Sheridan weather in September

In September, Sheridan sees average daytime highs of 67°F and overnight lows near 43°F, with 2.2 in of precipitation across 9.1 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 73°F in the first days to 62°F by the end. The sky is clear or mostly clear about 49% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 06 min at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Sheridan's 2nd-clearest and 9th-windiest month. For the whole year in context, see Sheridan's year-round climate.

Daytime high
67°
4th warmest
Overnight low
43°
9th coldest
Precipitation
2.2 in
9.1 wet days
Daylight
12 h 18 min
5:53 AM – 6:11 PM
Cloud cover
43%
2nd clearest
Wind
5 mph
9th windiest
Solar energy
4.86 kWh/m²
Travel score
6.5
out of 10

Sheridan is city in and county seat of Sheridan County, Wyoming, United States.

Density
630/km²
people per km²

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 73°F in the first days to 62°F by the end.

A typical September day in Sheridan reaches about 67°F in the afternoon and slips back to 43°F overnight — a 24°F spread between the day's warmth and the night's chill. On most days the high lands between 53°F and 80°F. Set against its neighbours, September runs about 10°F cooler than August and about 14°F warmer than October.

20°40°60°80°151015202530
Avg high (°F)Avg low (°F)
17448
27448
37348
47347
57247
67246
77146
87146
97045
107045
116944
126944
136844
146843
156743
166743
176642
186642
196642
206541
216541
226440
236440
246440
256340
266339
276239
286239
296138
306138

How September really feels in Sheridan

Once humidity and wind are folded in, September averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Sheridan weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan32° / 14°1.17.88.790.0
Feb34° / 15°1.27.78.610.10.0
Mar43° / 22°2.110.710.111.60.6
Apr50° / 29°3.313.510.813.22.0
May58° / 37°3.914.57.114.64.0
Jun69° / 46°3.014.11.515.35.8
Jul78° / 52°2.011.10.1156.8
Aug77° / 51°1.5100.213.97.1
Sep67° / 43°2.29.12.712.36.5
Oct53° / 32°2.69.67.310.73.3
Nov41° / 21°1.48.27.99.40.4
Dec33° / 14°1.07.38.18.70.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 49% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 34%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
17129
27129
37030
47129
56931
66931
76931
86832
96832
106634
116634
126535
136535
146436
156436
166436
176436
186436
196337
206436
216436
226436
236535
246436
256436
266436
276436
286436
296436
306337

Chance of precipitation in September

Any precipitationSnow

Sheridan gets around 2.2 in of rain and snow over 9.1 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 32% and peaks near 34% on the wettest days, and about 3 days bring snow.

0%10%20%30%40%151015202530
Rain chance (%)Snow chance (%)
1272
2273
3273
4274
5284
6285
7285
8296
9306
10307
11317
12328
13339
14339
153410
163411
173411
183412
193412
203412
213413
223413
233413
243414
253315
263315
273316
283317
293317
303318

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100

Wind in September

Winds average 5 mph in September.

Across September, daily wind ranges from about 4 mph on the calmest days to 5 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
14calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 06 min at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 90 minutes over September. Sunrise moves from 5:35 AM to 6:10 AM, and sunset from 6:40 PM to 5:44 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.15:356:40
213.05:366:39
313.05:376:37
412.95:386:35
512.95:406:33
612.85:416:31
712.85:426:29
812.75:436:27
912.75:446:25
1012.65:466:23
1112.65:476:21
1212.55:486:19
1312.55:496:17
1412.45:506:15
1512.45:526:13
1612.35:536:11
1712.35:546:09
1812.25:556:07
1912.15:576:05
2012.15:586:03
2112.05:596:01
2212.06:006:00
2311.96:025:58
2411.96:035:56
2511.86:045:54
2611.86:055:52
2711.76:075:50
2811.76:085:48
2911.66:095:46
3011.66:105:44

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.86 kWh/m².

For context, solar energy here swings from a low near 1.81 kWh/m² to a high of 7.14 kWh/m² in July across the year — September's 4.86 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.6Bright
25.6Bright
35.5Bright
45.5Bright
55.4Bright
65.3Bright
75.3Bright
85.2Bright
95.2Bright
105.1Bright
115.1Bright
125.0Bright
135.0Bright
144.9Bright
154.8Bright
164.8Bright
174.7Bright
184.7Bright
194.6Bright
204.6Bright
214.5Bright
224.5Bright
234.4Bright
244.4Bright
254.3Bright
264.3Bright
274.2Bright
284.2Bright
294.1Bright
304.1Bright
Planning a trip in September

Is September a good time to visit Sheridan?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.5
Sightseeing
3rd-best month of the year
3.3
Beach & pool
4th-best month of the year

September is a reasonable time to visit Sheridan for sightseeing.

What to pack for Sheridan in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Sheridan sees daytime highs around 67°F and nights near 43°F. Worth packing: a warm layer, rain gear and sun protection. About 9 days see rain.

a warm layerrain gearsun protection

UV index in Sheridan in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Sheridan peaks around June 22 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 22UV 9Dec 21UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar4Moderate
Apr5High
May7High
Jun9Very high
Jul8Very high
Aug7Very high
Sep6High
Oct4Moderate
Nov2Low
Dec1Low

Air quality in Sheridan in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Sheridan is worst in August — around 20 µg/m³ PM2.5 (moderate), about 3.1× the cleanest month (November, 7 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodAug 1320 µg/m³Nov 227 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb8Good
Mar10Good
Apr10Good
May10Good
Jun8Good
Jul18Moderate
Aug20Moderate
Sep15Moderate
Oct15Moderate
Nov7Good
Dec7Good
Location & terrain

Where is Sheridan?

Sheridan sits at 44.8°N, 107.0°W, 3,743 ft above sea level, in United States. The nearest listed city is Gillette, 80 mi away.

Topography around Sheridan

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Sheridan.

Within 2 miles, the terrain around Sheridan has only modest variations in elevation — a maximum elevation change of 341 ft around an average of 3,839 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,355 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 10,069 ft.

The land around Sheridan is covered by grassland (46%) and artificial surfaces (30%) within 2 miles, grassland (88%) within 10 miles, and grassland (73%) and trees (21%) within 50 miles.

2 miles
341 ft
10 miles
1,355 ft
50 miles
10,069 ft
treesgrasslandcroplandartificial surfacesbare terrainmoss and lichen
September weather nearby: Gillette 80 mi · Billings 101 mi · Casper 137 mi · Rapid City 190 mi · Bozeman 208 mi · Dickinson 247 mi · Rexburg 248 mi · Rock Springs 249 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Sheridan (44.7972°, -106.9562°, elevation 3,743 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).