September Weather in Saint Sampson, Guernsey

Last updated: August 21, 2025

In September, Saint Sampson, Guernsey experiences a delightful transition into autumn, with maximum temperatures reaching 21°C (71°F) and an average of 17°C (62°F). The weather is generally mild, with minimum temperatures dipping to 12°C (54°F). A total of 63 mm (2.5 in) of rainfall occurs over 9 days, contributing to the lush greenery of the island. With humidity levels around 76%, residents and visitors can enjoy the crisp, invigorating air while savoring the beauty of the early fall season.

September Temperature in Saint Sampson

As September rolls into Saint Sampson, Guernsey, the temperatures begin to hint at the arrival of autumn. With minimums averaging 12°C (54°F) and a pleasant maximum of 21°C (71°F), the month presents a comfortable transition from the summer warmth. The average temperature of 17°C (62°F) ensures that outdoor activities remain enjoyable, while cooler evenings invite cozy gatherings. Compared to August, where the warmth peaks at 22°C (72°F), September’s milder climate marks a gentle shift, fostering a serene atmosphere amid the island's stunning scenery. This perfect blend of warmth and coolness invites both locals and visitors to savor the charming beauty of early fall in Guernsey.

September Weather in Saint Sampson: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Saint Sampson, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Saint Sampson, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec484848505458616362595451
Data source: Temperature data for Saint Sampson 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 Saint Sampson

In September, Saint Sampson experiences a notable shift in weather patterns, marked by 63 mm (or 2.5 inches) of precipitation over 9 days. This amount reflects a moderate increase compared to the summer months, suggesting that the region starts to embrace the wetter autumn conditions. As the year progresses, precipitation levels rise significantly, with October showing a sharp jump to 144 mm (5.7 in), hinting at the transition to more frequent rainfall. Interestingly, September's rainfall marks a departure from the typically drier summer, as it surpasses the totals of July and August, indicating the gradual approaching of the wet season that characterizes the latter part of the year in Guernsey.

September Precipitation Trends in Saint Sampson

The chart displays monthly precipitation patterns in Saint Sampson, 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. In Saint Sampson, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec948673345559375063144126163
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Saint Sampson

As summer fades into autumn, September brings a notable shift in humidity levels in Saint Sampson, Guernsey. After the warmest months, which saw humidity dip to a comfortable 63% in July and rise to 71% in August, September experiences a gentle rebound with humidity at 76%. This marks a transition towards the year’s wetter months, where humidity climbs back to 89% by October and reaches a peak of 90% in both November and December. The gradual increase from late summer sets the stage for the chilly, damp conditions typical of the island's winter, highlighting a clear trend of rising humidity as the year progresses towards its end.

September Average Humidity in Saint Sampson

This chart illustrates the average monthly humidity levels in Saint Sampson, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Saint Sampson is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec89%88%85%84%81%77%63%71%76%89%90%90%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Saint Sampson

In September, Saint Sampson experiences a UV Index of 6, indicating a high level of UV exposure that requires attentiveness to sun safety. Following the peak summer months of June and July, where the index reached very high levels of 9 and 8 respectively, September marks a slight decrease, yet you still need to be cautious. With a burn time of 25 minutes, it’s important to apply sunscreen and seek shade during midday hours. This trend highlights the lingering intensity of late summer sun, a reminder that UV protection remains vital as the season transitions. For more detailed information, visit Saint Sampson UV Index.

Maximum UV Index Levels in Saint Sampson for September

The chart shows the monthly maximum UV Index (UVI) for Saint Sampson 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. In September, the maximum UV index in Saint Sampson typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec234679876421
Data source: Saint Sampson 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 Saint Sampson

September in Saint Sampson, Guernsey, shines with a beautiful 338 hours of sunshine, offering a delightful transition from the summer glow. As the year progresses, we see a consistent upward trend, peaking in July with 436 hours, before gracefully tapering off in the fall months. This seasonal ebb and flow highlights the area's vibrant summer, with June and July basking in nearly continuous sunshine. Although September marks a decrease from the height of summer, it still provides ample warmth and light, creating an inviting backdrop for late-season outdoor activities amidst the lush scenery. As the days shorten into October with only 270 hours, September serves as a cherished reminder of the lingering summer days, perfect for enjoying the last sun-soaked moments before the cooler months arrive.

Monthly Sunshine Duration in Saint Sampson: September Highlighted

The September sunshine duration represents the total number of hours Saint Sampson 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.
JanFebMarAprMayJunJulAugSepOctNovDec107h163h238h359h414h416h436h396h338h270h181h130h
Data source: Saint Sampson September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Saint Sampson During September

As September arrives in Saint Sampson, Guernsey, residents and visitors can expect a 43% chance of sunny weather, marking a small uptick from the summer months. This slight increase in sunlight follows a pattern where by the end of summer, the likelihood of sunny days tends to wane, with July and August having a noteworthy 49% and 42% chance respectively. Interestingly, September holds its own, remaining more favorable than many other months like October and November. Overall, while the probability of sunny weather in September may not be as high as the peak spring months, it still offers a pleasant transition into autumn for those enjoying the coastal charm of Guernsey.

