Montreal in August

In August, Montreal averages 25°C (77°F) during the day and 17°C (63°F) at night, with frequent rain — about 20 days of the month see precipitation (109 mm total).

High season

Conditions are comfortable for sightseeing without being sweltering. Expect daily rain or showers, often in heavy bursts.

August offers comfortable temperatures in Montreal, with some rain to plan around.

25°C
Avg high
17°C
Avg low
20
Rain days
109 mm
Rainfall

How August compares to the rest of the year in Montreal

2nd
warmest month of the 12
2nd
wettest month of the 12
10%
of yearly rainfall falls in August
14 h 8 min
daylight on the 15th

August is one of the warmest months in Montreal (2nd of 12) and one of the wettest months (2nd of 12). Daytime temperature runs 13°C above the annual average (12°C). August runs 1°C cooler than July (26°C) and cools 4°C in September (21°C).

August sunrise & sunset in Montreal

🌅
Sunrise (15th)
5:54 AM
🌇
Sunset (15th)
8:02 PM
Day length
14 h 8 min

Times shown for Montreal local time (America/Montreal), calculated for the 15th of August. They shift by a few minutes day to day across the month.

Photography light in Montreal — August

Golden-hour and blue-hour windows for the 15th of August, in Montreal's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).

🌅 Blue hour (AM)
4:54 AM – 5:34 AM
🌄 Golden hour (AM)
5:34 AM – 6:34 AM
🌇 Golden hour (PM)
7:22 PM – 8:22 PM
🌆 Blue hour (PM)
8:22 PM – 9:02 PM
Milky Way galactic core
Fair
Core only briefly above the horizon — a marginal month even from dark sites near Montreal.

📅 When to book — Montreal in August

Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on August's tier (High season) and Montreal's popularity.

✈ Flights — lead time
3-4 months
Prices are above off-season but not the absolute peak. Tuesday/Wednesday departures are usually cheaper than weekend ones.
🏨 Lodging — lead time
3-5 months
Wide selection still available at this lead time. Premium properties book first; consider 'last-minute deal' availability at 2-week mark if your dates are flexible.

Crowds & pricing — August in Montreal

High season

This is a busy month in Montreal — not the absolute peak, but tourist numbers are clearly elevated. You'll feel it at headline attractions on weekends and in the historic centre, though side streets and lesser-known sights stay manageable. Prices are above off-season but not at their summit. A good week for first-time visitors who want everything open without the worst of the crush.

Why this tier: comfortable tourism weather Northern Hemisphere summer holidays

Sun & mosquito risk — August in Montreal

☀️ UV Index (noon, 15th)
10.5
Very high
Limit sun exposure between 11 AM and 3 PM; SPF 30-50, reapply every 90 minutes outdoors.
🦟 Mosquito risk
●●●●●
Severe
Severe mosquito season with active disease transmission risk. DEET 30%+, picaridin 20%, long sleeves day and night, treated nets, and check CDC/WHO travel advisories before going.

UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.

Montreal in other months

MonthAvg highAvg lowRainfallRain daysSnow days
January -5°C / 23°F -13°C / 8°F 74 mm 17
February -3°C / 26°F -13°C / 9°F 80 mm 17
March 2°C / 36°F -7°C / 20°F 81 mm 18
April 11°C / 51°F 1°C / 33°F 120 mm 17
May 19°C / 67°F 9°C / 47°F 70 mm 16
June 24°C / 74°F 14°C / 58°F 121 mm 19
July 26°C / 79°F 18°C / 64°F 95 mm 20
August 25°C / 77°F 17°C / 63°F 109 mm 20
September 21°C / 70°F 13°C / 55°F 80 mm 14
October 14°C / 57°F 7°C / 44°F 135 mm 18
November 6°C / 42°F -1°C / 30°F 80 mm 17
December 0°C / 31°F -7°C / 19°F 91 mm 16

Other cities with similar August weather

🌍 See the full ranked list of climate twins for Montreal in August →

Frequently asked questions

How hot is Montreal in August?

In August, Montreal averages a high of 25°C (77°F) and a low of 17°C (63°F) — generally warm.

Does it rain a lot in Montreal in August?

August is quite rainy in Montreal, with about 20 rainy days on average.

Is August a good time to visit Montreal?

August is warm but on the rainy side. It suits travelers who are comfortable with warm weather; check the month-by-month ranking to compare it against the rest of the year.

What should I pack for Montreal in August?

Pack light layers for warm days and cooler evenings, plus a compact umbrella or rain jacket. See the full August packing list for Montreal for a complete, climate-based checklist.

Open Montreal on the interactive map

Check the live 10-day forecast and sunrise/sunset.