Aiken weather in September

In September, Aiken sees average daytime highs of 85°F and overnight lows near 66°F, with 3.3 in of rain across 9.3 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 8th-wettest month of the year here.

Highs ease over the month, from about 88°F in the first days to 82°F by the end. The sky is clear or mostly clear about 37% of the time in September, and the air most often feels muggy.

Daylight stretches from about 12 h 42 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Aiken's 4th-clearest and 9th-windiest month. For the whole year in context, see Aiken's year-round climate.

Daytime high
85°
4th warmest
Overnight low
66°
9th coldest
Rainfall
3.3 in
9.3 wet days
Daylight
12 h 12 min
6:15 AM – 6:27 PM
Cloud cover
54%
4th clearest
Wind
6 mph
9th windiest
Solar energy
4.68 kWh/m²
Travel score
5.5
out of 10

Aiken is city in South Carolina, United States.

Density
562/km²
people per km²
Founded
1835

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 88°F in the first days to 82°F by the end.

A typical September day in Aiken reaches about 85°F in the afternoon and slips back to 66°F overnight — a 19°F spread between the day's warmth and the night's chill. On most days the high lands between 77°F and 93°F. Set against its neighbours, September runs about 5°F cooler than August and about 9°F warmer than October.

50°60°70°80°90°151015202530
Avg high (°F)Avg low (°F)
18870
28870
38870
48869
58769
68769
78769
88768
98768
108668
118668
128667
138667
148567
158567
168566
178566
188566
198466
208465
218465
228365
238364
248364
258364
268263
278263
288263
298162
308162

How September really feels in Aiken

Once humidity and wind are folded in, September averages 6 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
6
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Aiken 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 daysDaylight (hours)Travel score
Jan57° / 37°3.69.3104.1
Feb60° / 40°3.68.410.85.0
Mar68° / 46°3.88.811.76.6
Apr76° / 54°3.27.912.87.2
May83° / 62°3.09.113.76.0
Jun88° / 70°4.213.614.24.0
Jul91° / 73°4.215.8143.1
Aug90° / 72°4.013.813.23.6
Sep85° / 66°3.39.312.25.5
Oct76° / 55°3.16.711.27.5
Nov66° / 45°2.8710.36.7
Dec59° / 40°3.599.84.7

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 19% of September, with mostly cloudy or overcast conditions the remaining 44%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15347
25347
35446
45446
55446
65545
75644
85644
95644
105743
115842
125842
135842
145842
155842
165743
175743
185743
195743
205743
215644
225644
235644
245743
255743
265743
275743
285743
295743
305743

Chance of precipitation in September

Any precipitation

Aiken gets around 3.3 in of rain over 9.3 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 31% and peaks near 37% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
137
236
335
435
534
634
733
833
932
1032
1132
1231
1331
1430
1530
1630
1730
1830
1929
2029
2129
2229
2329
2428
2528
2627
2726
2826
2926
3025

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the muggy band about 33% of days. Sticky, muggy-or-worse air turns up on roughly 55% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1281634391
2381734381
3391734371
4491834350
54101834330
65101934320
75111935300
86111935290
97112035270
107122035260
118122036240
129122036230
1310122036220
1411132036210
1511132036200
1612142036190
1712142036180
1813142035170
1914142035170
2015152035160
2116152034150
2217152033140
2318152033140
2419162132130
2521162131120
2622162130110
2724162129100
2825172128100
292617212790
302717212690

Wind in September

Winds average 6 mph in September.

Across September, daily wind ranges from about 5 mph on the calmest days to 6 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
15calm
25calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 42 min at the start of September to 11 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 60 minutes over September. Sunrise moves from 6:05 AM to 6:25 AM, and sunset from 6:49 PM to 6:07 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.76:056:49
212.76:056:47
312.76:066:46
412.66:076:44
512.66:076:43
612.66:086:42
712.56:096:40
812.56:106:39
912.56:106:37
1012.46:116:36
1112.46:126:35
1212.36:126:33
1312.36:136:32
1412.36:146:30
1512.26:146:29
1612.26:156:27
1712.26:166:26
1812.16:166:24
1912.16:176:23
2012.16:186:22
2112.06:196:20
2212.06:196:19
2312.06:206:17
2411.96:216:16
2511.96:216:14
2611.86:226:13
2711.86:236:12
2811.86:246:10
2911.76:246:09
3011.76:256:07

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.68 kWh/m².

For context, solar energy here swings from a low near 2.43 kWh/m² to a high of 6.21 kWh/m² in May across the year — September's 4.68 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.1Bright
25.1Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
84.9Bright
94.9Bright
104.9Bright
114.8Bright
124.8Bright
134.8Bright
144.7Bright
154.7Bright
164.7Bright
174.6Bright
184.6Bright
194.6Bright
204.5Bright
214.5Bright
224.5Bright
234.4Bright
244.4Bright
254.4Bright
264.3Bright
274.3Bright
284.3Bright
294.3Bright
304.2Bright
Planning a trip in September

Is September a good time to visit Aiken?

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

5.5
Sightseeing
6th-best month of the year
6.9
Beach & pool
2nd-best month of the year

September is a reasonable time to visit Aiken for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Aiken in September

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

In September, Aiken sees daytime highs around 85°F and nights near 66°F. Pack light clothes. Worth having: rain gear and sun protection. About 9 days see rain.

light clothesrain gearsun protection

UV index in Aiken in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Aiken peaks around June 22 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateJun 22UV 9Dec 20UV 3
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar6High
Apr7High
May8Very high
Jun9Very high
Jul9Very high
Aug9Very high
Sep7Very high
Oct5High
Nov4Moderate
Dec3Moderate

Air quality in Aiken 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 Aiken is worst in July — around 18 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (January, 8 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodJul 1718 µg/m³Jan 108 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb10Good
Mar15Moderate
Apr11Good
May12Moderate
Jun16Moderate
Jul18Moderate
Aug16Moderate
Sep12Good
Oct9Good
Nov9Good
Dec8Good
Location & terrain

Where is Aiken?

Aiken sits at 33.6°N, 81.7°W, 515 ft above sea level, in United States. The nearest listed city is North Augusta, 15 mi away.

Topography around Aiken

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

Within 2 miles, the terrain around Aiken has only modest variations in elevation — a maximum elevation change of 272 ft around an average of 505 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 466 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,175 ft.

The land around Aiken is covered by trees (70%) within 2 miles, trees (71%) and grassland (23%) within 10 miles, and trees (78%) within 50 miles.

2 miles
272 ft
10 miles
466 ft
50 miles
1,175 ft
treesgrasslandcroplandartificial surfaceswater
September weather nearby: North Augusta 15 mi · Augusta 16 mi · Martinez 21 mi · Evans 24 mi · Lexington 40 mi · Seven Oaks 47 mi · West Columbia 48 mi · Saint Andrews 48 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 Aiken (33.5604°, -81.7195°, elevation 515 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).