Oshawa weather in August

In August, Oshawa sees average daytime highs of 25°C and overnight lows near 15°C, with 80 mm of rain across 10.1 wet days and about 13.8 hours of daylight. It is the 2nd-warmest and 6th-wettest month of the year here.

Highs ease over the month, from about 26°C in the first days to 24°C by the end. The sky is clear or mostly clear about 32% of the time in August, and the air most often feels comfortable.

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 Oshawa's 1st-clearest and 12th-windiest month. For the whole year in context, see Oshawa's year-round climate.

Daytime high
25°
2nd warmest
Overnight low
15°
11th coldest
Rainfall
80 mm
10.1 wet days
Daylight
13 h 48 min
5:25 AM – 7:14 PM
Cloud cover
55%
1st clearest
Wind
11 km/h
12th windiest
Solar energy
5.49 kWh/m²
Travel score
6.9
out of 10

Oshawa is city in Durham Region, Ontario, Canada.

Air quality
Good
PM2.5 6 µg/m³ · 2019
Density
1,204/km²
people per km²
Founded
1850

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 26°C in the first days to 24°C by the end.

A typical August day in Oshawa reaches about 25°C in the afternoon and slips back to 15°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 21°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)
12616
22616
32616
42616
52616
62616
72616
82616
92616
102516
112516
122516
132516
142516
152516
162516
172516
182515
192515
202515
212515
222515
232515
242515
252415
262415
272415
282415
292415
302414
312414

How August really feels in Oshawa

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.

Oshawa weather by month

How August compares with the rest of the year at a glance. August is the 2nd-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan-2° / -10°6510.78.89.10.0
Feb-1° / -10°518.26.710.20.0
Mar / -5°6010.45.511.60.2
Apr11° / 8311.3213.22.8
May18° / 7611014.55.6
Jun23° / 14°8911015.26.6
Jul26° / 16°8410.5014.96.6
Aug25° / 15°8010.1013.86.9
Sep21° / 11°809.1012.36.6
Oct14° / 8311.40.210.83.8
Nov / -0°7310.22.79.50.8
Dec / -6°6710.66.88.80.0

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 32% of the time in August, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 22% of August, with mostly cloudy or overcast conditions the remaining 46%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15149
25149
35149
45248
55248
65347
75347
85347
95347
105446
115446
125446
135545
145545
155545
165545
175545
185545
195545
205545
215545
225545
235545
245545
255545
265545
275545
285545
295545
305545
315545

Chance of precipitation in August

Any precipitation

Oshawa gets around 80 mm of rain over 10.1 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 33% and peaks near 36% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
136
236
336
435
535
635
735
835
935
1035
1135
1234
1334
1434
1534
1633
1733
1833
1932
2032
2131
2231
2330
2430
2530
2629
2729
2829
2928
3028
3128

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the comfortable band about 29% of days. Sticky, muggy-or-worse air turns up on roughly 18% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1212929192
2212929192
3212929192
4222928192
5222928192
6232928192
7232928192
8242828182
9242828182
10252828182
11252827172
12252828172
13262828162
14262828162
15262928162
16262928152
17262928152
18262928152
19262928152
20272928142
21272928142
22272927142
23282927142
24292926142
25292926142
26302925151
27312924141
28322923141
29332923141
30342922141
31352921141

Wind in August

Winds average 11 km/h in August, the calmest month.

Across August, daily wind ranges from about 10 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
111calm
211calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1511calm
1611calm
1711calm
1811calm
1911calm
2011calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2811calm
2911calm
3011calm
3111calm

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 5:08 AM to 5:42 AM, and sunset from 7:35 PM to 6:49 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.55:087:35
214.45:097:34
314.45:107:33
414.35:117:32
514.35:127:30
614.35:137:29
714.25:147:28
814.25:157:26
914.15:167:25
1014.15:187:23
1114.15:197:22
1214.05:207:21
1314.05:217:19
1413.95:227:18
1513.95:237:16
1613.85:257:14
1713.85:267:13
1813.75:277:11
1913.75:287:10
2013.65:297:08
2113.65:307:06
2213.65:327:05
2313.55:337:03
2413.55:347:01
2513.45:356:59
2613.45:366:58
2713.35:376:56
2813.35:396:54
2913.25:406:52
3013.25:416:51
3113.15:426:49

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 5.49 kWh/m².

For context, solar energy here swings from a low near 1.33 kWh/m² to a high of 6.43 kWh/m² in June across the year — August's 5.49 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
16.0Bright
25.9Bright
35.9Bright
45.9Bright
55.8Bright
65.8Bright
75.8Bright
85.7Bright
95.7Bright
105.7Bright
115.7Bright
125.6Bright
135.6Bright
145.5Bright
155.5Bright
165.5Bright
175.5Bright
185.4Bright
195.4Bright
205.3Bright
215.3Bright
225.3Bright
235.2Bright
245.2Bright
255.2Bright
265.1Bright
275.1Bright
285.0Bright
295.0Bright
305.0Bright
314.9Bright
Planning a trip in August

Is August a good time to visit Oshawa?

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
6.2
Beach & pool
2nd-best month of the year

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

What to pack for Oshawa in August

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

In August, Oshawa sees daytime highs around 25°C and nights near 15°C. Worth packing: light clothes, rain gear and sun protection. About 10 days see rain.

light clothesrain gearsun protection

Sea temperature near Oshawa 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 offshore is warmest in August at about 21°C and coldest in March near 3°C.

It's comfortable for a long swim from Jul 27 to Sep 2 — about 1.2 months when the water holds above 20°C.

0°10°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarm
Sea temperature (°C)Comfort
Jan4Bracing
Feb3Bracing
Mar3Bracing
Apr4Bracing
May7Bracing
Jun14Bracing
Jul19Cool
Aug21Refreshing
Sep19Cool
Oct13Bracing
Nov8Bracing
Dec5Bracing

UV index in Oshawa 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 Oshawa peaks around June 20 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. 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 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 20UV 8Dec 21UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr5High
May6High
Jun8Very high
Jul7Very high
Aug6High
Sep5High
Oct3Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Oshawa?

Oshawa sits at 43.9°N, 78.8°W, 105 m above sea level, in Canada. The nearest listed city is Whitby, 7.0 km away.

Topography around Oshawa

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

Within 3 km, the terrain around Oshawa has only modest variations in elevation — a maximum elevation change of 85 m around an average of 111 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 346 m; within 80 km, significant variations in elevation — a maximum elevation change of 394 m.

The land around Oshawa is covered by artificial surfaces (52%) and trees (35%) within 3 km, water (31%) and trees (22%) within 16 km, and water (42%) and trees (24%) within 80 km.

3 km
85 m
16 km
346 m
80 km
394 m
treesgrasslandcroplandartificial surfacesbare terrainwater
August weather nearby: Whitby 7.0 km · Brooklin 11 km · Bowmanville 13 km · Ajax 16 km · Pickering 23 km · Rouge 28 km · West Hill 30 km · Uxbridge 31 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 Oshawa (43.9001°, -78.8496°, elevation 105 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).