Last updated: February 24, 2025
In August, Boston experiences a dynamic blend of summer warmth and sporadic rainfall. With maximum temperatures soaring to 31°C (88°F), the city invites both locals and tourists to relish in its vibrant atmosphere. The average temperature settles comfortably at 21°C (70°F), while nighttime lows can dip to a brisk 8°C (47°F), reminding residents of the approaching fall. This month sees approximately 85 mm (3.3 in) of precipitation over 13 days, contributing to a humidity level of 72% that adds a touch of mugginess to the summer air. Whether basking in the sun or savoring the refreshing showers, August in Boston offers an eclectic mix of climatic experiences.
In August, Boston basks in a warm embrace, with temperatures marked by a minimum of 8°C (47°F), an average of 21°C (70°F), and a maximum of 31°C (88°F). This trend of rising warmth continues from the hotter July, providing a perfect backdrop for summer activities. The warmth makes it an ideal month for outdoor adventures, from strolling along the Charles River to enjoying local festivals. As the city transitions towards fall, August represents the pinnacle of New England summer, inviting both residents and visitors to savor the pleasant weather before the cooler months set in.
In August, Boston experiences a moderate precipitation amount of 85 mm (3.3 in), slightly lower than the deluges of July, which recorded 127 mm (5.0 in). This month typically sees around 13 days of rain, contributing to a relatively dry backdrop as summer winds down. Despite the decrease in precipitation, August still maintains a consistent rhythm in Boston's yearly weather patterns, which crescendo in the preceding months, particularly from April through July. As autumn approaches, the precipitation trend shifts downward, with September averaging just 76 mm (3.0 in) over 9 rainy days, heralding a transition to the drier fall months ahead.
In August, Boston experiences a notable drop in humidity, with levels at 72%, making it one of the driest months of the year. This decrease follows a gradual decline from the peak summer months, as July boasts humidity levels at 77%. Interestingly, this shift towards lower humidity reflects a broader trend as the city transitions from the sweltering summer into the refreshing early fall. In contrast, the winter months begin with high humidity, around 91%, creating a yearly cycle where moisture levels ebb and flow dramatically. This August reprieve not only provides greater comfort for Bostonians but also marks a subtle shift towards refreshing autumnal days ahead.
In August, Boston experiences a notably high UV Index of 9, categorizing it as very high, which means sunburn can occur in as little as 15 minutes of unprotected exposure. This peak reflects a trend seen throughout the summer months, where both June and July also recorded an Index of 10, prompting caution for outdoor enthusiasts. As summer transitions into fall, the UV Index starts to decline, with September seeing a drop to 8, but the risk remains significant. With this persistent high UV exposure, it's essential to stay sun-safe and be mindful of the sun's intensity during these months. For more insights on UV trends, visit Boston UV Index.
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August in Boston is a shining peak of summer, basking in 338 hours of sunshine—tying with July for the sunniest month of the year. This vibrant month marks the conclusion of a steady climb from the 91 hours of light in January to an impressive peak in mid-summer. As spring transitions into summer, sunshine significantly increases, culminating in those long, bright days when Bostonians take to parks and waterfronts to soak up the warmth. The trend then gently dips into September, bringing 293 hours of sunlight, signaling the start of autumn while still retaining a generous amount of sun. Overall, the monthly sunshine showcases a delightful pattern: a gradual ascent toward summer brilliance followed by a graceful descent into fall's embrace.
In August, Boston enjoys a 42% chance of sunny weather, making it one of the brighter months of the year. As we observe the trend, it becomes clear that sunshine opportunities begin to rise significantly in the spring, with March starting at 43% and peaking during the summer months. From June's 45% down to 38% in July, August maintains a solid percentage of sunshine, closely aligning with September's 41%. This consistency emphasizes that while summer days can occasionally be hazy, August remains a favorable time for sunny adventures in the city, as it sits comfortably amid a generally upward trend in sunshine from late winter through summer.
