Last updated: March 17, 2025
Bristol in September offers a delightful blend of summer warmth and early autumn crispness. With maximum temperatures reaching 29°C (84°F), the city experiences an average temperature of 15°C (59°F), making it a comfortable time to explore. However, temperatures can dip as low as 2°C (36°F), so layering is recommended for cooler evenings. While residents and visitors can expect approximately 55 mm (2.2 in) of rain over 9 days, the humidity levels hover at a high 79%, adding to the lush, vibrant atmosphere of this picturesque city. September in Bristol is perfect for enjoying both sunny days and refreshing, rain-kissed adventures.
In September, Bristol experiences a gentle transition from summer to autumn, reflected in its temperatures. With minimums settling around 2°C (36°F) and average highs reaching an inviting 29°C (84°F), residents and visitors alike can enjoy pleasant days that still carry a whisper of summer warmth. The average temperature of 15°C (59°F) provides a comfortable backdrop for outdoor activities, making it an ideal time for exploring the city's parks and waterfront. As summer's heat begins to fade, September hints at the changing season without the sharp chill of autumn yet to come, creating a unique balance that invites everyone to savor the last stretches of warm weather.
In September, Bristol experiences a moderate level of rainfall, with an average precipitation of 55 mm (2.2 in) over approximately 9 days. This marks a slight decrease from the preceding month's wetter conditions in August, which recorded 78 mm (3.1 in). As summer transitions into autumn, September's rainfall signals the onset of cooler, wetter weather patterns typical of the season. Compared to the year's earlier months, it also sits on the lower end of the spectrum, particularly against the backdrop of October, which often sees a significant uptick with 101 mm (4.0 in) expected as the region braces for more sustained rainfall. Overall, September's precipitation serves as a gentle precursor to the more pronounced weather changes that lie ahead.
In September, Bristol experiences a relative drop in humidity, with levels averaging 79%. This transition marks a shift from the summer months, where humidity peaked at 73% in August, towards the wetter autumn conditions that follow. The trend reveals a gradual decline from the typically high humidity levels of winter, which can reach up to 90% in November. As September unfolds, the air becomes crisper, hinting at the impending seasonal change while still retaining a touch of summer's lingering warmth. Overall, this month serves as a bridge—balancing the residual warmth of summer with the anticipation of autumn's moisture-rich atmosphere.
As September unfolds in Bristol, the UV Index hovers at a moderate to high level of 6, indicating that while protections are necessary, the risk is not at its peak. This month typically sees continued sunlight from the summer, fostering the last warm days before autumn sets in. With a burn time of 25 minutes, it’s essential for residents and visitors alike to be mindful of sun exposure, especially during midday hours. Compared to the very high indices of July and June, September offers a slight reprieve, yet precautions should remain a priority as the sun’s rays can still pose a risk on those clear days. For more detailed information on UV levels throughout the year, check out the Bristol UV Index.
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As the summer fades in Bristol, September brings a delightful blend of sunshine, with 284 hours of golden rays gracing the city. This month captures the tail end of the sunny season, showcasing a subtle decline from the peak summer months, with July basking in an impressive 395 hours of sunlight. September's brightness lingers longer than the cooler autumn months to come, with October witnessing a drop to 231 hours. The trend reflects a gradual transition, where the warmth of late summer meets the crispness of fall, making September a perfect time to enjoy outdoor activities before the chill sets in.
September in Bristol sees a 26% chance of sunny weather, mirroring the somewhat inconsistent patterns of the previous summer months. As we transition from the warmth of August, which also holds a 26% likelihood for sunshine, September offers a balanced mix of pleasant days and occasional overcast skies. The data reveals a notable uplift in sunny conditions during the spring months—April peaking at 52%—but as autumn approaches, the likelihood dips back to levels more typical of the cooler months. While Bristol's September weather may not guarantee a sun-soaked experience, there’s still a decent chance to enjoy the lingering warmth of the summer sun, so keep your sunglasses handy!
As September rolls into Bristol, daylight begins to gracefully wane after the sun-drenched heights of summer. With approximately 12 hours of daylight, this month serves as a gentle transition from the vibrant 16-hour days of June and July to the shorter days of autumn. The steady decline from August's 14 hours marks a notable shift, ushering in cooler breezes and the early hints of changing leaves. As we shift into October, Bristol’s daylight will further decrease to 10 hours, signaling the gradual descent into winter's embrace. This rhythmic ebb and flow of daylight reflects the natural beauty of seasonal change, encouraging residents to cherish the lingering sunlight while it lasts.
