September Weather in Estes Park, United States

Last updated: February 24, 2025

In September, Estes Park, United States experiences a dynamic climate characterized by a maximum temperature reaching up to 30°C (86°F), while the average settles around a mild 11°C (53°F). Nights can be chilly, dipping to a minimum of -8°C (18°F), making this month a blend of warm days and cool evenings. The region sees 58 mm (2.3 in) of rainfall over 11 days, contributing to a 63% humidity level that enhances the freshness in the air. Whether you're exploring the stunning landscapes or enjoying local festivities, the varied weather adds a unique charm to this beautiful mountain town.

September Temperature in Estes Park

As summer transitions to autumn, Estes Park experiences a shift in temperatures during September that beautifully captures the essence of early fall. With minimums dipping to -8°C (18°F) and averages settling at a comfortable 11°C (53°F), the crisp mountain air starts to signal the change of seasons. The days can still feel quite warm, reaching up to 30°C (86°F), inviting outdoor adventures amidst stunning fall foliage. This month serves as a delightful bridge, showcasing the last remnants of summer warmth before the chill of winter sets in, making it a perfect time for both exploration and relaxation in this picturesque mountain town.

September Weather in Estes Park: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Estes Park, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec212028334255605853373024
Data source: Temperature data for Estes Park 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 Estes Park

In September, Estes Park experiences a notable transition as summer wanes, marked by an average precipitation of 58 mm (2.3 in) over approximately 11 days. This amount reflects a significant dip compared to the preceding months of July and August, which are characterized by higher rainfall, peaking at 152 mm (6.0 in) and 114 mm (4.5 in), respectively. The cooler weather starts to set in, leading to fewer precipitation days as fall approaches, creating a serene atmosphere perfect for enjoying the stunning autumn foliage. Overall, September serves as a gentle reminder of the seasonal shift, with diminished rainfall yet an enchanting beauty that draws visitors to this picturesque destination.

September Precipitation Trends in Estes Park

The chart displays monthly precipitation patterns in Estes Park, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2944757514512715211458513728
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Estes Park

As September settles into Estes Park, the humidity remains steady at 63%, mirroring the slightly higher levels of the preceding summer months. This consistency suggests a gradual transition from the drier climate of summer, where July and August experience 62% and 63% humidity respectively, towards the more moisture-laden autumn months. Notably, this makes September feel pleasantly mild, especially compared to the peak humidity seen in winter, which averages around 84% in January. As the year progresses, one can expect a gradual uptick in humidity, culminating in the winter months that often feel significantly more humid. This trend towards increased humidity in the colder months captures the essence of Estes Park's changing seasons and invites visitors to experience the unique beauty of the region throughout the year.

September Average Humidity in Estes Park

This chart illustrates the average monthly humidity levels in Estes Park, 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.
JanFebMarAprMayJunJulAugSepOctNovDec84%86%75%67%67%68%62%63%63%72%80%85%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Estes Park

As September rolls into Estes Park, the UV Index begins to reflect a notable decline from the peak summer months, yet it still holds a significant position with a value of 10, categorizing it as very high. As the days grow shorter and cooler, the burn time extends slightly to 15 minutes, indicating a need for sun protection, especially during midday. This trend highlights a gradual tapering of extreme exposure levels seen in mid-summer, yet it serves as a reminder that even into autumn, the sun's rays can be fierce. For tips on staying safe under the sun, visit Estes Park UV Index.

Maximum UV Index Levels in Estes Park for September

The chart shows the monthly maximum UV Index (UVI) for Estes Park 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.
JanFebMarAprMayJunJulAugSepOctNovDec469121213121110754
Data source: Estes Park 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 Estes Park

September in Estes Park greets visitors with a delightful 311 hours of sunshine, making it a splendid time to explore the breathtaking landscapes. As summer gradually transitions into fall, the sunlight begins to soften, offering a warm glow that enhances the vibrant hues of the changing leaves. Notably, September stands out with fewer sunshine hours compared to the peak of summer, which boasts 386 hours in July, but it still surpasses the earlier months of the year like January, which only sees 186 hours. This moderate sunshine creates an inviting atmosphere for outdoor activities, whether hiking the famed trails or enjoying a quiet picnic in the park. With September’s balance of daylight and cooler temperatures, it’s an ideal month for those looking to savor the beauty of Estes Park before the winter chill sets in.

Monthly Sunshine Duration in Estes Park: September Highlighted

The September sunshine duration represents the total number of hours Estes Park 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.
JanFebMarAprMayJunJulAugSepOctNovDec186h234h289h307h341h380h386h355h311h275h247h236h
Data source: Estes Park September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Estes Park During September

In Estes Park, September marks a delightful transition to sunnier days, with a 66% chance of sunshine, making it one of the sunniest months of the year. This trend of increasing sunny weather is evident as we move from the cooler, cloudy winter months into the warmer summer season, where the chances of clear skies gradually rise from 51% in January to a peak of 63% in August. Following this sunny peak, September holds onto the bright vibes, showcasing the area's charm amid the beginnings of fall. As autumn approaches, the likelihood of sunshine remains relatively high, offering visitors the perfect opportunity to explore the stunning landscapes and vibrant foliage that define this unique time of year.