Percentage of Sunny Days in September in Saint Sampson

The chart illustrates the percentage of sunny days in Saint Sampson 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 Saint Sampson experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec21%28%38%62%42%33%49%42%43%36%29%26%
Data source: Saint Sampson September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Saint Sampson in September

As August fades into September in Saint Sampson, Guernsey, the daylight duration begins its graceful descent, offering about 12 hours of daylight this month. This marks a noticeable decline from the peak of 16 hours in June, signaling the transition from summer's vibrant glow to the more muted hues of autumn. Following the steady increase from January’s 8 hours to May’s 15 hours, daylight hours now recede, reflecting nature’s rhythm. As daylight wanes further into October and November, residents are reminded of the cyclical patterns that govern their surroundings, making the most of the softer, shorter days of early autumn.

Average Daylight Hours in Saint Sampson for September

The chart illustrates the variation in daylight duration in Saint Sampson throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 41m10h 7m11h 55m13h 46m15h 21m16h 10m15h 44m14h 19m12h 32m10h 43m9h 5m8h 13m
Data source: Saint Sampson daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Saint Sampson

As summer gently fades into autumn, September in Saint Sampson, Guernsey showcases a noticeable shift in its wind patterns. With an average wind speed of 6.1 m/s (14 mph), September experiences a subtle decline from the summer breezes, reflecting a transition into cooler months. This tapering flush of winds is part of a broader trend, starting with the January peak at 9.0 m/s (20 mph) and gradually diminishing towards the milder summer months, before once again picking up in October. Interestingly, this month’s breeziness is softer than the lively gusts of previous months, inviting a more tranquil atmosphere that perfectly complements the changing colors of the landscape. The friendly September winds serve as a gentle reminder of nature's rhythm, as Guernsey prepares for the stronger gales that will follow in the autumn and winter months.

Average September Wind Speed in Saint Sampson

The chart displays monthly wind speed patterns in Saint Sampson, 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.
JanFebMarAprMayJunJulAugSepOctNovDec9.09.17.86.88.24.66.06.66.1 m/s8.27.89.8
Data source: Saint Sampson September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Saint Sampson Compares to Other Months

Weather in Saint Sampson varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Saint Sampson, focusing on differences in temperature, rainfall, humidity, and UV levels.

September typically offers milder temperatures, with averages around 17°C (62°F) and maximums reaching 21°C (71°F), making it a pleasant transitional month. However, it does experience moderate rainfall, totaling 63 mm (2.5 in) over about 9 days, coupled with a humidity of 76%. In contrast, January is significantly cooler, with an average temperature of just 9°C (49°F) and maximums peaking at 14°C (57°F). This month sees more rain, totaling 94 mm (3.7 in) over 14 days, along with higher humidity at 89%. For a more detailed look at January weather, check out Saint Sampson weather in January.

When comparing the weather in September and February, it's evident that September is generally warmer. With average temperatures reaching around 17°C (62°F) and maximum highs of 21°C (71°F), it offers a more temperate climate than February, whose average temperature is only 9°C (48°F) and peaks at 13°C (56°F). Additionally, February experiences higher humidity levels at 88% and more frequent precipitation, totaling 86 mm (3.4 in) over 16 days, compared to September's 63 mm (2.5 in) across 9 days. For more details on February weather patterns, you can check Saint Sampson weather in February.

September and March display distinctly different weather characteristics. September enjoys milder temperatures, with averages around 17°C (62°F) and highs reaching 21°C (71°F), making it a more pleasant month for outdoor activities. In contrast, March tends to be much cooler, with average temperatures only around 9°C (49°F) and maximums of 13°C (55°F). Precipitation levels are fairly similar, with September receiving 63 mm (2.5 in) over 9 days and March seeing a slight increase to 73 mm (2.9 in) spread over 15 days. Additionally, March exhibits higher humidity at 85%, compared to September's 76%. For more detailed information, you can check Saint Sampson weather in March.

September and April present contrasting weather patterns, with September generally being warmer and drier. In September, temperatures range from a minimum of 12°C (54°F) to a maximum of 21°C (71°F), with an average temperature of 17°C (62°F). This month sees about 63 mm (2.5 in) of precipitation over approximately 9 days, accompanied by a humidity level of 76%. In contrast, April experiences cooler conditions, with temperatures ranging from a minimum of 5°C (41°F) to a maximum of 15°C (59°F), averaging around 10°C (50°F). The total precipitation for April is lower, at 34 mm (1.3 in), occurring over 8 days, but with higher humidity at 84%. For more detailed information on April weather, visit Saint Sampson weather in April.

