Last updated: March 17, 2025
September in Boston, United Kingdom, offers a delightful blend of warm and cool weather, with maximum temperatures reaching up to 28°C (83°F). The month boasts an average temperature of 15°C (59°F), while nighttime lows can dip to a crisp 4°C (39°F). Although the skies may open up, bringing a total precipitation of 60 mm (2.4 in) over about 10 days, the high humidity levels at 84% can add a sense of warmth to those occasional rainy spells. This dynamic weather paints a vibrant backdrop for exploring the charm of Boston.
As summer transitions into autumn, September in Boston, United Kingdom, offers a delightful blend of warmth and coolness. With minimum temperatures around 4°C (39°F) and a pleasant average of 15°C (59°F), the days are still relatively mild, peaking at a comfortable 28°C (83°F). This month marks a gentle decline from the soaring highs of August, but there’s still plenty of warmth lingering in the air. The shift in temperatures signals the onset of fall, inviting residents and visitors to enjoy crisp mornings and pleasantly warm afternoons. September serves as a beautiful reminder of summer’s final embrace, providing a perfect backdrop for outdoor adventures and scenic strolls through the vibrant surroundings.
September in Boston, United Kingdom, offers a notable shift in precipitation patterns as summer transitions to autumn. With an average rainfall of 60 mm (2.4 in) over about 10 days, the month sees a moderate amount of precipitation, slightly dipping from the higher levels of August, which recorded 80 mm (3.1 in). This decline marks a return to more typical early autumn weather after a wetter summer. The overall trend reveals September as a month of balance—a blend of lingering summer showers giving way to the crispness of fall, as the landscape begins to prepare for the upcoming chill of October, which surprisingly swings back up with 74 mm (2.9 in). This fluctuating pattern reflects the region's dynamic climate, where each month presents its own unique character.
As summer gives way to autumn, September in Boston sees a noticeable shift in humidity levels, rising to 84% after the drier months of July and August, which recorded 79% and 78% respectively. This increase reflects the transition from the warmth of summer into the cooler, more moisture-laden days of fall. Notably, the humidity typically remains elevated leading into October, climbing back to 88%, suggesting a pattern where the humidity tends to rise again as the season changes. Overall, September serves as a bridge between the dryer summer months and the more humid autumn and winter periods, illustrating Boston's characteristic, fluctuating climate.
In September, Boston, United Kingdom, experiences a moderate UV Index of 5, indicating a shift from the peak summer months when UV levels were at their highest. With a burn time of 30 minutes, residents and visitors should remain cautious during outdoor activities, as sun exposure can still lead to skin damage. This month marks a gentle decline from August's UV Index of 7, revealing a trend of decreasing solar intensity as autumn approaches. As the days shorten and the weather cools, it’s important to adapt sun protection strategies accordingly. For detailed insights on UV trends year-round, visit Boston UV Index.
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September in Boston, United Kingdom, brings a gentle transition into autumn, standing out with 286 hours of sunshine. This month, while still basking in the warmth of summer, experiences a noticeable decline from the peak sunshine recorded in the bright days of July and August. As fall approaches, the golden glow begins to wane, yet September still offers a generous amount of light compared to the darker months ahead, such as October and November. The sunlit hours in September provide a perfect backdrop for enjoying the lingering warmth of late summer evenings, beautifully marking a shift in the seasonal palette. This trend showcases how the sun’s embrace gradually lessens, inviting a cozy atmosphere that is quintessentially autumn in Boston.
In September, Boston, United Kingdom, experiences a 29% chance of sunny weather, maintaining a level of sunshine similar to the summer months, albeit a slight dip from July's peak of 36%. As autumn approaches, this trend reflects a subtle shift away from the more vibrant sunlit days of spring, where April enjoys a notable 44% chance of sunshine. The transition into fall is marked by fluctuating sunlight, yet September still holds promise for those seeking to bask in the warmth of outdoor activities. Overall, while the likelihood of sunny weather begins to fade as the year progresses into October and November, September remains a respectable contender for catching those coveted sunny spells.
