Belleville weather in September

In September, Belleville sees average daytime highs of 21°C and overnight lows near 11°C, with 84 mm of rain across 9.3 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 24°C in the first days to 18°C by the end. The sky is clear or mostly clear about 33% 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 Belleville's 1st-clearest and 9th-windiest month. For the whole year in context, see Belleville's year-round climate.

Daytime high
21°
4th warmest
Overnight low
11°
9th coldest
Rainfall
84 mm
9.3 wet days
Daylight
12 h 18 min
5:55 AM – 6:13 PM
Cloud cover
55%
1st clearest
Wind
11 km/h
9th windiest
Solar energy
4.22 kWh/m²
Travel score
6.6
out of 10

Belleville is city in Ontario, Canada.

Air quality
Good
PM2.5 6 µg/m³ · 2019
Density
206/km²
people per km²
Founded
1789

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 24°C in the first days to 18°C by the end.

A typical September day in Belleville reaches about 21°C in the afternoon and slips back to 11°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 16°C and 26°C. Set against its neighbours, September runs about 4°C cooler than August and about 7°C warmer than October.

10°20°30°151015202530
Avg high (°C)Avg low (°C)
12414
22414
32414
42413
52313
62313
72313
82313
92313
102212
112212
122212
132212
142212
152111
162111
172111
182111
192111
202010
212010
222010
232010
241910
25199
26199
27199
28189
29189
30188

How September really feels in Belleville

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

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
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.

Belleville weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-2° / -11°6810.58.59.10.0
Feb-1° / -10°548.16.610.20.0
Mar / -5°66105.411.60.3
Apr12° / 9011.31.913.22.9
May19° / 7810.3014.55.8
Jun24° / 14°9011015.26.6
Jul26° / 16°8410.90156.5
Aug25° / 15°8410.1013.86.8
Sep21° / 11°849.3012.36.6
Oct14° / 8811.70.210.83.8
Nov / -1°78102.79.40.8
Dec / -6°7410.86.88.70.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 18% of September, with mostly cloudy or overcast conditions the remaining 49%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15347
25347
35446
45347
55347
65347
75446
85347
95347
105347
115248
125347
135347
145347
155347
165248
175248
185248
195248
205248
215149
225050
234951
244951
254852
264852
274852
284753
294654
304654

Chance of precipitation in September

Any precipitation

Belleville gets around 84 mm 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 climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
128
228
328
428
528
629
729
829
929
1030
1130
1230
1330
1430
1530
1630
1731
1831
1931
2032
2132
2232
2333
2433
2534
2635
2736
2836
2937
3037

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 57% of days. Sticky, muggy-or-worse air turns up on roughly 7% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1362722132
2382622122
3392621122
4412621112
5422520112
6442520101
7452419101
847241991
948231991
1051221881
1151221881
1253211871
1354201871
1455201861
1557191761
1659191750
1759191750
1860191650
1962181640
2063181540
2164181530
2266171430
2367171330
2469161320
2570161220
2671161120
2774151010
287515910
297714810
307813810

Wind in September

Winds average 11 km/h in September.

Across September, daily wind ranges from about 10 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
511calm
611calm
711calm
811calm
911calm
1011calm
1111calm
1211calm
1311calm
1411calm
1511calm
1611calm
1711calm
1811calm
1911calm
2011calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2812calm
2912calm
3012calm

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 5:37 AM to 6:12 AM, and sunset from 6:41 PM to 5:46 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.15:376:41
213.05:386:40
313.05:396:38
412.95:416:36
512.95:426:34
612.85:436:32
712.85:446:30
812.75:456:28
912.75:476:26
1012.65:486:24
1112.65:496:23
1212.55:506:21
1312.55:516:19
1412.45:526:17
1512.45:546:15
1612.35:556:13
1712.25:566:11
1812.25:576:09
1912.15:586:07
2012.16:006:05
2112.06:016:03
2212.06:026:01
2311.96:035:59
2411.96:045:57
2511.86:065:55
2611.86:075:54
2711.76:085:52
2811.76:095:50
2911.66:115:48
3011.66:125:46

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.22 kWh/m².

For context, solar energy here swings from a low near 1.31 kWh/m² to a high of 6.38 kWh/m² in June across the year — September's 4.22 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.9Bright
24.9Bright
34.8Bright
44.8Bright
54.7Bright
64.7Bright
74.6Bright
84.6Bright
94.5Bright
104.5Bright
114.5Bright
124.4Bright
134.4Bright
144.3Bright
154.3Bright
164.2Bright
174.2Bright
184.1Bright
194.1Bright
204.0Bright
214.0Moderate
223.9Moderate
233.9Moderate
243.8Moderate
253.7Moderate
263.7Moderate
273.6Moderate
283.6Moderate
293.5Moderate
303.5Moderate
Planning a trip in September

Is September a good time to visit Belleville?

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

6.6
Sightseeing
2nd-best month of the year
4.1
Beach & pool
4th-best month of the year

September is a reasonable time to visit Belleville for sightseeing.

What to pack for Belleville in September

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

In September, Belleville sees daytime highs around 21°C and nights near 11°C. Worth packing: rain gear. About 9 days see rain.

rain gear

Sea temperature near Belleville in September

The nearest coast averages about 20°C 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 21 km away) is warmest in August at about 22°C and coldest in March near 1°C.

It's comfortable for a long swim from Jul 16 to Sep 11 — about 1.9 months when the water holds above 20°C.

0°10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan3Bracing
Feb1Bracing
Mar1Bracing
Apr3Bracing
May7Bracing
Jun14Bracing
Jul20Refreshing
Aug22Refreshing
Sep20Cool
Oct15Bracing
Nov10Bracing
Dec6Bracing

UV index in Belleville 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 Belleville peaks around July 11 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 22 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 11UV 8Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr5Moderate
May7High
Jun8Very high
Jul8Very high
Aug6High
Sep6High
Oct3Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Belleville?

Belleville sits at 44.2°N, 77.4°W, 93 m above sea level, in Canada. The nearest listed city is Quinte West, 15 km away.

Topography around Belleville

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Belleville.

Within 3 km, the terrain around Belleville has only modest variations in elevation — a maximum elevation change of 38 m around an average of 88 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 194 m; within 80 km, significant variations in elevation — a maximum elevation change of 355 m.

The land around Belleville is covered by artificial surfaces (35%), water (24%) and trees (21%) within 3 km, trees (38%), grassland (25%) and cropland (21%) within 16 km, and trees (40%) and water (40%) within 80 km.

3 km
38 m
16 km
194 m
80 km
355 m
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Quinte West 15 km · Prince Edward 21 km · Greater Napanee 36 km · Cobourg 67 km · Kingston 72 km · Peterborough 76 km · Oswego 106 km · Irondequoit 107 km

Canada travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 83% of US
price level, 2025
GDP per capita
$55,698
2025
Happiness
6.7 / 10
World Happiness, 2025
Safe drinking water
97%
of population, 2024
Homicide rate
2
per 100k, 2023
Road deaths
5.3
per 100k/yr, 2019
Income group
High
World Bank
Religion
Christian 53%none 35%Muslim 5%Hindu 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 Belleville (44.1668°, -77.3828°, elevation 93 m), 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. 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).