September Weather in Lewes, United Kingdom

Last updated: March 17, 2025

September weather in Lewes, United Kingdom offers a delightful mix of mild temperatures and refreshing rainfall. The maximum temperature reaches a pleasant 21°C (71°F), while the average settles around 16°C (62°F). Expect cooler nights, with temperatures dipping to a minimum of 10°C (50°F). With 67 mm (2.6 in) of precipitation over 11 days, the humidity hangs at a comfortable 80%, creating a cozy atmosphere perfect for enjoying the lush English countryside. Whether you're exploring the historic town or strolling through its scenic landscapes, September in Lewes promises a charming blend of weather elements.

September Temperature in Lewes

As September rolls into Lewes, UK, a noticeable shift heralds the arrival of autumn. Temperatures begin to cool, with nightly lows averaging around 10°C (50°F), while daytime warmth offers a comfortable 16°C (62°F) on average, peaking at 21°C (71°F). This month captures a beautiful transition, blending the lingering warmth of summer with the crispness of fall. Outdoor enthusiasts can savor the mild climate, perfect for exploring the charming streets of Lewes or enjoying the scenic countryside. As the leaves start to turn, September is a gentle reminder of nature's cycle, inviting residents and visitors alike to relish the beauty of change.

September Weather in Lewes: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Lewes, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec454546485359636461575148
Data source: Temperature data for Lewes generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Lewes

September in Lewes sees a moderate level of rainfall, with 67 mm (2.6 in) recorded over 11 days. This marks a slight decrease from the preceding summer months, where August delivered 74 mm (2.9 in) across 12 days. As the transition into autumn begins, September's precipitation is characterized by more frequent, yet not overwhelming, showers—a pattern that hints at the impending wetter months ahead. The consistent rainfall during this time is essential for replenishing local water sources, but it also serves as a reminder that heavier downpours lay just around the corner, with October likely bringing a significant uptick to 133 mm (5.2 in).

September Precipitation Trends in Lewes

The chart displays monthly precipitation patterns in Lewes, with values for each month alongside September's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec798369304865517467133119149
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Lewes

As September settles in Lewes, United Kingdom, the humidity begins to rise slightly, reaching 80% after the lower summer levels, which peaked at 73% in August. This modest increase marks the transition into autumn, where the humidity levels generally trend upward again, creeping closer to the winter averages of 89% in October and 92% by November and December. Notably, this seasonal shift reflects a pattern where the air tends to become more moist as the year progresses, reminding locals of the maritime influences that characterize the region’s climate. The early onset of autumn in September plays a crucial role in setting the stage for the dampness that follows, making it a month of subtle yet significant change in humidity.

September Average Humidity in Lewes

This chart illustrates the average monthly humidity levels in Lewes, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec91%89%86%85%82%81%76%73%80%89%92%92%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Lewes

As September arrives in Lewes, United Kingdom, the UV Index lowers slightly to 6, which falls under the high exposure category. This indicates a need for mindful sun protection, as burn time hovers around 25 minutes for unprotected skin. Following the peak summer months, where UV Index values reached a high of 8, it's clear that while the intensity of sunlight diminishes, awareness remains crucial. As the autumn months beckon, residents and visitors should still take care to safeguard their skin during this transition. For more detailed information, check out Lewes UV Index.

Maximum UV Index Levels in Lewes for September

The chart shows the monthly maximum UV Index (UVI) for Lewes in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec224678876421
Data source: Lewes September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Lewes

As summer gracefully transitions into autumn, September in Lewes offers a delightful mix of warmth and sunlight, boasting 325 hours of sunshine. This marks a gentle decline from the peak of summer, where July dazzles with 424 hours. Yet, September retains a charm, providing ample light for enjoying the last days of outdoor festivities, a stark contrast to the dimmer months ahead like November and December, which only offer 155 and 119 hours, respectively. The month thus captures a sweet farewell to summer's abundance while hinting at the cozy, reflective days of autumn to come. September's dwindling sunshine, coupled with its vibrant atmosphere, sets the perfect stage for leisurely strolls along the South Downs and picturesque evenings by the sea.

Monthly Sunshine Duration in Lewes: September Highlighted

The September sunshine duration represents the total number of hours Lewes experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec99h152h229h348h415h412h424h388h325h256h155h119h
Data source: Lewes September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Lewes During September

September in Lewes, United Kingdom, offers a moderate chance of sunny weather, with the likelihood of sunshine hovering around 38%. This seasonal transition shows a slight dip from the summer months, where July and August enjoy peaks of 42% and 39% respectively. As autumn approaches, the playful warmth of late summer gives way to the more unpredictable skies of early autumn, contributing to a noteworthy decrease in sunny days compared to the vibrant spring period. While September may not boast the highest rates of sun, it still holds the potential for pleasantly bright days, ideal for enjoying the beautiful landscapes of Lewes before the chill of October sets in.

