Bel Air South weather in September

In September, Bel Air South sees average daytime highs of 76°F and overnight lows near 62°F, with 4.4 in of rain across 9.2 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 1st-wettest month of the year here.

Highs ease over the month, from about 80°F in the first days to 72°F by the end. The sky is clear or mostly clear about 38% 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 Bel Air South's 2nd-clearest and 9th-windiest month. For the whole year in context, see Bel Air South's year-round climate.

Daytime high
76°
4th warmest
Overnight low
62°
9th coldest
Rainfall
4.4 in
9.2 wet days
Daylight
12 h 18 min
5:52 AM – 6:07 PM
Cloud cover
55%
2nd clearest
Wind
6 mph
9th windiest
Solar energy
4.27 kWh/m²
Travel score
7.0
out of 10

Bel Air South is census-designated place in Harford County, Maryland, United States.

Density
1,169/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 80°F in the first days to 72°F by the end.

A typical September day in Bel Air South reaches about 76°F in the afternoon and slips back to 62°F overnight — a 14°F spread between the day's warmth and the night's chill. On most days the high lands between 68°F and 84°F. Set against its neighbours, September runs about 6°F cooler than August and about 11°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
18167
28167
38067
48066
58066
68066
77965
87965
97965
107864
117864
127864
137763
147763
157663
167662
177662
187662
197561
207561
217460
227460
237460
247359
257359
267359
277258
287258
297258
307157

How September really feels in Bel Air South

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.

Bel Air South weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan40° / 29°3.18.63.19.50.1
Feb43° / 30°2.88.93.210.40.5
Mar51° / 37°4.010.42.111.72.5
Apr63° / 47°3.510.40.2135.3
May72° / 57°3.410.7014.16.5
Jun81° / 66°3.410.5014.76.2
Jul85° / 71°3.611.1014.55.2
Aug83° / 69°3.59.6013.66.0
Sep76° / 62°4.49.2012.37.0
Oct65° / 51°3.68.30116.2
Nov54° / 41°3.07.60.29.83.5
Dec45° / 33°3.78.91.79.31.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 38% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 15% of September, with mostly cloudy or overcast conditions the remaining 47%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15644
25644
35644
45644
55644
65545
75545
85545
95545
105446
115446
125446
135446
145347
155347
165248
175149
185149
195149
205050
215050
225050
235050
245149
255149
265248
275347
285347
295446
305446

Chance of precipitation in September

Any precipitation

Bel Air South gets around 4.4 in of rain over 9.2 wet days in September, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 29% and peaks near 30% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
128
228
329
429
529
630
730
830
930
1030
1129
1229
1328
1428
1528
1628
1728
1828
1929
2029
2130
2230
2330
2430
2530
2630
2730
2830
2930
3030

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 31% of days. Sticky, muggy-or-worse air turns up on roughly 30% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
114152526191
215152525191
316152524181
417162523181
518162523171
619172522171
720172521161
821182421151
922182420141
1023182420141
1125192320131
1226192320120
1327192220110
1428192220100
152919222090
163119212080
173219212070
183320212060
193420202050
203520202050
213720202040
223820192040
233919191930
244119181930
254219181820
264419181820
274519181720
284718171610
294818171510
305018171510

Wind in September

Winds average 6 mph in September.

Across September, daily wind ranges from about 6 mph on the calmest days to 7 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

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 5:38 AM to 6:06 AM, and sunset from 6:32 PM to 5:44 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.95:386:32
212.95:396:31
312.85:406:29
412.85:416:27
512.75:426:26
612.75:426:24
712.75:436:22
812.65:446:21
912.65:456:19
1012.55:466:17
1112.55:476:16
1212.45:486:14
1312.45:496:12
1412.35:506:11
1512.35:516:09
1612.35:526:07
1712.25:536:06
1812.25:546:04
1912.15:556:02
2012.15:566:00
2112.05:575:59
2212.05:585:57
2311.95:595:55
2411.96:005:54
2511.96:015:52
2611.86:025:50
2711.86:035:49
2811.76:045:47
2911.76:055:45
3011.66:065:44

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.27 kWh/m².

For context, solar energy here swings from a low near 1.88 kWh/m² to a high of 6.09 kWh/m² in June across the year — September's 4.27 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.8Bright
24.8Bright
34.8Bright
44.7Bright
54.7Bright
64.7Bright
74.6Bright
84.6Bright
94.5Bright
104.5Bright
114.5Bright
124.4Bright
134.4Bright
144.4Bright
154.3Bright
164.3Bright
174.2Bright
184.2Bright
194.2Bright
204.1Bright
214.1Bright
224.0Bright
234.0Bright
244.0Moderate
253.9Moderate
263.9Moderate
273.9Moderate
283.8Moderate
293.8Moderate
303.8Moderate
Planning a trip in September

Hazard calendar for Bel Air South

In seasonPeak

In September, Bel Air South sits inside its atlantic hurricane season. The full year is below, with each hazard's peak months called out.

Bel Air South sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Bel Air South?

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

7.0
Sightseeing
1st-best month of the year
6.1
Beach & pool
4th-best month of the year

September is one of the better times to visit Bel Air South for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Bel Air South in September

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

In September, Bel Air South sees daytime highs around 76°F and nights near 62°F. Worth packing: light clothes and rain gear. About 9 days see rain.

light clothesrain gear

Sea temperature near Bel Air South in September

The nearest coast averages about 74°F in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 27 mi away) is warmest in August at about 78°F and coldest in February near 36°F.

It's comfortable for a long swim from Jun 16 to Oct 5 — about 3.7 months when the water holds above 68°F.

30°40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan38Bracing
Feb36Bracing
Mar40Bracing
Apr47Bracing
May58Bracing
Jun68Refreshing
Jul76Warm
Aug78Warm
Sep74Refreshing
Oct65Cool
Nov53Bracing
Dec44Bracing

UV index in Bel Air South 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 Bel Air South peaks around July 10 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateLowJul 10UV 9Dec 20UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug6High
Sep6High
Oct4Moderate
Nov3Moderate
Dec2Low

Air quality in Bel Air South 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 Bel Air South is worst in July — around 17 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (November, 8 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1417 µg/m³Nov 138 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb12Good
Mar13Moderate
Apr13Moderate
May15Moderate
Jun16Moderate
Jul17Moderate
Aug15Moderate
Sep12Good
Oct9Good
Nov8Good
Dec9Good
Location & terrain

Where is Bel Air South?

Bel Air South sits at 39.5°N, 76.3°W, 325 ft above sea level, in United States. The nearest listed city is South Bel Air, 1.9 mi away.

Topography around Bel Air South

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

Within 2 miles, the terrain around Bel Air South has only modest variations in elevation — a maximum elevation change of 384 ft around an average of 292 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 689 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,388 ft.

The land around Bel Air South is covered by trees (71%) within 2 miles, trees (60%) and grassland (21%) within 10 miles, and trees (46%) and cropland (21%) within 50 miles.

2 miles
384 ft
10 miles
689 ft
50 miles
1,388 ft
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: South Bel Air 1.9 mi · North Bel Air 3.1 mi · Bel Air North 4.3 mi · Edgewood 6.2 mi · Aberdeen 8.1 mi · Perry Hall 9.9 mi · Carney 13 mi · Middle River 14 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 Bel Air South (39.5051°, -76.3198°, elevation 325 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).