As September arrives in Boston, UK, daylight begins to gracefully transition from the long, luminous days of summer to the darker months ahead. With approximately 12 hours of daylight, September marks a gentle decline in sunlight compared to August’s 14 hours, but still offers ample time to enjoy the outdoors. This month serves as a bridge, welcoming the autumnal vibe while valiantly holding onto the remnants of summer's brilliance. Following September, the daylight duration continues its downward trend, dipping to 10 hours in October and further diminishing to just 8 hours by November. Overall, September encapsulates a unique blend of lingering warmth and the gradual onset of seasonal change, making it a captivating moment within the yearly cycle.
As September arrives in Boston, UK, the wind begins to settle into a gentle rhythm, with an average speed of 3.9 m/s (approximately 9 mph). This marks a slight decline from the summer months, where the winds were more brisk, particularly in August at 4.3 m/s (10 mph). Compared to the earlier months of the year, September's winds hint at the transition toward autumn, following a trend of increasingly calming breezes from July's low point of 3.5 m/s (8 mph). This pattern signals a shift in the season, as residents and visitors prepare for the cooler, more blustery days ahead, particularly as October’s winds pick up again to 5.4 m/s (12 mph). Overall, September embodies a period of moderation, blending the tail end of summer’s warmth with the anticipation of autumn's arrival.
The weather in Boston changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September'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.
September and January present markedly different weather conditions. In September, temperatures span from a chilly 4°C (39°F) at night to a warm 28°C (83°F) during the day, accompanied by an average of 15°C (59°F). The month experiences significant rainfall, with approximately 60 mm (2.4 in) falling over about 10 days, and humidity levels are relatively high at 84%. In contrast, January is much colder, featuring a temperature range from -4°C (26°F) to a maximum of 15°C (59°F), with an average of only 5°C (41°F). Rainfall decreases to around 43 mm (1.7 in) spread over 8 days, and humidity increases slightly to 89%. For more detailed insights on January weather, check Boston weather in January.
In September, temperatures range from a cool minimum of 4°C (39°F) to a warm maximum of 28°C (83°F), with an average temperature of 15°C (59°F). The month experiences about 60 mm (2.4 in) of precipitation over approximately 10 days, with humidity levels sitting at a comfortable 84%. In contrast, February presents much colder conditions, featuring a minimum temperature of -6°C (22°F) and a maximum of 17°C (63°F), with an average of 6°C (43°F). Precipitation is slightly lower at 58 mm (2.3 in) across 11 days, and humidity rises to 87%. Overall, September offers a milder and drier climate compared to the chillier and slightly wetter February. For more specific details on February weather, you can check Boston weather in February.
When comparing the weather in September and March, we see distinct differences in temperature and overall climate. September boasts a more temperate range, with minimums around 4°C (39°F) and maximums reaching 28°C (83°F), resulting in an average of 15°C (59°F). In contrast, March starts cooler, with minimum temperatures plummeting to -5°C (24°F) and a moderate average of 7°C (45°F). Both months experience similar amounts of precipitation, with September slightly wetter at 60 mm (2.4 in) compared to March's 56 mm (2.2 in), though March sees rain on slightly more days, totaling 12 compared to September's 10. Humidity is comparably high in both months, at 84% for September and 86% for March, reflecting a damp chill in the air as winter transitions to spring. For a more detailed look, you can check out Boston weather in March.
When comparing the weather in September and April, notable differences emerge. September typically boasts milder temperatures, with a minimum of 4°C (39°F) and an average high of 28°C (83°F), while April's temperatures range from a chilly -1°C (31°F) to a maximum of 26°C (79°F). Additionally, September experiences more precipitation, averaging 60 mm (2.4 in) over 10 days, compared to April's 32 mm (1.3 in) over 8 days. Both months are relatively humid, with September at 84% and April slightly higher at 85%. For more details on April's weather patterns, you can check out Boston weather in April.
September and May exhibit notable similarities and differences in weather characteristics. In September, temperatures range from a minimum of 4°C (39°F) to a maximum of 28°C (83°F), with an average of 15°C (59°F). The month sees around 60 mm (2.4 in) of precipitation over approximately 10 days, with humidity levels at 84%. In contrast, May starts with slightly cooler temperatures, with a minimum of 1°C (35°F) and an average of 12°C (54°F), peaking at 27°C (80°F). It experiences a bit more precipitation at 65 mm (2.6 in) across about 12 days and a slightly lower humidity of 83%. For more detailed insights, check out Boston weather in May.
