Last updated: March 17, 2025
In Plymouth, United Kingdom, September unveils a delightful transition from summer to autumn. With a maximum temperature peaking at 21°C (70°F) and an average of 15°C (60°F), the days remain mild and inviting. However, be prepared for the occasional shower, as the month brings about 73 mm (2.9 in) of rain over 12 wet days. The humidity hovers around a comfortable 79%, adding a touch of crispness to the air. This blend of warmth and moisture sets the perfect backdrop for exploring the city's stunning coastal scenery and vibrant culture.
As September graces Plymouth, the city begins to embrace the transition from summer to autumn, reflected in its temperatures. With minimums hovering around 10°C (50°F) and averages settling at a comfortable 15°C (60°F), the month invites a pleasant warmth, while the maximums peak at a delightful 21°C (70°F). This shift from the balmy heights of summer is subtle yet significant, marking the gradual decline in temperatures that will continue into the fall. Overall, September offers a harmonious blend of warmth and crispness, making it an inviting time for outdoor activities amidst the scenic backdrop of such a vibrant coastal city.
In September, Plymouth experiences an average precipitation of 73 mm (2.9 in) across 12 days, maintaining a trend of moderate rainfall typical for the month. This level of precipitation is slightly lower than the wetter autumn months that follow, such as October and December, which see notable spikes. Interestingly, September's rainfall correlates closely with the preceding months of August and July, reflecting a gradual transition into the autumn season. As the year progresses, these patterns suggest that while September retains summer's lingering moisture, the skies soon become darker and the rainy days more frequent as Plymouth braces for the heavier downpours that characterize the later months.
As summer gives way to autumn in Plymouth, September showcases a modest drop in humidity, settling at 79%. This reflects a gradual decrease from the sultry heights of July and August, which boasted humidity levels of 70% and 73%, respectively. The trend towards lower humidity is a gentle reminder that crisp fall days are on the horizon. While the air feels comparatively drier than the oppressive winter months—with January and February each reaching a high of 88%—September's humidity still carries traces of summer's lingering warmth. This transitional month acts as a bridge between the dry comfort of summer and the wetness that characterizes Plymouth's notorious autumn, where humidity returns to notable levels in October and beyond.
As September rolls into Plymouth, the UV Index stands at 6, placing it in the high exposure category with a burn time of just 25 minutes. This marks a slight decrease from August's UV Index of 7, but it still highlights the importance of sun safety as summer transitions into autumn. Throughout the year, Plymouth experiences a variation in UV levels, peaking in June with a very high index of 9. If you're planning outdoor activities this month, remember to protect your skin, as the sun can still be quite intense. For more detailed information, check out the Plymouth UV Index.
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September in Plymouth, United Kingdom, ushers in a beautiful transition from the vibrant summer months to the crispness of autumn. With 330 hours of sunshine, it stands out as a remarkably bright month, although it marks a decline from the sun-drenched days of July and August. This dip in sunshine hours may signal the onset of shorter days, yet September still offers a generous kiss of warmth and light, making it a delightful time for outdoor activities. Interestingly, as the year progresses, the trend reveals a gradual decline in sunshine hours, with winter months like January and December barely reaching 99 and 121 hours respectively, reminding us just how precious those late summer rays in September truly are.
While September in Plymouth, United Kingdom, brings the promise of autumn, it retains a moderate chance of sunny weather at 35%. This figure follows a fluctuating trend throughout the year, with a noticeable peak in April at 55%, showcasing the transition into spring. However, as summer fades, the likelihood of sun dips again, reflecting the changing seasons. Compared to the warmer months like July and August, which boast 40% and 32% chances respectively, September provides a more balanced climate. Although not the sunniest month, its 35% chance still invites hopeful souls to enjoy the lingering warmth before the cooler autumn days set in.
