September Weather in Sunapee, United States

Last updated: February 24, 2025

September in Sunapee, United States, offers a vibrant transition from summer to fall. With maximum temperatures reaching 32°C (89°F), visitors can still enjoy warm days, while the average temperature settles comfortably at 17°C (62°F). As the month progresses, nighttime temperatures can dip to a cool -2°C (28°F), marking the change of seasons. Rainfall is also a feature, with approximately 65 mm (2.6 in) spread over 8 days, contributing to the lush surroundings that define this picturesque locale. The humidity lingers around 71%, adding to the rich, refreshing atmosphere that characterizes September in Sunapee.

September Temperature in Sunapee

As September unfolds in Sunapee, United States, the transition from summer to fall becomes palpable, with temperatures showcasing a comfortable range. The minimum temperature hovers around -2°C (28°F), offering a crisp start to the month, while average highs reach a pleasant 32°C (89°F), allowing for lingering warmth reminiscent of summer days. With an average temperature of 17°C (62°F), September serves as a bridge, inviting residents and visitors alike to enjoy outdoor activities amid stunning autumn foliage. This month marks a noticeable cooling trend, setting the stage for the cooler days ahead, yet it still retains the warmth of late summer, making it an ideal time for exploration and appreciation of nature’s changing palette.

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

The chart illustrates September temperature patterns in Sunapee, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec222531435666716962503626
Data source: Temperature data for Sunapee 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 Sunapee

In September, Sunapee experiences a decline in precipitation, with only 65 mm (2.6 in) of rainfall over a modest 8 days. This marks a noticeable reduction compared to the wetter summer months, particularly July, which recorded 125 mm (4.9 in) over 13 days. As the region transitions from summer to fall, the drier conditions in September hint at the upcoming changes in weather patterns, setting the stage for October's rebound with its 129 mm (5.1 in) forecasted precipitation. This trend underscores a typical seasonal shift, where the warm summer rains give way to the crisp, cooler air of autumn, influencing both the landscape and local activities as nature begins to prepare for winter.

September Precipitation Trends in Sunapee

The chart displays monthly precipitation patterns in Sunapee, 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.
JanFebMarAprMayJunJulAugSepOctNovDec70827512183911259065129106109
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Sunapee

In September, Sunapee's humidity reaches a comfortable 71%, marking a slight increase from the summer's lower levels of around 66% in August. This subtle rise indicates a transition as the region begins to shift from the warmest months of the year. Throughout the year, humidity levels exhibit a notable pattern: they start high in winter, with January peaking at 86%, and gradually decrease to their lowest point in the summer, reaching 67% in July. As autumn approaches, humidity begins to creep back up, hinting at the return of cooler, moister air characteristic of the upcoming months. This seasonal rhythm not only shapes Sunapee's climate but also influences its vibrant and lush landscape.

September Average Humidity in Sunapee

This chart illustrates the average monthly humidity levels in Sunapee, 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.
JanFebMarAprMayJunJulAugSepOctNovDec86%84%82%80%72%72%67%66%71%79%84%81%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Sunapee

As September arrives in Sunapee, the UV Index reflects a shift towards high levels of sun exposure, registering at 7. This decrease from the peak values of 9 in the summer months signals a transition, allowing for a slightly longer burn time of 25 minutes compared to just 15 minutes during the height of summer. Nonetheless, with the index still in the high category, it remains essential to take precautions to protect your skin. As daylight hours begin to wane, the changing seasons serve as a reminder of the importance of staying informed about sun safety. For up-to-date UV Index information and tips, visit Sunapee UV Index.

Maximum UV Index Levels in Sunapee for September

The chart shows the monthly maximum UV Index (UVI) for Sunapee 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.
JanFebMarAprMayJunJulAugSepOctNovDec3458910997532
Data source: Sunapee 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 Sunapee

As summer's warmth gradually fades, September in Sunapee offers a delightful retreat with 288 hours of sunshine, a gentle decline from the peak radiance of July and August. This transition marks a shift in the seasons, as the crisp air heralds the onset of autumn while still basking in the afterglow of summer's extended daylight. The overall trend reveals a steady increase in sunshine hours from January’s modest 136 hours, climbing higher through the months until reaching late summer's pinnacle. As fall approaches, the contrast between the vibrant summer glow and the coming cooler days becomes not just a reminder of the changing seasons but a charming invitation to savor the picturesque landscapes painted with autumn hues.

Monthly Sunshine Duration in Sunapee: September Highlighted

The September sunshine duration represents the total number of hours Sunapee 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.
JanFebMarAprMayJunJulAugSepOctNovDec136h168h242h224h271h320h325h333h288h200h175h163h
Data source: Sunapee September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Sunapee During September

When considering the likelihood of sunny weather in September in Sunapee, United States, one can observe a notable trend. As summer winds down, September boasts a 40% chance of sunshine, a slight uptick from the muggier months of July and August, which see only 25% and 29% chances, respectively. This increase suggests a transition into a more pleasant climate, reminiscent of the 52% chance in March, marking the arrival of clearer skies as autumn approaches. September's sunny potential stands out among the preceding months, offering residents and visitors alike a delightful opportunity to enjoy the crisp fall air under the sun.

