Bolton weather in August

In August, Bolton sees average daytime highs of 25°C and overnight lows near 14°C, with 79 mm of rain across 9.7 wet days and about 13.8 hours of daylight. It is the 2nd-warmest and 4th-wettest month of the year here.

Highs ease over the month, from about 25°C in the first days to 24°C by the end. The sky is clear or mostly clear about 30% of the time in August, and the air most often feels dry.

Daylight stretches from about 14 h 30 min at the start of August to 13 h 06 min by month's end. Set against the rest of the year, August is Bolton's 2nd-clearest and 12th-windiest month. For the whole year in context, see Bolton's year-round climate.

Daytime high
25°
2nd warmest
Overnight low
14°
11th coldest
Rainfall
79 mm
9.7 wet days
Daylight
13 h 48 min
5:28 AM – 7:18 PM
Cloud cover
57%
2nd clearest
Wind
10 km/h
12th windiest
Solar energy
5.3 kWh/m²
Travel score
6.9
out of 10

Bolton is town in Caledon, Ontario, Canada.

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

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 25°C in the first days to 24°C by the end.

A typical August day in Bolton reaches about 25°C in the afternoon and slips back to 14°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 20°C and 29°C. Set against its neighbours, August runs about 1°C cooler than July and about 4°C warmer than September.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12615
22615
32515
42515
52515
62515
72515
82515
92515
102514
112514
122514
132514
142514
152514
162514
172514
182514
192514
202514
212414
222414
232414
242414
252413
262413
272413
282413
292413
302413
312413

How August really feels in Bolton

Once humidity and wind are folded in, August 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

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

Bolton weather by month

How August compares with the rest of the year at a glance. August is the 2nd-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° / -10°569.68.79.10.0
Feb-1° / -10°477.97.210.20.0
Mar / -5°55105.611.60.3
Apr12° / 76112.613.22.8
May18° / 8111.3014.55.6
Jun23° / 12°8811.5015.26.5
Jul26° / 15°8311014.96.6
Aug25° / 14°799.7013.86.9
Sep21° / 10°729.5012.36.5
Oct13° / 73110.410.83.6
Nov / -1°6710.23.59.50.7
Dec / -6°5710.288.80.0

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 30% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 22% of August, with mostly cloudy or overcast conditions the remaining 48%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15347
25347
35347
45347
55347
65347
75248
85248
95248
105248
115248
125248
135248
145248
155248
165248
175149
185149
195149
205248
215248
225149
235248
245248
255347
265347
275446
285446
295347
305347
315446

Chance of precipitation in August

Any precipitation

Bolton gets around 79 mm of rain over 9.7 wet days in August. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 32% and peaks near 37% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
137
236
336
436
536
635
735
835
934
1034
1134
1233
1333
1432
1532
1631
1731
1831
1930
2030
2129
2229
2328
2428
2528
2628
2728
2828
2929
3029
3129

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the dry band about 35% of days. Sticky, muggy-or-worse air turns up on roughly 12% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1283324131
2293224131
3303225131
4303125131
5313125131
6313025131
7323025131
8332925131
9332825121
10342825121
11352825121
12352725121
13352725120
14362826110
15362726110
16362726110
17362826110
18362825110
19362825110
20362825110
21362825110
22362825110
23372824110
24372824100
25382823100
26392823100
27402822100
28402722100
29412721100
30422720100
31432719100

Wind in August

Winds average 10 km/h in August, the calmest month.