As the warmth of summer gradually recedes, Plymouth experiences a gentle decline in daylight duration during September, offering around 12 hours of light each day. This month marks a noticeable shift from the long, sun-soaked days of August, which boasted 14 hours, to the more muted light that heralds the approach of autumn. Ultimately, September serves as a bridge, allowing residents and visitors alike to savor the remaining golden hours before the daylight dwindles further in October, when only 10 hours remain. The transition is palpable, as Plymouth prepares for the cozy embrace of fall, where shorter days lead to crisper evenings and a vibrant shift in seasonal activities.
As September settles in Plymouth, the average wind speed gently drops to 5.1 m/s (11 mph), reflecting a transition from the summer breezes. This month marks a notable shift, presenting a decline from the summer wind patterns of July and August, where speeds hovered around 5.1 m/s to 5.3 m/s. Interestingly, this decrease is consistent with the overall trend of easing winds as autumn approaches, with October expected to bring a slight uptick to 6.5 m/s (15 mph). Overall, September’s winds serve as a whisper of change, inviting residents and visitors alike to embrace the cooler, crisper days ahead.
The weather in Plymouth 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 Plymouth and find detailed weather information for every month.
In comparing the weather of September and January, we see notable differences in temperature and humidity. September offers a mild temperature range, with averages around 15°C (60°F) and highs reaching 21°C (70°F), while January is much cooler, with an average of just 8°C (47°F) and maximum temperatures capped at 14°C (57°F). Both months experience similar levels of precipitation, with September recording 73 mm (2.9 in) and January slightly higher at 78 mm (3.1 in), and both months seeing about 12 days of rain. However, January is generally more humid, with humidity levels at 88% compared to September's 79%. For more specific details on January weather, you can check Plymouth weather in January.
September and February exhibit notably contrasting weather patterns. In September, temperatures range from a mild 10°C (50°F) to a comfortable 21°C (70°F), with an average of 15°C (60°F) and a humidity level of 79%. This month experiences 73 mm (2.9 in) of precipitation over about 12 days. In stark contrast, February brings colder temperatures, with a minimum of -1°C (31°F) and a maximum of only 13°C (55°F), averaging around 8°C (47°F). Additionally, February is wetter, with a total precipitation of 102 mm (4.0 in) spread across approximately 15 days, accompanied by higher humidity at 88%. For more specific insights, you can check Plymouth weather in February.
In September, the weather is generally milder, with average temperatures ranging from 10°C (50°F) to a pleasant 21°C (70°F), and the humidity sits at 79%. The month sees about 73 mm (2.9 in) of precipitation over approximately 12 days. In contrast, March experiences cooler temperatures, with averages between -2°C (29°F) and 14°C (57°F), and higher humidity at 86%. March also tends to be wetter, receiving around 93 mm (3.7 in) of rainfall across about 15 days. For more detailed information, check out Plymouth weather in March.
In comparing the weather of September and April, notable differences emerge. September typically enjoys warmer temperatures, with averages around 15°C (60°F) and highs reaching up to 21°C (70°F), while April sees cooler averages of 10°C (50°F) and maximums of 17°C (62°F). Precipitation is also more frequent in September, with about 73 mm (2.9 in) over 12 days compared to April's 48 mm (1.9 in) over 8 days. Humidity levels are slightly higher in April, at 84%, compared to September's 79%. For more detailed information, check out Plymouth weather in April.
In comparing the weather of September and May, September tends to be slightly warmer, with average temperatures ranging from 10°C (50°F) to a maximum of 21°C (70°F), compared to May's range of 6°C (43°F) to 19°C (67°F). Both months experience similar levels of precipitation, with September receiving 73 mm (2.9 in) over 12 days and May accumulating 75 mm (2.9 in) over 11 days. Humidity is fairly consistent, with September at 79% and May slightly higher at 80%. For more detailed information, you can check Plymouth weather in May.
In comparing the weather of September and June, both months exhibit similar temperature ranges, with September’s highs reaching 21°C (70°F) and June slightly warmer at 22°C (72°F). The average temperatures in both months hover around 15°C (59°F-60°F), and the minimum temperatures are identical at 10°C (50°F). Precipitation is fairly comparable as well, with September receiving 73 mm (2.9 in) and June a little higher at 77 mm (3.0 in), both spread over 12 days. Humidity levels are also similar, with September at 79% and June slightly higher at 80%. For more detailed information, you can check out this link: Plymouth weather in June.