Percentage of Sunny Days in September in Estes Park

The chart illustrates the percentage of sunny days in Estes Park 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 Estes Park experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec51%43%49%50%40%54%58%63%66%58%59%57%
Data source: Estes Park September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Estes Park in September

As summer transitions to fall in Estes Park, September marks a gentle decline in daylight duration, with the sun gracing the skies for approximately 12 hours. This shift follows the peak summer months of June, July, and August, where daylight reached a delightful 14 hours. As the days gradually shorten, we begin to witness autumn's approach, highlighted by a fading light that soon leads into the crisp days of October with 11 hours of daylight. This trend underscores the natural rhythm of the seasons in Estes Park, offering a perfect backdrop for the vibrant fall colors that the area is renowned for.

Average Daylight Hours in Estes Park for September

The chart illustrates the variation in daylight duration in Estes Park throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 39m10h 40m11h 58m13h 18m14h 26m14h 59m14h 41m13h 41m12h 24m11h 4m9h 55m9h 19m
Data source: Estes Park daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Estes Park

In Estes Park, September ushers in a gentle breeze with an average wind speed of 2.1 m/s (5 mph), reflecting a continuation of the mild conditions typical of the late summer months. As the seasons transition, this slight dip from the higher summer speeds suggests a calming of the winds, inviting outdoor enthusiasts to savor the stunning autumn views without the interruption of stronger gusts. Interestingly, September's winds are consistent with those of July and August, maintaining a serene atmosphere as nature begins to shift towards the vibrant hues of fall. As the month progresses, one can almost feel the anticipation of October's brisker winds, which average around 2.8 m/s (6 mph), hinting at the seasonal changes ahead.

Average September Wind Speed in Estes Park

The chart displays monthly wind speed patterns in Estes Park, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.43.32.52.42.02.12.12.22.1 m/s2.83.53.8
Data source: Estes Park September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Estes Park Compares to Other Months

The weather in Estes Park 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 Estes Park and find detailed weather information for every month.

In comparing the weather between September and January, significant differences emerge. September experiences a wider temperature range, with minimums around -8°C (18°F), averages of 11°C (53°F), and maximums reaching 30°C (86°F), accompanied by moderate humidity at 63% and a total precipitation of 58 mm (2.3 in) over 11 days. In contrast, January brings much colder temperatures, with minimums plummeting to -27°C (-17°F) and averages of -6°C (22°F), peaking at a maximum of only 8°C (47°F). The month has lower precipitation totals at 29 mm (1.1 in) over just 6 days but features higher humidity at 84%. For more detailed insights, explore Estes Park weather in January.

September and February exhibit stark contrasts in weather. In September, temperatures range from a chilly -8°C (18°F) at night to a warm 30°C (86°F) during the day, with an average of 11°C (53°F). The month sees a moderate level of precipitation at 58 mm (2.3 in) over 11 days and boasts a relatively comfortable humidity of 63%. In contrast, February is far colder, with temperatures dipping as low as -29°C (-19°F) and averaging -7°C (20°F), peaking at just 13°C (55°F). Although February has slightly less precipitation at 44 mm (1.7 in) over the same number of days, it experiences a much higher humidity level of 85%. For a detailed look at February weather in Estes Park, you can check Estes Park weather in February.

When comparing the weather in September and March, significant differences become evident. September typically boasts a milder climate with temperatures ranging from a minimum of -8°C (18°F) to a maximum of 30°C (86°F), while March features much colder conditions, with temperatures dipping as low as -23°C (-8°F) and only reaching a maximum of 15°C (59°F). Precipitation levels are also noteworthy; September sees about 58 mm (2.3 in) over 11 days, while March has a slightly higher total of 75 mm (2.9 in) spread over 12 days. Additionally, March tends to have higher humidity at 75%, compared to September's 63%. For a more in-depth look at the March weather specifics, you can check Estes Park weather in March.

September and April present distinct weather patterns, each with unique characteristics. In September, temperatures range from a minimum of -8°C (18°F) to a maximum of 30°C (86°F), with an average of 11°C (53°F) and a total precipitation of 58 mm (2.3 in) over 11 days. This month enjoys relatively higher warmth and lower humidity at 63%. In contrast, April experiences colder temperatures, ranging from -21°C (-5°F) to a maximum of 17°C (63°F), with an average of just 1°C (33°F). It sees more precipitation at 75 mm (3.0 in) over the same number of rainy days, and a slightly higher humidity level of 67%. For more details on the weather in this month, check out Estes Park weather in April.