In August, Boston enjoys a robust 13 hours of daylight, marking a subtle decline from the peak of 15 hours in June. This month serves as a transition, with daylight gradually waning as the city shifts toward the shorter days of fall. The bright summer months of May and June provide a generous bounty of sunlight, fostering vibrant outdoor activities, while August retains a lingering warmth as the daylight begins its slow descent. Following August, daylight dips to 12 hours in September, signaling the approach of autumn and the shortening periods of sunlight that characterize the later months of the year. This gradual shift not only influences daily life in Boston but also invites a reflective transition as summer slowly yields to the cozy embrace of fall.
In August, Boston experiences a notable decline in wind speed, averaging a gentle 2.7 m/s (6 mph)—the calmest of the year. This shift is part of a broader trend where the summer months witness lighter breezes, contrasting with the brisk winds of late autumn and winter. As the city transitions from the sweltering heat of summer to the refreshing breeze of autumn, the winds begin to pick up again in September, returning to 3.5 m/s (8 mph). This August lull offers a serene environment in Boston, perfect for enjoying the vibrant summer scenes before the winds of change usher in the fall season.
The weather in Boston 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 Boston and find detailed weather information for every month.
August and January present strikingly contrasting weather conditions. In August, temperatures range from a mild 8°C (47°F) to a warm 31°C (88°F), with an average around 21°C (70°F). The month experiences 85 mm of precipitation over 13 days, accompanied by a humidity level of 72%, making it a humid summer month. Conversely, January sees much colder temperatures, with a minimum of -21°C (-6°F) and a maximum of 17°C (63°F), averaging -3°C (27°F). The precipitation amount is comparable, at 87 mm over 14 days, but the humidity is slightly higher at 91%, giving January a starkly different, frigid feel. For a more detailed look at January weather specifics, check out Boston weather in January.
Comparing the weather in August and February reveals stark contrasts. In August, temperatures range from a minimum of 8°C (47°F) to a maximum of 31°C (88°F), with an average of 21°C (70°F). Humidity sits at a moderate 72%, and precipitation occurs on about 13 days, totaling 85 mm (3.3 in). In contrast, February experiences much colder conditions, with temperatures ranging from a frigid minimum of -19°C (-2°F) to a comfortable maximum of 20°C (69°F), averaging -2°C (29°F). Precipitation is slightly higher at 90 mm (3.5 in), but it spreads over 16 days, accompanied by higher humidity at 91%. For more details on February weather specifics, check this link: Boston weather in February.
August and March present two contrasting weather experiences. In August, temperatures are generally milder, ranging from a minimum of 8°C (47°F) to a warm maximum of 31°C (88°F), with an average of 21°C (70°F). However, the month sees considerable humidity at 72% and notable precipitation, totaling 85 mm (3.3 in) over 13 days. In stark contrast, March is much colder, with temperatures dipping as low as -18°C (0°F) and reaching a maximum of 22°C (72°F). The average temperature for March is only 2°C (35°F), and while the precipitation is slightly lower at 80 mm (3.2 in) across the same number of days, humidity is higher at 88%. For more detailed insights into Boston weather in March, you can explore the fluctuations that characterize this transitional month.
Comparing the weather in August and April reveals notable differences in temperature and precipitation patterns. August features a much warmer climate, with average temperatures around 21°C (70°F) and maximums reaching 31°C (88°F), while April presents cooler conditions, averaging just 7°C (45°F) with maximums of 28°C (82°F). However, April experiences slightly higher precipitation, totaling 119 mm (4.7 in) over 15 days, compared to August's 85 mm (3.3 in) over 13 days. Additionally, April has higher humidity levels at 88%, while August's humidity is around 72%. For more detailed insights, you can check Boston weather in April.
When comparing the weather in August and May, we see distinct differences in temperature, precipitation, and humidity. August tends to be warmer with average temperatures around 21°C (70°F) and a maximum reaching up to 31°C (88°F), while May experiences a cooler average of 14°C (58°F) and a maximum of 32°C (89°F). Precipitation is slightly higher in May, totaling 107 mm (4.2 in) over 14 days compared to August’s 85 mm (3.3 in) spread over 13 days. Additionally, humidity levels are a bit lower in August at 72% compared to May’s 82%. For more specific insights into May weather, you can check the details at Boston weather in May.