In comparing the weather between September and July, we notice a slight drop in temperatures as September features minimums of 10°C (50°F) and maximums of 21°C (70°F), compared to July’s minimum of 12°C (53°F) and maximum of 24°C (75°F). The average temperature in September is 15°C (60°F) while July averages at 17°C (63°F), indicating that July is typically warmer. Both months see similar levels of precipitation, with September recording 73 mm (2.9 in) over 12 days and July at 72 mm (2.8 in) across 10 days, although September experiences slightly more rainy days. Additionally, September has a higher humidity level at 79%, compared to July’s 70%, making the later summer month more comfortable in terms of moisture in the air. For more detailed insights into July's weather, you can visit Plymouth weather in July.
In comparing the weather between September and August, September experiences a slight dip in temperatures, with minimums of 10°C (50°F) and maximums reaching 21°C (70°F), while August averages slightly warmer temperatures with a minimum of 13°C (55°F) and a maximum of 23°C (73°F). Precipitation levels are quite similar, with September receiving 73 mm (2.9 in) over 12 days compared to August's 78 mm (3.1 in) over the same number of days. Additionally, September's humidity is higher at 79%, compared to August's 73%, contributing to a more humid feel as the month progresses. For a detailed look at August weather, check out Plymouth weather in August.
September generally showcases milder temperatures, with minimums around 10°C (50°F) and maximums reaching 21°C (70°F), while October sees a slight drop, with minimums at 5°C (41°F) and maximums capping at 19°C (66°F). The average temperature in September is about 15°C (60°F), compared to October's cooler average of 13°C (56°F). Additionally, October tends to be wetter, experiencing 138 mm (5.4 in) of precipitation over 16 days, while September records 73 mm (2.9 in) over 12 days. Humidity also increases in October, rising to 89% from September's 79%. For more detailed insights, you can check out the Plymouth weather in October.
In September, the weather tends to be milder, with average temperatures ranging from a minimum of 10°C (50°F) to a maximum of 21°C (70°F) and relatively lower precipitation at 73 mm (2.9 in) over about 12 days. The humidity level rests at around 79%, creating a comfortable atmosphere for outdoor activities. In contrast, November brings cooler temperatures, with averages dropping to a minimum of 4°C (40°F) and a maximum of 16°C (60°F). The month experiences increased rainfall, totaling 115 mm (4.5 in) spread across about 17 days, contributing to a higher humidity level of 90%. This shift in weather signifies a transition from early autumn warmth to the chillier, wetter conditions typical of late fall. For more detailed information, you can check Plymouth weather in November.
September and December present contrasting weather patterns. In September, temperatures range from a minimum of 10°C (50°F) to a maximum of 21°C (70°F), with an average of 15°C (60°F). The month experiences 73 mm (2.9 in) of precipitation over about 12 days, coupled with a humidity level of 79%. On the other hand, December brings cooler conditions, with temperatures dropping to a minimum of 4°C (39°F) and peaking at 14°C (57°F), averaging 10°C (49°F). This month sees increased rainfall, totaling 141 mm (5.6 in) spread across 20 days, along with a higher humidity of 89%. For more details on December weather, visit Plymouth weather in December.
As summer transitions to autumn, September in Plymouth brings a delightful shift in weather. With temperatures generally cooler than the peak summer months, visitors can expect a refreshing average of around 15°C (60°F), providing a comfortable atmosphere for outdoor activities. However, with nearly half the month experiencing rainy days, the air carries a touch of humidity that can make it feel more vibrant. This blend of mild temperatures and occasional showers distinguishes September from the warmer, drier months of July and August. For those looking to understand Plymouth's unique atmospheric patterns throughout the year, be sure to explore more details in the comprehensive Plymouth Climate guide.