When comparing the weather in September and May, notable differences emerge in temperature and precipitation patterns. September boasts a wider temperature range, with minimums around -8°C (18°F) and maximums reaching 30°C (86°F), leading to an average of 11°C (53°F). In contrast, May tends to be cooler, starting with minimum temperatures of -14°C (7°F) and capping at 23°C (74°F), averaging around 6°C (42°F). Additionally, May experiences significantly more rainfall, with 145 mm (5.7 in) over 20 days compared to September’s 58 mm (2.3 in) across 11 days. Both months feature moderate humidity, with May at 67% and September slightly lower at 63%. For more details about the weather conditions, check out Estes Park weather in May.

September and June offer distinct weather experiences. In September, temperatures range from a chilly -8°C (18°F) at night to a warm 30°C (86°F) during the day, with an average of 11°C (53°F). The month sees moderate precipitation of 58 mm (2.3 in) over 11 days, resulting in a humidity level of 63%. In contrast, June is slightly milder, with temperatures ranging from -3°C (27°F) to 29°C (84°F) and an average temperature of 13°C (55°F). However, June is notably wetter, receiving 127 mm (5.0 in) of rain spread over 19 days, leading to a higher humidity of 68%. For a detailed look at June conditions, you can check Estes Park weather in June.

When comparing the weather in September and July, we see distinct differences in temperature, precipitation, and overall conditions. September experiences a greater temperature range, with minimums dipping to -8°C (18°F) and maximums reaching up to 30°C (86°F), resulting in an average of 11°C (53°F). In contrast, July remains warmer, with minimum temperatures around 2°C (36°F) and an average of 16°C (60°F), complemented by a maximum of 29°C (84°F). Additionally, September sees less precipitation, totaling 58 mm (2.3 in) over 11 days, whereas July has significantly higher rainfall at 152 mm (6.0 in) over 22 days, leading to a wetter month overall. Both months feature similar humidity levels, with September at 63% and July slightly lower at 62%. For a deeper dive into July weather specifics, visit Estes Park weather in July.

In comparing the weather between September and August, it is evident that September features a broader temperature range, with minimums dipping to -8°C (18°F) and maximums reaching up to 30°C (86°F). This displays a shift towards cooler nights and warmer days compared to August, which has a minimum of 2°C (36°F) and a maximum of 28°C (82°F). Additionally, September experiences significantly less precipitation, totaling 58 mm (2.3 in) over 11 days, whereas August sees a wetter month with 114 mm (4.5 in) recorded over 17 days. Both months maintain a consistent humidity level of 63%, but the clearer skies and reduced rain in September offer a more pleasant outdoor experience. For more details on August weather, you can visit Estes Park weather in August.

September features a wider temperature range, with minimums around -8°C (18°F) and maximums soaring up to 30°C (86°F), making it a more variable month with an average of 11°C (53°F). The humidity sits at a comfortable 63%, and the month sees about 58 mm (2.3 in) of precipitation over 11 days. In contrast, October presents a more consistent chill, with minimum temperatures dropping to -22°C (-7°F) and an average temperature of only 3°C (38°F), peaking at a milder 22°C (72°F). Precipitation slightly decreases to 51 mm (2.0 in) over just 8 days, while humidity rises to 72%, indicating a dampening of the air. For more specific details about the October climate, check Estes Park weather in October.

September and November weather present a stark contrast in temperature and conditions. In September, temperatures range from a minimum of -8°C (18°F) to a maximum of 30°C (86°F), with an average of 11°C (53°F) and relatively moderate humidity at 63%. The month experiences around 58 mm (2.3 in) of precipitation over 11 days. In comparison, November ushers in much colder temperatures, with lows plummeting to -23°C (-9°F) and an average of -1°C (30°F), peaking at 16°C (62°F). Additionally, November sees increased humidity at 79% but less precipitation, totaling 37 mm (1.4 in) over just 6 days. For a more detailed look at November conditions, check out Estes Park weather in November.

In September, the weather is quite mild with temperatures ranging from a minimum of -8°C (18°F) to a maximum of 30°C (86°F), averaging around 11°C (53°F). This month experiences 58 mm (2.3 in) of precipitation over 11 days, all while maintaining a moderate humidity level of 63%. In contrast, December brings much colder conditions, with temperatures dipping to a minimum of -25°C (-13°F) and peaking at only 15°C (60°F), averaging -5°C (24°F). Precipitation is lighter at 28 mm (1.1 in) over just 7 days, but humidity is higher at 85%. For a closer look at the December weather, you can visit Estes Park weather in December.

Compare Estes Park's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Estes Park

As summer fades into autumn, September in Estes Park showcases a unique transition in its weather patterns. The days can still be quite warm, offering a pleasant contrast to the chilly nights that dip toward freezing. With an average temperature of around 11°C, visitors can enjoy the crisp air while experiencing noteworthy precipitation on about 11 days of the month. This moderate humidity level creates a refreshing atmosphere, making September a delightful time to explore the stunning natural beauty of the region. For a deeper understanding of what to expect this month and to compare with seasonal trends, check out the detailed insights at Estes Park Climate.