Percentage of Sunny Days in September in Sunapee

The chart illustrates the percentage of sunny days in Sunapee 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 Sunapee experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec35%28%53%35%34%38%26%29%40%33%48%26%
Data source: Sunapee September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Sunapee in September

As September unfolds in Sunapee, the days begin to shorten, with an average of 12 hours of daylight—a gentle decline from the peak brightness of 15 hours in the summer months of June and July. This transition marks a significant shift as the vibrant summer glow gradually gives way to the crisper autumn air. In September, while the days still feel warm and inviting, they hint at the upcoming coolness of fall, mirroring the trend of diminishing daylight that continues into October, where sunlight dips to just 10 hours. With each passing day, the rhythm of seasons becomes more palpable, reminding residents and visitors alike of nature's cyclical beauty.

Average Daylight Hours in Sunapee for September

The chart illustrates the variation in daylight duration in Sunapee throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 21m10h 30m11h 58m13h 27m14h 43m15h 20m15h13h 52m12h 26m10h 57m9h 39m8h 59m
Data source: Sunapee daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Sunapee

As summer gently transitions into autumn, the September winds in Sunapee reveal a subtle yet significant shift. With an average wind speed of 2.8 m/s (6 mph), September experiences a slight uptick compared to the more tranquil gusts of July and August, which saw their lowest speeds of 2.4 m/s (5 mph) and 2.2 m/s (5 mph), respectively. This refreshing breeze not only signals the onset of fall but also hints at the approach of crisper days ahead. Overall, September stands out as a pivotal moment in the year, bridging the slower summer winds with the invigorating breezes that characterize the coming months, encouraging outdoor explorations amidst the changing foliage.

Average September Wind Speed in Sunapee

The chart displays monthly wind speed patterns in Sunapee, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.43.13.93.32.93.02.42.22.8 m/s2.73.03.2
Data source: Sunapee September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Sunapee Compares to Other Months

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

September and January present strikingly different weather conditions. September boasts milder temperatures, with a minimum of -2°C (28°F) and an average of 17°C (62°F), peaking at a warm 32°C (89°F). In contrast, January brings frigid weather, where temperatures can plunge to a minimum of -30°C (-21°F), averaging around -6°C (22°F) and reaching a maximum of just 15°C (59°F). While both months experience similar levels of precipitation—65 mm (2.6 in) in September and 70 mm (2.8 in) in January—January is characterized by higher humidity at 86% compared to September's 71%. For more details on January conditions, check out Sunapee weather in January.

September and February exhibit stark contrasts in weather patterns. In September, temperatures range from a chilly -2°C (28°F) at night to a warm 32°C (89°F) during the day, with an average of 17°C (62°F). The month experiences moderate precipitation, totaling 65 mm (2.6 in) over approximately 8 days, and maintains a humidity level of 71%. In contrast, February is marked by much colder conditions: temperatures plummet to a minimum of -28°C (-17°F) and only reach a maximum of 22°C (71°F), averaging -4°C (25°F). This winter month sees slightly higher precipitation at 82 mm (3.2 in) across around 11 days, alongside increased humidity at 84%. For detailed insights about the remarkable weather in February, you can check Sunapee weather in February.

September and March exhibit contrasting weather patterns, reflecting the transition between late summer and early spring. In September, temperatures range from a chilly minimum of -2°C (28°F) to a warm maximum of 32°C (89°F), with an average of 17°C (62°F) and relatively moderate humidity at 71%. The month experiences about 65 mm (2.6 in) of precipitation over approximately 8 days. In stark contrast, March presents a much colder climate, with temperatures dropping as low as -20°C (-3°F) and peaking at 21°C (70°F), averaging around 0°C (32°F). Precipitation in March slightly increases to 75 mm (2.9 in) and occurs on about 9 days, accompanied by higher humidity levels at 82%. The differences in temperature and precipitation between these two months illustrate the significant seasonal shifts. For more details on March conditions, you can check Sunapee weather in March.

September and April exhibit notable differences in weather patterns. September enjoys a broader temperature range, with a minimum of -2°C (28°F) and a pleasant average of 17°C (62°F), peaking at 32°C (89°F). In contrast, April's temperatures are generally cooler, featuring a minimum of -7°C (20°F) and an average of 6°C (44°F), with a maximum of 26°C (80°F). Additionally, September experiences less precipitation at 65 mm (2.6 in) over 8 days, while April has a higher rainfall amount of 121 mm (4.8 in) over 12 days. Humidity levels are slightly lower in September at 71%, compared to April's 80%. For a more detailed look at what to expect, visit Sunapee weather in April.