September and June weather exhibit notable differences, with September generally experiencing slightly lower temperatures and higher humidity. In September, temperatures range from a minimum of 4°C (39°F) to a maximum of 28°C (83°F), averaging around 15°C (59°F), while June sees a marginally warmer range with temperatures from 6°C (43°F) to 30°C (86°F), averaging 16°C (61°F). Additionally, while both months receive a similar amount of precipitation, September tends to have slightly less, accumulating around 60 mm (2.4 in) over about 10 days compared to June's 74 mm (2.9 in) over 11 days. Given these factors, June typically feels warmer and wetter than September. For more detailed information, check out Boston weather in June.
When comparing the weather in September to that of July, notable differences emerge. September experiences a cooler range of temperatures, with a minimum of 4°C (39°F) and a maximum of 28°C (83°F), while July boasts warmer conditions, with lows at 8°C (47°F) and highs reaching 33°C (91°F). Precipitation is slightly heavier in July, totaling 69 mm (2.7 in) over 11 days, compared to September’s 60 mm (2.4 in) over 10 days. Humidity levels are also slightly higher in September at 84%, compared to 79% in July. To explore more about July's weather, you can refer to this link: Boston weather in July.
In comparing the weather between September and August, we observe some notable differences. September features a wider temperature range with a minimum of 4°C (39°F) and a maximum of 28°C (83°F), resulting in a comfortable average of 15°C (59°F). In contrast, August tends to be warmer, with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 32°C (89°F), culminating in an average of 17°C (64°F). Precipitation is slightly higher in August at 80 mm (3.1 in) over 12 days, while September receives 60 mm (2.4 in) over 10 days. Humidity levels in September are also higher at 84%, compared to August's 78%. For more information, check out Boston weather in August.
September weather features a wider temperature range, with minimums around 4°C (39°F) and maximums reaching 28°C (83°F), resulting in an average of 15°C (59°F). The month experiences 60 mm (2.4 in) of precipitation over about 10 days, coupled with a humidity level of 84%. In contrast, October sees a slight drop in temperatures, with minimums of 2°C (36°F), averages of 12°C (53°F), and maximums around 24°C (76°F). Rainfall increases to 74 mm (2.9 in) spread over 13 days, while humidity rises slightly to 88%. For more detailed insights, you can visit Boston weather in October.
September weather is characterized by a wider temperature range, with minimums around 4°C (39°F) and maximums reaching up to 28°C (83°F), creating generally mild conditions with an average temperature of 15°C (59°F). In contrast, November sees temperatures drop significantly, with minimums plunging to -2°C (29°F) and average highs capped at 18°C (64°F), leading to a cooler overall climate, averaging just 8°C (46°F). Both months experience a similar number of rainy days, around 10, but November has slightly less precipitation at 54 mm (2.1 in) compared to September’s 60 mm (2.4 in). Additionally, November's humidity increases to 89%, making it feel even colder than the already brisk temperatures suggest. For more detailed insights on November conditions, you can check Boston weather in November.
In September, temperatures in Boston fluctuate from a mild minimum of 4°C (39°F) to a pleasant maximum of 28°C (83°F), with an average of 15°C (59°F). The month sees around 60 mm (2.4 in) of precipitation spread over 10 days, and humidity levels hover around 84%. In contrast, December brings a significant drop in temperature, with minimums dipping to -2°C (29°F) and an average of only 6°C (43°F). Precipitation increases to 72 mm (2.8 in) over 15 days, while humidity rises slightly to 88%. For more details on December weather, you can explore Boston weather in December.
As summer transitions into fall, September in Boston showcases a delightful mix of warmth and refreshing crispness. With temperatures averaging a pleasant 15°C (59°F), it’s a welcome change from the higher peaks of summer, yet still allows for enjoyable outdoor activities. The humility often reaches 84%, contributing to a subtle, comforting blanket of moisture in the air. However, don’t forget your umbrella; September sees about 10 days of rain, accumulating around 60 mm (2.4 in), reminding us that the city is brushing off the heat and preparing for the cooler months ahead. For a deeper dive into Boston's year-round climate, check out Boston Climate.