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

051015151015202531
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
3010calm
3110calm

Sunrise & sunset in August

DaylightNight

Daylight runs from about 14 h 30 min at the start of August to 13 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 84 minutes over August. Sunrise moves from 5:11 AM to 5:46 AM, and sunset from 7:39 PM to 6:52 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.55:117:39
214.45:127:38
314.45:137:36
414.35:147:35
514.35:167:34
614.35:177:33
714.25:187:31
814.25:197:30
914.15:207:28
1014.15:217:27
1114.15:227:26
1214.05:247:24
1314.05:257:23
1413.95:267:21
1513.95:277:20
1613.85:287:18
1713.85:297:16
1813.75:307:15
1913.75:327:13
2013.65:337:11
2113.65:347:10
2213.65:357:08
2313.55:367:06
2413.55:377:05
2513.45:397:03
2613.45:407:01
2713.35:417:00
2813.35:426:58
2913.25:436:56
3013.25:446:54
3113.15:466:52

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.3 kWh/m².

For context, solar energy here swings from a low near 1.27 kWh/m² to a high of 6.31 kWh/m² in June across the year — August's 5.3 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.8Bright
25.7Bright
35.7Bright
45.7Bright
55.7Bright
65.6Bright
75.6Bright
85.5Bright
95.5Bright
105.5Bright
115.5Bright
125.4Bright
135.4Bright
145.4Bright
155.3Bright
165.3Bright
175.3Bright
185.3Bright
195.2Bright
205.2Bright
215.2Bright
225.1Bright
235.1Bright
245.0Bright
255.0Bright
265.0Bright
274.9Bright
284.9Bright
294.9Bright
304.8Bright
314.8Bright
Planning a trip in August

Is August a good time to visit Bolton?

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

6.9
Sightseeing
1st-best month of the year
6.1
Beach & pool
2nd-best month of the year

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

What to pack for Bolton in August

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

In August, Bolton sees daytime highs around 25°C and nights near 14°C. Worth packing: light clothes, rain gear and sun protection. About 10 days see rain.

light clothesrain gearsun protection

Sea temperature near Bolton in August

The nearest coast averages about 21°C in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 41 km away) is warmest in August at about 21°C and coldest in February near 3°C.

It's comfortable for a long swim from Jul 20 to Sep 2 — about 1.5 months when the water holds above 20°C.

0°10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarm
Sea temperature (°C)Comfort
Jan4Bracing
Feb3Bracing
Mar3Bracing
Apr4Bracing
May7Bracing
Jun15Bracing
Jul20Cool
Aug21Refreshing
Sep19Cool
Oct13Bracing
Nov8Bracing
Dec5Bracing

UV index in Bolton in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August 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 Bolton peaks around June 22 at about 8 (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 8Dec 21UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr5High
May6High
Jun8Very high
Jul8Very high
Aug6High
Sep5High
Oct3Moderate
Nov2Low
Dec1Low

Air quality in Bolton in August

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Bolton is worst in May — around 19 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (November, 9 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodMay 2019 µg/m³Nov 239 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb14Moderate
Mar16Moderate
Apr17Moderate
May19Moderate
Jun18Moderate
Jul18Moderate
Aug16Moderate
Sep14Moderate
Oct10Good
Nov9Good
Dec9Good
Location & terrain

Where is Bolton?

Bolton sits at 43.9°N, 79.7°W, 221 m above sea level, in Canada. The nearest listed city is Mount Olive-Silverstone-Jamestown, 19 km away.

Topography around Bolton

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

Within 3 km, the terrain around Bolton has only modest variations in elevation — a maximum elevation change of 83 m around an average of 249 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 323 m; within 80 km, significant variations in elevation — a maximum elevation change of 473 m.

The land around Bolton is covered by trees (37%) and artificial surfaces (29%) within 3 km, trees (35%), cropland (27%) and grassland (25%) within 16 km, and trees (30%), cropland (29%) and water (21%) within 80 km.

3 km
83 m
16 km
323 m
80 km
473 m
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Mount Olive-Silverstone-Jamestown 19 km · Vaughan 20 km · Caledon 21 km · Humbermede 21 km · West Humber-Clairville 21 km · Black Creek 22 km · Brampton 22 km · Glenfield-Jane Heights 23 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 Bolton (43.8795°, -79.7379°, elevation 221 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. 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).