Percentage of Sunny Days in September in Lewes

The chart illustrates the percentage of sunny days in Lewes throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Lewes experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec21%25%42%59%43%32%42%39%38%31%36%21%
Data source: Lewes September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Lewes in September

As September unfolds in Lewes, United Kingdom, daylight begins its gentle retreat, offering about 12 hours of sunlight each day. This month marks a transition from the summer's peak brightness, with June basking in 16 hours of light, to the cozy embrace of autumn. The gradual decrease in daylight is consistent with the seasonal shift, as September's hours reveal a drop from the vibrant 14 hours of August, signaling the approach of shorter days ahead. This decline continues into October, where daylight narrows to 10 hours, emphasizing the rhythmic ebb and flow of light that characterizes the changing seasons in this picturesque coastal town.

Average Daylight Hours in Lewes for September

The chart illustrates the variation in daylight duration in Lewes throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 30m10h 1m11h 55m13h 51m15h 32m16h 24m15h 56m14h 26m12h 34m10h 39m8h 56m8h 1m
Data source: Lewes daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Lewes

As the summer winds down in September, Lewes experiences a gentle breeze averaging 5.6 m/s (13 mph). This marks a gradual decline from the peak wind speeds of the earlier months, with August bringing slightly stronger gusts at 6.3 m/s (14 mph). September's winds hint at the transition into autumn, where the breeze becomes more subdued compared to the robust gusts of spring and winter, which feature average speeds of 7.9 m/s (18 mph) in both January and October. This subtle drop in wind speed aligns with the overall trend of diminishing warmth, hinting at the cozy, cooler days ahead.

Average September Wind Speed in Lewes

The chart displays monthly wind speed patterns in Lewes, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec7.98.16.95.97.14.55.46.35.6 m/s7.96.88.0
Data source: Lewes September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Lewes Compares to Other Months

The weather in Lewes 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 Lewes and find detailed weather information for every month.

September and January showcase distinct weather patterns, with September typically presenting warmer temperatures and a milder climate. In September, the average temperature hovers around 16°C (62°F), with highs reaching 21°C (71°F) and lows at 10°C (50°F). This month also experiences 67 mm of precipitation over 11 days, coupled with a relatively comfortable humidity of 80%. In contrast, January is much cooler; the average temperature drops to 7°C (45°F), with highs of 12°C (55°F) and lows plummeting to 1°C (34°F). January sees slightly higher precipitation at 79 mm over 12 days, along with increased humidity at 91%. For more details on January weather, visit Lewes weather in January.

September and February present contrasting weather patterns, with September generally being milder and more temperate. In September, temperatures range from a minimum of 10°C (50°F) to a maximum of 21°C (71°F), along with an average temperature of 16°C (62°F). There is some precipitation, totaling 67 mm (2.6 in) across about 11 days, and humidity sits at a comfortable 80%.

In contrast, February brings chillier conditions, with temperatures dipping as low as -1°C (30°F) and reaching a maximum of 12°C (54°F), resulting in a lower average temperature of just 7°C (45°F). The month is also wetter, with precipitation at 83 mm (3.3 in) over 14 days, and higher humidity levels at 89%. For those interested in more detailed weather patterns, check out Lewes weather in February.

September and March present contrasting weather patterns. In September, temperatures range from a minimum of 10°C (50°F) to a maximum of 21°C (71°F), with an average of 16°C (62°F), accompanied by 67 mm (2.6 in) of precipitation over about 11 days, and humidity sitting at a comfortable 80%. In stark contrast, March experiences chillier conditions, with temperatures dipping as low as -2°C (30°F) and peaking at just 13°C (55°F), averaging around 8°C (47°F). Despite a similar level of precipitation at 69 mm (2.7 in), it spans 14 days and boasts higher humidity at 86%. For a more detailed look, you can check the Lewes weather in March.

September and April present distinct contrasts in weather. In September, temperatures typically range from a minimum of 10°C (50°F) to a maximum of 21°C (71°F), leading to a more moderate average of 16°C (62°F). The month experiences about 67 mm (2.6 in) of precipitation over 11 days, with humidity around 80%. In contrast, April is noticeably cooler, with temperatures ranging from a minimum of 2°C (36°F) to a maximum of 15°C (60°F) and an average of just 9°C (49°F). With precipitation totaling 30 mm (1.2 in) over 6 days, humidity is slightly higher at 85%. Overall, September offers milder and sunnier conditions compared to the chillier and wetter April. For more detailed insights on April's weather, you can check Lewes weather in April.