In September, the weather tends to be warmer, with average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 21°C (71°F), compared to May, which sees temperatures between 7°C (45°F) and 18°C (65°F). Additionally, September experiences slightly higher precipitation at 63 mm (2.5 in) over 9 days, while May records 55 mm (2.2 in) over 8 days. Humidity levels are somewhat lower in September at 76% compared to 81% in May, contributing to a more comfortable feel as the summer draws to a close. For more detailed information about the weather in May, you can check out Saint Sampson weather in May.

In comparing the weather of September and June, September tends to be slightly warmer with an average temperature of 17°C (62°F), as opposed to June's average of 14°C (58°F). Both months experience similar humidity levels, with September at 76% and June slightly higher at 77%. Precipitation is fairly comparable as well, with September receiving 63 mm (2.5 in) over 9 days, while June sees 59 mm (2.3 in) over 8 days. For a detailed look at June weather in Saint Sampson, you can visit Saint Sampson weather in June.

When comparing the weather in September to that of July, we can see several notable differences. In September, temperatures range from a minimum of 12°C (54°F) to a maximum of 21°C (71°F), with an average of 17°C (62°F). This month experiences more precipitation, with 63 mm (2.5 in) over about 9 days, along with higher humidity levels at 76%. In contrast, July has slightly warmer temperatures, with a minimum of 14°C (57°F) and a maximum of 21°C (70°F), while the average remains at 16°C (62°F). July sees less precipitation, totaling 37 mm (1.5 in) across 7 days, and lower humidity at 63%. For those interested in the specifics of July weather, more details can be found here: Saint Sampson weather in July. Overall, September tends to be a bit cooler, wetter, and more humid compared to the drier and slightly warmer month of July.

In September, the weather is slightly cooler compared to August, with average temperatures remaining steady at around 17°C (63°F), but the minimum temperature drops to 12°C (54°F) from August's 14°C (57°F). The maximum temperature also sees a slight decrease, averaging 21°C (71°F) in September, down from 22°C (72°F) in August. Moreover, September experiences more precipitation, with 63 mm (2.5 in) over 9 days, compared to 50 mm (2.0 in) during the same number of rain days in August. The increase in humidity to 76% in September also contributes to a more damp feel than the 71% observed in August. For a more detailed look at the weather trends, you can visit Saint Sampson weather in August.

September and October showcase a notable shift in weather patterns. September tends to be milder, with average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 21°C (71°F), accompanied by around 63 mm (2.5 in) of precipitation over 9 days. In contrast, October experiences cooler temperatures, with averages dipping to a minimum of 9°C (48°F) and a maximum of 20°C (68°F). It also sees a significant increase in rainfall, totaling 144 mm (5.7 in) spread across 17 days, and a rise in humidity to 89%. For more detailed information, you can explore Saint Sampson weather in October.

In September, the weather tends to be milder with average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 21°C (71°F). This month sees relatively less precipitation, totaling 63 mm (2.5 in) over about 9 days, and humidity levels hover around 76%. In contrast, November brings cooler conditions, with temperatures dropping to a minimum of 6°C (43°F) and an average of 12°C (54°F), peaking at 17°C (63°F). The month is significantly wetter, with precipitation reaching 126 mm (5.0 in) across 18 days, and humidity rising to 90%. For a closer look at the weather specifics in November, you can visit Saint Sampson weather in November.

In September, the weather is generally mild, with average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 21°C (71°F). This month experiences about 63 mm (2.5 in) of precipitation over approximately 9 days, accompanied by a humidity level of 76%. In contrast, December presents a much colder and wetter climate, with temperatures dropping to a minimum of 5°C (41°F) and averaging around 11°C (51°F). Moreover, December sees significantly higher precipitation at 163 mm (6.4 in) over 21 days, along with increased humidity at 90%. For a more detailed look at the December weather, you can visit Saint Sampson weather in December.

Compare Saint Sampson's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Saint Sampson

As September unfolds in Saint Sampson, the weather begins to transition, bringing a delightful mix of warmth and mildness that sets it apart from the summer months. With comfortable average temperatures around 17°C and only a modest amount of rainfall, this month strikes a balance between lingering summer vibes and the onset of autumn. The increased humidity, hovering around 76%, adds a touch of softness to the air, creating a cozy atmosphere perfect for strolls along the coastline. While rain may grace about nine days this month, it often gives way to charming, picture-perfect skies, making September a unique and inviting time to experience the beauty of Saint Sampson. To learn more about the seasonal variations in this lovely region, check out Saint Sampson Climate.