16
Patchy rain possible
16°
17
Light rain shower
14°
18
Moderate or heavy rain shower
12°
19
Mist
14°
20
Partly cloudy
14°
21
Partly cloudy
16°
22
Sunny
13°
23
Patchy rain possible
16°
24
Sunny
17°
25
Sunny
18°
26
Partly cloudy
15°
27
Overcast
17°
28
Moderate or heavy snow showers
7°
29
Moderate or heavy snow showers
8°
30
Sunny
14°

What’s the Weather Like in Wyoming This September?

Discover the average temperatures and weather trends across Wyoming’s cities this September.
SunnyYellowstone National Park17 °F / 5 °FSunnyCheyenne24 °F / 10 °FSunnySheridan25 °F / 12 °FSunnyJackson18 °F / 7 °FSunnyCasper25 °F / 9 °FSunnyGrand Teton National Park18 °F / 4 °FMore Locations

Temperatures trend during September in Wyoming

See the weather trend as well as the moving average line

September weather in Wyoming day by day

Click on a date for more information
August October
Date Weather Temperatures Rain Snow More
Sept. 1 Sunny
Sunny
 21° /7° 0.9 mm 0 cm
Sept. 2 Patchy rain possible
Patchy rain possible
 22° /7° 0.1 mm 0 cm
Sept. 3 Patchy rain possible
Patchy rain possible
 19° /8° 0.2 mm 0 cm
Sept. 4 Sunny
Sunny
 20° /7° 0 mm 0 cm
Sept. 5 Sunny
Sunny
 20° /7° 0 mm 0 cm
Sept. 6 Sunny
Sunny
 21° /5° 0 mm 0 cm
Sept. 7 Partly cloudy
Partly cloudy
 18° /7° 1.8 mm 0 cm
Sept. 8 Sunny
Sunny
 19° /4° 0.2 mm 0 cm
Sept. 9 Sunny
Sunny
 19° /5° 0 mm 0 cm
Sept. 10 Overcast
Overcast
 20° /5° 0 mm 0 cm
Sept. 11 Patchy light drizzle
Patchy light drizzle
 18° /6° 1.4 mm 0 cm
Sept. 12 Moderate or heavy snow with thunder
Moderate or heavy snow with thunder
 13° /3° 5.4 mm 1.9 cm
Sept. 13 Moderate or heavy snow showers
Moderate or heavy snow showers
 12° /4° 19.6 mm 0.1 cm
Sept. 14 Sunny
Sunny
 14° /1° 0.8 mm 0 cm
Sept. 15 Patchy rain possible
Patchy rain possible
 14° /3° 0 mm 0 cm
Sept. 16 Patchy rain possible
Patchy rain possible
 16° /4° 0.7 mm 0 cm
Sept. 17 Light rain shower
Light rain shower
 14° /5° 3 mm 0 cm
Sept. 18 Moderate or heavy rain shower
Moderate or heavy rain shower
 12° /2° 14.8 mm 2.9 cm
Sept. 19 Mist
Mist
 14° /4° 3.5 mm 0 cm
Sept. 20 Partly cloudy
Partly cloudy
 14° /3° 1.3 mm 0 cm
Sept. 21 Partly cloudy
Partly cloudy
 16° /4° 1.5 mm 0 cm
Sept. 22 Sunny
Sunny
 13° /2° 2.6 mm 0 cm
Sept. 23 Patchy rain possible
Patchy rain possible
 16° /5° 1.2 mm 0 cm
Sept. 24 Sunny
Sunny
 17° /5° 0 mm 0 cm
Sept. 25 Sunny
Sunny
 18° /6° 0 mm 0 cm
Sept. 26 Partly cloudy
Partly cloudy
 15° /5° 0 mm 0 cm
Sept. 27 Overcast
Overcast
 17° /5° 0.7 mm 0 cm
Sept. 28 Moderate or heavy snow showers
Moderate or heavy snow showers
 7° /2° 5.8 mm 4.2 cm
Sept. 29 Moderate or heavy snow showers
Moderate or heavy snow showers
 8° /1° 2.1 mm 1.5 cm
Sept. 30 Sunny
Sunny
 14° /1° 0 mm 0 cm
Next
Important Notice
Our weather forecast for Wyoming 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 Wyoming forecast closer to your planned date for the most up-to-date weather information.
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Wyoming in September - FAQ

What are the expected maximum and minimum temperatures in Wyoming during September?
Enjoy moderate daytime temperatures of up to 17° and cooler nights around 5°. Ideal for a range of outdoor activities, from hiking to city tours.

How much rainfall should be expected in Wyoming during September?
Moderate rainfall is anticipated in Wyoming during September, with a total of 71 mm spread over approximately 6 days. Considering plans for rainy days is advisable.

Will it snow in Wyoming in September 2026?
Wyoming experiences an average snowfall of 7.4 cm during September, occurring over 3 days.

What are the typical wind conditions in Wyoming during September?
The average wind speed in Wyoming during September is 19 km/h, suggesting breezy to windy conditions, depending on your activities.

Wyoming snow forecast September 2026

Track daily snowfall levels and discover Wyoming’s snowy potential this September ❄️
On average, Wyoming sees 3 snowy days during September, with approximately 7.4 cm of total snowfall.

September rainfall patterns in Wyoming

Explore the daily rainfall trends and prepare for Wyomings September weather 💧
Typically, Wyoming has 6 rainy days in September with a total of 71 mm of rainfall.

UV exposure in Wyoming during September

Stay informed about UV levels for safe outdoor activities throughout the month of September ☀️
Counties in Wyoming
Select a county for an accurate weather forecast
Laramie CountyNatrona CountyPark CountySheridan CountyTeton County
Top locations in Wyoming
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CasperCheyenneGrand Teton National ParkJacksonSheridanYellowstone National Park
More Locations

Quick links

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Location coordinates Where is Wyoming?

Get accurate weather forecasts for Wyoming, located at latitude 44.428 and longitude -110.588. Stay updated with localized weather information tailored for Wyoming.

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