When comparing the weather in September and May, September tends to be slightly warmer on average, with temperatures ranging from a minimum of 10°C (50°F) to a maximum of 21°C (71°F), compared to May’s range of 5°C (42°F) to 19°C (66°F). Moreover, September experiences more precipitation at 67 mm (2.6 in) over 11 days, whereas May sees a total of 48 mm (1.9 in) over just 9 days. Humidity levels remain relatively high in both months, with September at 80% and May slightly higher at 82%. For a detailed look at May's weather, you can visit Lewes weather in May.

In comparing the weather of September and June, both months exhibit similar maximum temperatures, reaching around 21°C (71°F). However, September tends to be slightly warmer on average, with temperatures hitting an average of 16°C (62°F) compared to June's average of 15°C (59°F). Precipitation levels are also comparable, with September receiving 67 mm (2.6 in) over 11 days, while June has a similar total of 65 mm (2.6 in) across 8 days. The humidity levels are quite high in both months, with September at 80% and June at 81%. For a detailed look at June's weather specifics, you can check Lewes weather in June.

In comparing July and September weather, July tends to be slightly warmer, with average temperatures ranging from a minimum of 13°C (56°F) to a maximum of 23°C (74°F), while September shows a cooler range of 10°C (50°F) to 21°C (71°F). Additionally, July experiences less precipitation, totaling 51 mm (2.0 in) over about 9 days, compared to September's 67 mm (2.6 in) over 11 days. Humidity levels are also a bit lower in July at 76%, compared to 80% in September. For more specific information, you can check Lewes weather in July.

In comparing the weather of September and August, September tends to be cooler and slightly wetter than August. The average temperature in September is around 16°C (62°F) with maximums reaching up to 21°C (71°F), whereas August experiences warmer conditions with averages of 18°C (64°F) and highs of 25°C (77°F). Precipitation is relatively close between the two months, with September receiving about 67 mm (2.6 in) over 11 days compared to August's 74 mm (2.9 in) across 12 days. Additionally, September is more humid at 80% compared to August's 73%. For a more detailed look at August weather in Lewes, you can visit Lewes weather in August.

In comparing the weather between September and October, September tends to be milder with average temperatures around 16°C (62°F) and a maximum of 21°C (71°F). It experiences less precipitation, totaling 67 mm (2.6 in) over 11 days, alongside a humidity level of 80%. In contrast, October sees a drop in average temperatures to 14°C (58°F) and lower maximums at 20°C (68°F). However, it is significantly wetter, receiving 133 mm (5.2 in) of rain over 16 days, with humidity rising to 89%. For more detailed information, you can check this link: Lewes weather in October.

September generally offers milder weather compared to November, with average temperatures ranging from a minimum of 10°C (50°F) to a maximum of 21°C (71°F). In contrast, November experiences cooler conditions, with average temperatures dipping to a minimum of 3°C (37°F) and a maximum of 16°C (61°F). Additionally, November sees significantly more precipitation, totaling 119 mm (4.7 in) over 16 days, compared to September's 67 mm (2.6 in) across 11 days. The humidity also rises in November to 92%, making it feel damp, while September maintains a lower humidity level of 80%. For more details on November weather, you can check Lewes weather in November.

In September, the weather is relatively mild, with average temperatures ranging from a minimum of 10°C (50°F) to a maximum of 21°C (71°F), accompanied by an average humidity of 80%. During this month, there is a moderate amount of precipitation, totaling 67 mm (2.6 in) over about 11 days. In contrast, December brings much colder temperatures, with an average low of 2°C (35°F) and a high of only 13°C (56°F). The precipitation also increases significantly to 149 mm (5.9 in) over approximately 18 days, alongside higher humidity levels at 92%. For more details on December weather, check out Lewes weather in December.

Compare Lewes's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Lewes

As summer gives way to autumn, September in Lewes presents a charming transition characterized by cooler temperatures and an uptick in rainfall. Unlike the balmy conditions of the peak summer months, the weather shifts toward an average temperature of around 16°C, making it more refreshing for outdoor activities. Humidity remains relatively high, contributing to an interesting mix of crisp and damp days, with about 11 days of precipitation scattered throughout the month. This makes September a unique time to experience the evolving landscape of Lewes, inviting visitors to enjoy the vibrant fall scenery. For detailed insights into the weather patterns, check out Lewes Climate.