Last updated: April 22, 2025
August in Montreal, Canada, offers a vibrant summer experience with maximum temperatures reaching 33°C (92°F), making it a perfect time for outdoor activities. The average temperature hovers around a comfortable 21°C (70°F), while the cool nights can dip to a refreshing 8°C (47°F). Although the month sees 109 mm (4.3 in) of rainfall over 13 days, the humidity levels are relatively high at 75%, adding a tropical feel to the city's atmosphere. Whether exploring urban parks or enjoying festival events, August provides a dynamic blend of warmth and excitement for residents and visitors alike.
August in Montreal ushers in a warm embrace as summer reaches its peak. With minimum temperatures around 8°C (47°F) and maximums soaring to an inviting 33°C (92°F), the city buzzes with life under the sun. The average temperature hovers at a comfortable 21°C (70°F), making it an ideal time for outdoor activities, festivals, and enjoying the vibrant cityscape. As the days grow longer, the warmth creates an energetic atmosphere, allowing residents and visitors alike to relish the last golden days of summer before the cooler fall breezes set in. This blend of warmth and activity underlines August as a celebrated chapter in Montreal's climatic calendar.
August in Montreal marks a notable increase in precipitation, with an average of 109 mm (4.3 in) falling over 13 days. This uptick follows a relatively consistent pattern from the summer months of June and July, both recording 103 mm (4.1 in) of rainfall. The city transitions into late summer with slightly more rainfall than in the preceding months, suggesting a shift towards the wetter autumn season that looms ahead. As the air begins to cool, August's precipitation serves as a reminder of nature's rhythm, bridging the warm vibrancy of summer with the impending crispness of fall.
In Montreal, Canada, August brings a slight drop in humidity levels, averaging around 75%. This shift marks a transition from the summer's more humid months, with July peaking at 76%. As the warm season winds down, the humidity in August begins to align more closely with the drier conditions of early fall, where September sees a slight uptick to 78%. Overall, throughout the year, humidity in Montreal tends to be highest during the winter months, often exceeding 90% in January and February, creating a stark contrast to the more moderate levels experienced in late summer.
In August, Montreal experiences a UV Index of 8, maintaining a status of very high exposure, similar to July. This trend underscores the summer's peak, where the sun's rays are particularly potent. With a burn time of just 15 minutes, it's essential for residents and visitors alike to take precautions when enjoying the outdoors. As summer gradually transitions into fall, September sees a slight decrease to a UV Index of 7, indicating a shift towards safer sun exposure but still highlighting the importance of sun safety. For those planning outdoor activities, staying informed about UV levels is crucial. Learn more about the UV Index in Montreal here: Montreal UV Index.
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In Montreal, the month of August enjoys a delightful bounty of sunshine, with 326 hours of bright daylight illuminating the city. As summer reaches its zenith, August’s radiant hours follow a crescendo of sunshine that begins in the spring. Notably, the trend shows a remarkable build-up from February’s modest 155 hours to an impressive peak in July, where the sun graces Montreal for 342 hours. Though August sees a slight dip from July, it still offers an abundance of sunshine, maintaining a vibrant atmosphere as the city prepares for a transition into the cooler months. This seasonal progression highlights the contrast of light, from the dim winter months to the vivid Summer, emphasizing how August stands out as a true summer haven.
August in Montreal shines with a 45% chance of sunny weather, making it one of the bright spots in the city's annual climate. This uptick in sunshine follows a summer trend, as July shows a lower 33% likelihood, suggesting that the days are indeed getting longer and brighter as the season peaks. Compared to the cooler months, where the chance of sun hovers below 40%, August provides a refreshing increase in sunshine, making it an ideal time for outdoor adventures. As summer transitions into fall, it's a perfect opportunity to soak up the sun before the cloudier days ahead.
In August, Montreal basks in approximately 14 hours of daylight, marking a gradual transition as summer begins to wane. This month retains the vibrant energy of July’s longer days, offering residents and visitors ample time to enjoy outdoor activities. Notably, the trend of increasing daylight hours starts in January with only 9 hours, peaking in June and July at 15 hours. As the season shifts toward autumn, daylight hours begin to decrease, setting the stage for the colder months ahead. By September, daylight drops to 12 hours, hinting at nature's impending quiet as summer gives way to fall.
