Cheyenne, WY weather in September
September in Cheyenne: mild, with some rain. Highs 73°F, lows 46°F, rain or snow on about 7 days and about 1.0 in of snow. A great month for outdoor plans.
- Normal high
- 73°F
- Normal low
- 46°F
- Wet days
- 7
- 1.5 in total
- Snowfall
- 1.0 in
- normal snowfall
How September changes from start to finish
| September 1 | September 30 | |
|---|---|---|
| Normal high | 79°F | 66°F |
| Normal low | 51°F | 40°F |
| Chance of a wet day | 28% | 23% |
| Sunrise / sunset | 6:25 am / 7:32 pm | 6:55 am / 6:43 pm |
| Daylight | 13.1 h | 11.8 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Mountain Time).
A typical September day
- 6 am49°Fdew point 37°F
- 9 am63°Fdew point 37°F
- Noon69°Fdew point 35°F
- 3 pm70°Fdew point 35°F
- 6 pm64°Fdew point 37°F
- 9 pm55°Fdew point 39°F
NOAA hourly normals (local standard time) from Cheyenne (1 mi away); average wind 10 mph; clear or few clouds in 70% of daytime hours, mostly cloudy or overcast in 23%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F15 of 30
- Hot dayshigh 90°F or more1 of 30
- Muggy daysdaily mean dew point 65°F or more0 of 30
- Wet daysat least 0.01 in of rain or melted snow7 of 30
- Notable rainat least 0.10 in4 of 30
- Freezing nightslow 32°F or below1 of 30
- Snow on the groundsnow depth 1 in or more0 of 30
Average days per September, counted from daily records for each year 1991-2020.
Rain and snow in September
Normal precipitation is 1.5 in; a dry September brings about 0.5 in and a wet one about 2.0 in (25th and 75th percentiles). About 1 day brings half an inch or more. Normal snowfall is 1.0 in.
How September varies from year to year
- Warmest September, 1991-20202015: average high 80°F
- Coolest September1993: average high 67°F
- Wettest September2013: 7.0 in
- Driest September1992: 0.01 in
- Highest reading95°F (September 2, 2019)
- Lowest reading23°F (September 27, 1996)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
September compared with August and October
| August | September | October | |
|---|---|---|---|
| Normal high | 82°F | 73°F | 59°F |
| Normal low | 54°F | 46°F | 34°F |
| Wet days | 10 | 7 | 7 |
| Comfortable days | 10 | 15 | 12 |
| Daylight | 13.8 h | 12.5 h | 11.1 h |
Highs change by -9°F from August and -14°F into October.
Nearby alternatives in September
- Warmer: Greeley, CO50 mi · high 82°F · 6 wet days
- Cooler: Breckenridge, CO131 mi · high 62°F · 10 wet days
How Cheyenne ranks in September
- Normal high314th warmest of 378 cities; 3rd of 4 in Wyoming
- Wet days170th driest of 378
- Comfortable days68th most of 342
What to pack for Cheyenne in September
- Layers – afternoons near 73°F but nights near 46°F
Heating and cooling
September has 196 heating degree days and 32 cooling degree days (base 65°F), 3% of the year's total heating and cooling demand.
Questions
How hot is Cheyenne in September?
The normal high is 73°F and the normal low is 46°F. From 1991 to 2020 the hottest September reading was 95°F (most recently on September 2, 2019).
Does it rain a lot in Cheyenne in September?
About 7 days in September have at least 0.01 in of precipitation, and the normal total is 1.5 in. The wettest September in 1991-2020 was in 2013 (7.0 in); the driest was in 1992 (0.01 in).
Does it snow in Cheyenne in September?
Yes. Normal snowfall in September is 1.0 in.
Is September a good time to visit Cheyenne?
September ranks 3rd of 12 months on our comfort score for Cheyenne (71 out of 100). It has about 15 comfortable days and about 1 day at 90°F or hotter. The best months are May and June.
Where the numbers come from
- Temperature, rain, snowfall, snow depth, frost dates, humidity and wind by hour and cloud cover: Cheyenne (USW00024018), 1.1 mi NE of the city center, 6,128 ft . NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Cheyenne Airport (725640-24018), 1.4 mi NNE of the city center, 6,118 ft . Hourly observations, 1991-2020.