In comparing the weather between June and August, June tends to be slightly cooler with an average temperature of 19°C (67°F), while August boasts a warmer average of 21°C (70°F). August experiences a wider temperature range, with minimums at 8°C (47°F) and maximums reaching up to 31°C (88°F), in contrast to June's more moderate minimum of 5°C (42°F) and maximum of 32°C (90°F). Precipitation levels are quite similar in both months, with June seeing 89 mm (3.5 in) over 12 days and August having 85 mm (3.3 in) over 13 days. Humidity is slightly higher in August at 72%, compared to June’s 79%, making both months feel relatively humid. For more insights into June weather, you can check Boston weather in June.
In comparing the weather of August and July, we see a notable shift in temperatures and precipitation levels. August starts off cooler, with minimum temperatures dropping to 8°C (47°F) and maximums reaching 31°C (88°F), yielding an average of 21°C (70°F). In contrast, July has higher minimum and maximum temperatures of 11°C (52°F) and 33°C (91°F), respectively, resulting in an average of 22°C (72°F). Additionally, July experiences more precipitation, with 127 mm (5.0 in) over 15 days, compared to August's 85 mm (3.3 in) over 13 days. Humidity levels are also slightly higher in July at 77%, compared to 72% in August. For more specific details on July weather, visit Boston weather in July.
August generally experiences warmer temperatures, with an average of 21°C (70°F) and a maximum reaching up to 31°C (88°F). In contrast, September sees a drop in the average temperature to 18°C (64°F) and a minimum of 3°C (38°F), while still maintaining a maximum similar to August at 31°C (89°F). Precipitation levels are relatively close, with August receiving 85 mm (3.3 in) over 13 days and September slightly lower at 76 mm (3.0 in) over just 9 days. Humidity also increases in September to 76%, compared to 72% in August. For more details, check out Boston weather in September.
August tends to be warmer, with average temperatures reaching around 21°C (70°F) and maximums soaring up to 31°C (88°F). The month experiences lower humidity levels at 72%, but sees considerable rainfall, totaling about 85 mm across 13 days. In contrast, October brings a noticeable drop in temperatures, with an average of 12°C (54°F) and a minimum that can dip to 0°C (32°F). This month is also wetter, with total precipitation increasing to 134 mm over 16 days and a rise in humidity to 83%. For more details about the weather in October, you can check Boston weather in October.
August and November present contrasting weather patterns. In August, temperatures range from a mild 8°C (47°F) to a warm 31°C (88°F), with an average of 21°C (70°F) and a relative humidity of 72%. Rainfall is moderate, totaling 85 mm over about 13 days. In stark contrast, November experiences significantly colder temperatures, ranging from a frigid -14°C (8°F) to a maximum of 25°C (77°F), with an average of just 4°C (40°F). Precipitation increases slightly to 99 mm over 15 days, and humidity rises to 88%. For more insights into the weather conditions during this month, visit Boston weather in November.
In August, the weather is generally warm, with temperatures ranging from a minimum of 8°C (47°F) to a maximum of 31°C (88°F), coupled with an average temperature of 21°C (70°F). This month experiences about 85 mm (3.3 in) of precipitation over approximately 13 days, and humidity levels sit at a comfortable 72%. Conversely, December presents a stark contrast, with temperatures plummeting to a minimum of -19°C (-2°F) and a maximum of 18°C (65°F), averaging around 0°C (33°F). The month sees higher precipitation levels of 105 mm (4.1 in) spread over 18 days, and humidity rises to 87%. For more detailed insights into December's weather, visit Boston weather in December.
As summer reaches its peak, August weather in Boston stands out with warm days and cool evenings that contrast with the milder temperatures of the spring and fall months. The muggy conditions, marked by a humidity level of 72%, often lead to occasional rain, with about half the month experiencing some precipitation on average. With daytime highs reaching a sizzling 31°C (88°F), the warmth invites a vibrant outdoor culture, but temperatures can dip significantly at night, making for comfortable evenings. If you're planning a visit or just curious about the variation in climate, explore more about Boston's distinct weather patterns through the link: Boston Climate.