As September arrives in Bristol, the wind begins to mellow, with average speeds dropping to 3.3 m/s (7 mph). This marks a continuation of the subtle decline in wind intensity observed during the summer months. Unlike the energetic gusts of February, which peaks at 5.1 m/s (12 mph), September’s breezes feel gentle and reminiscent of the more placid conditions seen in late spring. The transition from summer's calm winds to the slightly brisker autumn gales signifies a seasonal shift, hinting at the upcoming increased wind speeds in October at 4.2 m/s (10 mph). Thus, September captures that serene, balmy essence before the winds begin to pick up, offering a tranquil period in Bristol's annual climatic rhythm.
The weather in Bristol 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 Bristol and find detailed weather information for every month.
September and January present contrasting weather conditions. In September, temperatures range from a mild 2°C (36°F) to a warm 29°C (84°F), with an average of 15°C (59°F). The month sees about 55 mm (2.2 in) of precipitation over approximately nine days, coupled with a humidity level of 79%. In contrast, January experiences colder temperatures, with a minimum of -4°C (25°F) and a maximum of 14°C (58°F), leading to an average of 5°C (42°F). Despite having slightly more precipitation at 56 mm (2.2 in) over ten days, January is characterized by higher humidity at 88%. For more specific information about January weather, check out Bristol weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a mild 2°C (36°F) at night to a warm 29°C (84°F) during the day, with an average of 15°C (59°F). During this month, precipitation is relatively low at 55 mm (2.2 in) over 9 days, and humidity settles at 79%. In stark contrast, February experiences colder temperatures, with nighttime lows dipping to -5°C (23°F) and daytime highs reaching a maximum of 18°C (64°F), averaging just 6°C (44°F). This month also sees a rise in precipitation to 67 mm (2.6 in) spread across 13 days, and humidity increases further to 88%. For more detailed insights, visit Bristol weather in February.
When comparing the weather between September and March, we observe distinct differences in temperature and precipitation patterns. September enjoys a comfortable range, with temperatures varying from a chilly 2°C (36°F) to a warm 29°C (84°F) and an average of 15°C (59°F). In contrast, March experiences cooler conditions, with temperatures ranging from a low of -6°C (22°F) to a high of 21°C (71°F), averaging around 7°C (46°F).
Precipitation also varies, with September receiving 55 mm (2.2 in) over 9 days, while March sees a higher total of 74 mm (2.9 in) spread across 14 days. The humidity levels in March are slightly higher at 86%, compared to September's 79%, contributing to a different overall feel. For a more detailed look at March weather, check Bristol weather in March.
September typically experiences warmer temperatures compared to April, with averages ranging from 15°C (59°F) and highs reaching up to 29°C (84°F), while April’s temperatures range from a low of -3°C (27°F) to an average of 9°C (49°F), peaking at 23°C (74°F). Both months see similar levels of precipitation, with September recording 55 mm (2.2 in) over 9 days and April slightly lower at 50 mm (2.0 in) over 8 days. Humidity levels are fairly comparable, with September at 79% and April slightly higher at 84%. For a more detailed look at the weather patterns, you can visit Bristol weather in April.
September and May offer distinct weather characteristics, showcasing the transition from summer to autumn. In September, temperatures range from a minimum of 2°C (36°F) to a maximum of 29°C (84°F), with an average of 15°C (59°F). Conversely, May tends to be cooler with temperatures varying from 0°C (33°F) to 26°C (79°F) and an average of 12°C (55°F). Both months experience considerable precipitation, with September receiving 55 mm (2.2 in) over 9 days and May slightly wetter at 73 mm (2.9 in) over 11 days. Humidity levels remain fairly consistent, hovering around 79% in September and 80% in May. For a more detailed look at May’s weather, you can explore Bristol weather in May.
