Ken Caryl weather in September

In September, Ken Caryl sees average daytime highs of 74°F and overnight lows near 46°F, with 1.5 in of precipitation across 6.4 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 8th-wettest month of the year here.

Highs ease over the month, from about 78°F in the first days to 70°F by the end. The sky is clear or mostly clear about 52% of the time in September, and the air most often feels dry.

Daylight stretches from about 12 h 54 min at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Ken Caryl's 4th-clearest and 10th-windiest month. For the whole year in context, see Ken Caryl's year-round climate.

Daytime high
74°
4th warmest
Overnight low
46°
9th coldest
Precipitation
1.5 in
6.4 wet days
Daylight
12 h 18 min
5:47 AM – 6:02 PM
Cloud cover
40%
4th clearest
Wind
5 mph
10th windiest
Solar energy
5.52 kWh/m²
Travel score
7.6
out of 10

Ken Caryl is census-designated place in Jefferson County, Colorado, United States.

Density
1,284/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 78°F in the first days to 70°F by the end.

A typical September day in Ken Caryl reaches about 74°F in the afternoon and slips back to 46°F overnight — a 28°F spread between the day's warmth and the night's chill. On most days the high lands between 61°F and 84°F. Set against its neighbours, September runs about 7°F cooler than August and about 13°F warmer than October.

20°40°60°80°151015202530
Avg high (°F)Avg low (°F)
17951
27951
37851
47851
57850
67750
77749
87649
97649
107648
117548
127548
137547
147447
157446
167446
177346
187345
197345
207244
217244
227244
237143
247143
257143
267042
277042
287042
296941
306941

How September really feels in Ken Caryl

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.

Ken Caryl weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan40° / 14°0.95.35.49.50.0
Feb42° / 16°0.95.75.810.40.3
Mar50° / 23°2.07.86.511.72.4
Apr56° / 29°3.0106.2133.7
May66° / 40°3.512.51.714.15.6
Jun77° / 49°2.39.7014.76.9
Jul83° / 55°2.29.9014.56.1
Aug81° / 54°1.99.4013.66.8
Sep74° / 46°1.56.40.612.37.6
Oct61° / 34°1.76.32.810.95.9
Nov48° / 23°1.25.95.29.82.2
Dec39° / 14°0.94.859.30.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 52% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 21% of September, with mostly cloudy or overcast conditions the remaining 27%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
17327
27327
37228
47228
57228
67228
77327
87327
97327
107327
117327
127327
137327
147327
157327
167426
177426
187426
197426
207525
217426
227426
237426
247426
257426
267426
277426
287426
297327
307327

Chance of precipitation in September

Any precipitationSnow

Ken Caryl gets around 1.5 in of rain and snow over 6.4 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 22% and peaks near 24% on the wettest days, and about 1 day brings snow.

0%10%20%30%151015202530
Rain chance (%)Snow chance (%)
1230
2231
3231
4231
5231
6231
7231
8231
9241
10242
11242
12242
13242
14242
15242
16242
17232
18232
19232
20223
21223
22213
23213
24203
25203
26203
27203
28203
29203
30203

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 99% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)
1991
2991
3991
4991
5991
6991
7991
8991
9991
10991
11991
12991
13991
14991
15991
16991
17991
181000
191000
201000
211000
221000
231000
241000
251000
261000
271000
281000
291000
301000

Wind in September

Winds average 5 mph in September.

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

0246810151015202530
Wind speed (mph)Feels
15calm
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 12 h 54 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 78 minutes over September. Sunrise moves from 5:33 AM to 6:01 AM, and sunset from 6:28 PM to 5:39 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.95:336:28
212.95:346:26
312.85:356:24
412.85:366:23
512.75:376:21
612.75:386:19
712.75:396:18
812.65:396:16
912.65:406:14
1012.55:416:13
1112.55:426:11
1212.45:436:09
1312.45:446:08
1412.35:456:06
1512.35:466:04
1612.35:476:02
1712.25:486:01
1812.25:495:59
1912.15:505:57
2012.15:515:56
2112.05:525:54
2212.05:535:52
2311.95:545:51
2411.95:555:49
2511.95:565:47
2611.85:575:45
2711.85:585:44
2811.75:595:42
2911.76:005:40
3011.66:015:39

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.52 kWh/m².

For context, solar energy here swings from a low near 2.59 kWh/m² to a high of 7.45 kWh/m² in June across the year — September's 5.52 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
16.0Intense
26.0Intense
36.0Bright
45.9Bright
55.9Bright
65.9Bright
75.8Bright
85.8Bright
95.8Bright
105.7Bright
115.7Bright
125.6Bright
135.6Bright
145.6Bright
155.5Bright
165.5Bright
175.5Bright
185.4Bright
195.4Bright
205.3Bright
215.3Bright
225.3Bright
235.2Bright
245.2Bright
255.1Bright
265.1Bright
275.0Bright
285.0Bright
295.0Bright
304.9Bright
Planning a trip in September

Is September a good time to visit Ken Caryl?

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

7.6
Sightseeing
1st-best month of the year
5.8
Beach & pool
4th-best month of the year

September is one of the better times to visit Ken Caryl for general sightseeing.

What to pack for Ken Caryl in September

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

In September, Ken Caryl sees daytime highs around 74°F and nights near 46°F. Worth packing: light clothes, a warm layer and sun protection. About 6 days see rain.

light clothesa warm layersun protection

UV index in Ken Caryl in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 8 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Ken Caryl peaks around July 14 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJul 14UV 11Dec 22UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar7High
Apr7High
May8Very high
Jun11Extreme
Jul11Extreme
Aug10Extreme
Sep8Very high
Oct6High
Nov4Moderate
Dec2Moderate

Air quality in Ken Caryl 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 Ken Caryl is worst in August — around 21 µg/m³ PM2.5 (moderate), about 1.6× the cleanest month (May, 13 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateAug 1620 µg/m³May 1113 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb15Moderate
Mar16Moderate
Apr13Moderate
May13Moderate
Jun14Moderate
Jul14Moderate
Aug21Moderate
Sep13Moderate
Oct15Moderate
Nov15Moderate
Dec16Moderate
Location & terrain

Where is Ken Caryl?

Ken Caryl sits at 39.6°N, 105.1°W, 5,761 ft above sea level, in United States. The nearest listed city is Columbine, 2.5 mi away.

Topography around Ken Caryl

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

Within 2 miles, the terrain around Ken Caryl has significant variations in elevation — a maximum elevation change of 889 ft around an average of 5,709 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,894 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 9,429 ft.

The land around Ken Caryl is covered by artificial surfaces (40%), grassland (37%) and trees (21%) within 2 miles, trees (39%), grassland (35%) and artificial surfaces (23%) within 10 miles, and grassland (45%) and trees (37%) within 50 miles.

2 miles
889 ft
10 miles
3,894 ft
50 miles
9,429 ft
treesgrasslandcroplandartificial surfacesbare terrainwatermoss and lichen
September weather nearby: Columbine 2.5 mi · Dakota Ridge 3.1 mi · Littleton 5.6 mi · Highlands Ranch 7.5 mi · Englewood 8.1 mi · Southglenn 8.7 mi · Lakewood 9.3 mi · Greenwood Village 9.3 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 Ken Caryl (39.5758°, -105.1122°, elevation 5,761 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).