When comparing the weather in September and May, we see distinct differences in temperature and precipitation patterns. September typically features a wider temperature range, with minimums dropping to -2°C (28°F) and maximums climbing to 32°C (89°F), yielding an average of 17°C (62°F). In contrast, May has slightly milder temperatures, with minimums around -1°C (31°F) and maximums peaking at 33°C (91°F), resulting in an average temperature of 13°C (56°F). Precipitation is more frequent in May, with 83 mm (3.3 in) recorded over 12 days compared to September's 65 mm (2.6 in) over 8 days. Humidity levels are similar, hovering around 71% for September and 72% for May. For more detailed information, you can check Sunapee weather in May.

In comparing the weather of September and June, we see notable differences in both temperature and precipitation. September offers a wider temperature range, with a minimum of -2°C (28°F) and a maximum reaching 32°C (89°F), while June’s temperatures are generally milder, with a minimum of 2°C (36°F) and a maximum of 35°C (95°F). Precipitation levels are higher in June, totaling 91 mm (3.6 in) over 12 days compared to September's 65 mm (2.6 in) spread over just 8 days. Interestingly, both months exhibit similar humidity levels, with September at 71% and June slightly higher at 72%. For more detailed information about June's climate, you can check Sunapee weather in June.

In comparing the weather of September to that of July, September tends to have a wider temperature range, with minimums dropping to -2°C (28°F) and maximums reaching up to 32°C (89°F), while July remains consistently warmer with minimums around 9°C (48°F) and highs peaking at 35°C (96°F). September experiences less precipitation than July, receiving about 65 mm (2.6 in) over 8 days compared to July's 125 mm (4.9 in) spread over 13 days. Additionally, while humidity levels in September average around 71%, July maintains a slightly lower average at 67%. This highlights a transition towards cooler and drier conditions as summer gives way to early autumn. For more specific insights, you can check Sunapee weather in July.

In comparing the weather of September and August, September showcases a wider temperature range, with minimums dipping to -2°C (28°F) and maximums reaching 32°C (89°F), resulting in an average temperature of 17°C (62°F). In contrast, August tends to be warmer overall, with minimum temperatures around 7°C (45°F) and a higher average of 21°C (69°F), peaking at 35°C (94°F). Additionally, precipitation levels in August are greater, totaling 89 mm (3.5 in) across 10 days, compared to September’s 65 mm (2.6 in) over 8 days. Humidity remains relatively similar, with September at 71% and August slightly lower at 66%. For a detailed look at the weather specifics, check Sunapee weather in August.

September typically enjoys milder temperatures, with an average of 17°C (62°F) and a maximum reaching up to 32°C (89°F). The month sees about 65 mm (2.6 in) of precipitation over 8 days, with a humidity level of 71%. In contrast, October marks a distinct shift in weather, featuring cooler average temperatures around 10°C (50°F) and a maximum of 26°C (79°F). This month experiences increased precipitation of 129 mm (5.1 in) spread over 12 days, along with higher humidity at 78%. For more detailed information, check out Sunapee weather in October.

In September, the weather is relatively mild with temperatures ranging from a minimum of -2°C (28°F) to a maximum of 32°C (89°F), averaging around 17°C (62°F). This month sees moderate precipitation of 65 mm (2.6 in) over about 8 days, coupled with a humidity level of 71%. In contrast, November brings much cooler conditions, characterized by a minimum temperature of -18°C (0°F) and an average of just 2°C (36°F), peaking at 23°C (73°F). The month experiences higher precipitation at 106 mm (4.2 in) across approximately 12 days, accompanied by increased humidity at 84%. For more details on the weather during this month, check out Sunapee weather in November.

September and December present stark contrasts in weather. In September, temperatures range from a chilly -2°C (28°F) at night to a warm average of 17°C (62°F) during the day, reaching highs of 32°C (89°F). With an average precipitation of 65 mm (2.6 in) over 8 days and a humidity level of 71%, September feels decidedly mild. In contrast, December brings much colder conditions, with temperatures dipping to a minimum of -25°C (-13°F) and averaging around -3°C (26°F), with a maximum of 15°C (59°F). This month also sees increased precipitation at 109 mm (4.3 in) spread over 9 days and higher humidity at 81%. For more detailed weather insights, you can check Sunapee weather in December.

Compare Sunapee's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Sunapee

As summer gives way to autumn, September in Sunapee brings a delightful shift in the weather patterns. With pleasantly mild temperatures, the month encapsulates a perfect blend of warm days and cooler nights, making it an ideal time for outdoor activities. While the air remains humid, the rainfall is moderate, allowing for vibrant fall foliage to emerge. This transitional month stands out from the harsher winters and the heat of summer, marking a beautiful period of change. To explore more about the weather trends throughout the year, visit Sunapee Climate.