In comparing the weather patterns of September and June, we observe that September experiences a wider temperature range, with a minimum of 2°C (36°F) and a maximum of 29°C (84°F), resulting in an average temperature of 15°C (59°F). In contrast, June typically has a milder temperature profile, with minimums reaching 6°C (44°F), maximums up to 31°C (88°F), and an average of 16°C (61°F). While September receives about 55 mm (2.2 inches) of precipitation over 9 days, June sees slightly more rain, totaling 72 mm (2.8 inches) over 12 days. Humidity levels remain similar, with September at 79% and June slightly higher at 80%. For more detailed insights on June weather, check out Bristol weather in June.
In comparing the weather between September and July, we find notable differences in temperature and precipitation patterns. September experiences a wider temperature range, with minimums dipping to 2°C (36°F) and maximums reaching up to 29°C (84°F), resulting in an average temperature of 15°C (59°F). In contrast, July is warmer, with temperatures ranging from a minimum of 7°C (46°F) to a maximum of 30°C (87°F) and an average of 18°C (64°F).
Precipitation in September is slightly lower at 55 mm (2.2 in) over about 9 days, compared to July’s 68 mm (2.7 in) spread across 11 days. Additionally, September has a higher humidity level at 79%, while July maintains a more comfortable 70% humidity. For a more detailed look at July's climate, you can check Bristol weather in July.
In comparison to August, September experiences cooler temperatures, with a minimum of 2°C (36°F) and an average of 15°C (59°F), while August has a higher minimum of 8°C (46°F) and an average of 17°C (63°F). The maximum temperatures in September peak at 29°C (84°F), which is slightly lower than August's maximum of 32°C (90°F). Additionally, September has increased precipitation, totaling 55 mm (2.2 in) over 9 days, compared to August's 78 mm (3.1 in) over 12 days. Interestingly, September also has a higher humidity level at 79%, compared to August's 73%. For more details on August weather, check out Bristol weather in August.
September typically experiences warmer temperatures with a minimum of 2°C (36°F) and an average of 15°C (59°F), peaking at 29°C (84°F). However, it also sees some rainfall, with about 55 mm (2.2 in) of precipitation over 9 days and a humidity level of 79%. In contrast, October ushers in cooler conditions, with minimum temperatures dropping to -1°C (31°F) and an average of 12°C (53°F), while the maximum temperature is 23°C (73°F). Rainfall increases significantly, totaling 101 mm (4.0 in) over 14 days, and humidity rises to 89%. For more details, you can check Bristol weather in October.
September and November reflect a notable transition in weather patterns. In September, temperatures range from a chilly 2°C (36°F) at night to a warm 29°C (84°F) during the day, averaging around 15°C (59°F). The month typically experiences about 55 mm (2.2 in) of precipitation over 9 days, with a humidity level of 79%. In contrast, November sees a drop in temperatures, with minimums dipping to -2°C (28°F) and daytime highs reaching a maximum of 16°C (62°F), averaging only 8°C (47°F). Precipitation increases to 66 mm (2.6 in) over 13 days, accompanied by higher humidity at 90%. This shift showcases a significant cooling trend and more persistent wet conditions as autumn deepens. For more detailed insights, you can check Bristol weather in November.
September and December present stark contrasts in weather. September enjoys milder temperatures, ranging from a minimum of 2°C (36°F) to a maximum of 29°C (84°F), with an average of 15°C (59°F). This month experiences relatively moderate precipitation, totaling 55 mm (2.2 in) over about 9 days, and humidity levels are a comfortable 79%. In contrast, December brings colder conditions, with temperatures dropping to a minimum of -5°C (24°F) and peaking at 14°C (58°F), averaging around 7°C (44°F). The month is significantly wetter, with 90 mm (3.5 in) of precipitation spread across about 15 days, and humidity rises to 89%. For a more detailed look at the weather during this colder month, check out Bristol weather in December.
As September unfolds in Bristol, the weather offers a captivating blend of warmth and crispness, setting it apart from the balmy summer months. With maximum temperatures touching 29°C and an average of 15°C, it's a delightful time to enjoy the outdoors before the chill of autumn sets in. However, the 79% humidity and an increase in precipitation—with rain affecting nearly a third of the days—remind us that summer is giving way to fall. This transition creates a unique atmosphere in the city, filled with rich colors and a hint of coolness. If you're keen to learn more about what to expect throughout the year, check out the Bristol Climate page for detailed insights.