In Montreal, August brings a gentle breeze, with average wind speeds settling at 3.0 m/s (7 mph), consistent with the tranquility of late summer. As the year unfolds, a noticeable pattern emerges: winter months tend to have slightly higher wind speeds, likely due to the chillier temperatures that invigorate the air. Notably, March experiences the briskest winds at 4.5 m/s (10 mph), while the calmest months, July and August, offer a respite at 3.0 m/s (7 mph). This rhythmic dance of wind throughout the seasons highlights August as a time of relaxed breezes, perfect for leisurely strolls along the city's vibrant streets, just as the summer heat begins to wane.
The weather in Montreal changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of August's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Montreal and find detailed weather information for every month.
August and January present stark contrasts in weather. In August, temperatures range from a minimum of 8°C (47°F) to a pleasant average of 21°C (70°F), peaking at a sizzling 33°C (92°F), accompanied by a relatively high humidity level of 75%. The month also sees significant rainfall, with 109 mm (4.3 in) over 13 days. In contrast, January is marked by frigid conditions, with temperatures plummeting to a minimum of -32°C (-25°F) and averaging -8°C (17°F), while reaching a maximum of just 9°C (49°F). This month experiences lower precipitation at 84 mm (3.3 in) over 11 days, but the humidity is notably higher at 93%. For those interested in a deeper dive into January conditions, check out Montreal weather in January.
The weather in August and February presents a stark contrast in Montreal. In August, temperatures range from a minimum of 8°C (47°F) to a maximum of 33°C (92°F), with an average of 21°C (70°F) and higher humidity at 75%. This month also sees precipitation of 109 mm (4.3 in) over approximately 13 days, making it feel quite warm and often muggy. In contrast, February experiences much colder temperatures, with a minimum of -25°C (-13°F) and a maximum of 13°C (56°F), averaging -7°C (20°F). Although February has slightly less precipitation at 82 mm (3.2 in) over 12 days, the humidity is higher at 92%, contributing to a biting chill. For more details on the specifics of winter weather, you can refer to Montreal weather in February.
August and March present strikingly different weather patterns. In August, temperatures range from a cool 8°C (47°F) at night to a warm 33°C (92°F) during the day, with an average of 21°C (70°F). The month experiences significant rainfall, with 109 mm (4.3 in) over 13 days and humidity hovering around 75%. In contrast, March is marked by much colder temperatures, launching from a frigid low of -23°C (-9°F) to a milder maximum of 20°C (69°F), averaging a chilly -2°C (29°F). Precipitation is lower in March, with 84 mm (3.3 in) falling across 11 days, but the humidity is slightly higher at 86%. To explore more about March's weather, you can check Montreal weather in March.
When comparing the weather in August and April, the differences are quite pronounced. August features warmer temperatures, with averages around 21°C (70°F) and a maximum of 33°C (92°F), while April's average temperature is significantly lower at 6°C (43°F), peaking at 25°C (78°F). Despite April's chill, it experiences slightly higher humidity at 85%, compared to August's 75%. Precipitation isn't drastically different, with August receiving 109 mm (4.3 in) over 13 days and April slightly more at 121 mm (4.7 in) over 12 days. For a more detailed look at April's climate, check Montreal weather in April.
The weather in August is generally warmer than in May, with average temperatures in August reaching up to 21°C (70°F), compared to May's average of 14°C (57°F). While both months experience significant humidity—with August at 75% and May slightly higher at 80%—May can still present some surprising highs, with maximum temperatures occasionally peaking at 36°C (97°F). Precipitation levels are quite similar, with August receiving about 109 mm (4.3 in) over 13 days, and May slightly less at 97 mm (3.8 in) over 11 days. For a closer look at what to expect in May, you can check out Montreal weather in May.
In comparing the weather between June and August, we see some notable differences. August typically has a wider temperature range, with minimums around 8°C (47°F) and maximums reaching up to 33°C (92°F), compared to June's lower minimum of 3°C (38°F) and maximum of 34°C (94°F). While August has an average temperature of 21°C (70°F), June sits just slightly below at an average of 19°C (67°F). Precipitation levels are quite similar, with August seeing 109 mm (4.3 in) over 13 days and June recording 103 mm (4.1 in) over 12 days. The humidity is comparable, with August at 75% and June at 74%. For more detailed insights, you can check Montreal weather in June.
In comparing the weather between July and August, we find that August experiences slightly cooler temperatures, with a minimum of 8°C and a maximum of 33°C, compared to July’s minimum of 10°C and maximum of 35°C. The average temperature in August is 21°C, just a degree lower than July’s average of 22°C. Precipitation levels are quite similar, with August recording 109 mm over 13 days and July at 103 mm over 14 days. Humidity remains high in both months, with August at 75% and July slightly higher at 76%. For a detailed look at July's weather, you can check out Montreal weather in July.
August weather tends to be warmer than September, with temperatures ranging from a minimum of 8°C (47°F) to an average of 21°C (70°F) and peaking at 33°C (92°F). In contrast, September sees a drop in average temperature to 16°C (62°F), with minimum temperatures reaching as low as 2°C (35°F) and maximums around 32°C (90°F). Precipitation levels also differ; August experiences more rain, totaling 109 mm (4.3 in) over 13 days, while September has a total of 73 mm (2.9 in) across 9 days. Notably, humidity is slightly higher in September at 78% compared to August’s 75%. For more detailed insights, you can explore Montreal weather in September.
August and October present distinct weather contrasts. August typically enjoys warmer temperatures, with a minimum of 8°C (47°F) and averages around 21°C (70°F), peaking at 33°C (92°F). In comparison, October sees a considerable drop in temperatures, with a minimum dipping to -4°C (25°F) and an average of just 10°C (50°F), although it can still reach up to 27°C (80°F) on milder days. Both months experience similar precipitation days—around 13—but October has slightly higher overall rainfall at 139 mm (5.5 in) compared to August's 109 mm (4.3 in). Additionally, October's humidity is higher at 86%, creating a chillier atmosphere compared to August's 75%. For more details on October's weather, you can check Montreal weather in October.
August and November present stark contrasts in weather conditions. In August, temperatures range from a minimum of 8°C (47°F) to a maximum of 33°C (92°F), averaging around 21°C (70°F). The month experiences a fair amount of rain, with 109 mm (4.3 in) of precipitation over 13 days and a humidity level of 75%. In comparison, November sees much colder temperatures, with a minimum of -17°C (1°F) and an average temperature of just 2°C (35°F). While the maximum temperature can reach 23°C (73°F), the overall climate is significantly chillier, accompanied by 118 mm (4.6 in) of precipitation and a somewhat higher humidity of 88%. To learn more about what to expect during this time of year, visit Montreal weather in November.
August and December present strikingly different weather conditions. In August, temperatures range from a mild 21°C (70°F) on average, reaching highs of 33°C (92°F), accompanied by a considerable amount of precipitation totaling 109 mm (4.3 in) over 13 days, and humidity levels at 75%. Conversely, December brings a sharp drop in temperatures, with averages of -5°C (24°F) and maximums of 14°C (57°F), alongside much colder minimums of -26°C (-15°F). Precipitation in December is slightly lower at 88 mm (3.5 in) over 12 days, with a higher humidity level of 89%. For a more detailed look at the climate, you can check Montreal weather in December.
As August rolls in, Montreal experiences a notable shift in weather, characterized by warmer temperatures and increased humidity that set it apart from the preceding months. This transitional month often delivers a mix of hot days and cooler nights, offering residents and visitors a taste of late summer vibrancy. While rainfall is frequent, contributing to a total of about 13 rainy days, the warmth encourages a lively atmosphere in the city, perfect for outdoor activities and festivals. Explore more about how the climate shapes the city's unique character throughout the year by visiting Montreal Climate.