Last updated: February 24, 2025
September in Grand Junction, United States, showcases a dynamic weather profile, with temperatures typically ranging from a brisk 0°C (33°F) to a high of 35°C (96°F), resulting in a pleasant average of 19°C (66°F). This month also brings about a modest 40 mm (1.6 in) of precipitation over approximately 6 days, contributing to a relative humidity of 53%. As summer transitions into fall, the weather presents a perfect opportunity for outdoor activities, making September an ideal time to explore the stunning landscapes of this region.
As September rolls into Grand Junction, a delightful transition in temperatures signals the arrival of autumn. With minimums settling around 0°C (33°F), the days start off crisp, while average highs reach a pleasant 19°C (66°F). The landscape basks in the warmth of the sun, peaking at 35°C (96°F), reminiscent of late summer, yet hinting at the coolness to come. This month marks a significant shift from the scorching highs of July and August, reflecting a broader cooling trend leading into October. Residents and visitors alike can relish the comfortable weather, making September a charming time to enjoy outdoor activities against the backdrop of changing foliage.
In September, Grand Junction experiences a notable consistency in its precipitation levels, with 40 mm (1.6 in) of rain falling over an average of 6 days. This marks a return to the monthly totals seen earlier in the year, reminiscent of January and May. Although not as wet as the peak months of March and October, September serves as a bridge between the summer dryness of June and August and the more substantial rains of fall. As autumn approaches, the precipitation levels suggest a gradual increase in moisture, setting the stage for the wetter months ahead, while maintaining a balanced rhythm in the region's overall climate.
In September, Grand Junction experiences a noticeable shift in humidity, reaching 53% as the summer months wane. This marks an increase from the low of 39% observed in both July and August, signaling a gradual return to milder conditions. The trend throughout the year reveals a pattern where winter and early spring months are quite humid, with levels peaking at 90% in January and 89% in February, while the summer months bring drier air, culminating in the driest period of 39% humidity in July and August. As the region transitions into autumn, September's humidity hints at a comforting change, preceding the more humid fall months of October and November, which see significant climbs back up to 72% and 84%, respectively.
As the summer months wane, September in Grand Junction, United States, sees a slight dip in the UV Index, shifting down to 10, categorized as very high. This indicates that while the scorching days of summer are behind us, sun safety remains crucial, with a burn time of just 15 minutes under direct sunlight. The considerable UV exposure trend from June through August, where we reached extreme levels of 12 and 11, highlights the importance of protective measures during the peak sun months. As we transition into fall, the UV Index will continue to decline, leading into October's more moderate levels. For detailed information on UV trends throughout the year, visit Grand Junction UV Index.
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As summer wanes and September unfolds in Grand Junction, the region continues to bask in the warmth of a generous 315 hours of sunshine, a delightful capstone to the sunny season. Following the peak of sunshine during the summer months, which boasts 382 hours in both June and July, September shows a gentle decline while still outpacing many earlier months. The sunlit days of autumn not only offer a vibrant backdrop for outdoor activities but also hint at the crisp, cooler weather to come, contrasting with the lively brightness of the preceding summer. As the year progresses, sunlight hours steadily recede, with October bringing 278 hours, framing September as a bridge between the carefree days of summer and the serene embrace of autumn.
As September rolls in, Grand Junction enjoys an impressive 75% chance of sunny weather, marking it as one of the sunniest months of the year. Following the warm and bright days of August, which boasts a 73% likelihood of sunshine, September continues this trend, providing ideal conditions for outdoor activities and festivities. The steady increase in sunny days throughout the summer months leads seamlessly into the fall, where sunshine can often be a pleasant surprise against the backdrop of changing leaves. With September's luminous days and refreshing evenings, it’s the perfect time to soak in the last rays of summer before the cooler months arrive.
As the summer fades, September in Grand Junction marks a gentle transition with an average of 12 hours of daylight. Following the sun-drenched heights of June, July, and August, which basked in a consistent 14 hours, September signals the beginning of shorter days ahead. The month serves as a bridge, easing away from the long summer days while still offering ample sunlight for outdoor activities and enjoying the changing foliage. As daylight gradually decreases, one can feel the subtle shift toward autumn, with October bringing even shorter days at 11 hours. This trend sets the stage for cozy evenings and the vibrant colors that fall brings to the landscape.
In Grand Junction, the September winds offer a gentle sigh as summer transitions into fall, with an average wind speed of 1.8 m/s (4 mph). This slight breeze maintains the modest wind patterns observed throughout the year, contributing to a comfortable atmosphere ideal for outdoor activities. After a peak in May at 2.5 m/s (6 mph), the winds gradually soften, hinting at the calmness of autumn. Notably, September's wind speed mirrors that of October, creating a consistent and soothing backdrop as the landscape begins to shift in color, reflecting the subtle rhythms of the changing seasons. As September draws to a close, the calming winds encapsulate the serene beauty of Grand Junction during this captivating month.
The weather in Grand Junction 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 Grand Junction and find detailed weather information for every month.
In September, the weather is significantly warmer, with temperatures ranging from a minimum of 0°C (33°F) to a maximum of 35°C (96°F), averaging around 19°C (66°F). The humidity is a comfortable 53%, and the month typically sees about 40 mm (1.6 in) of precipitation over 6 days. In contrast, January presents a starkly different climate, with much colder temperatures that can drop as low as -23°C (-9°F) and only reach a maximum of 12°C (54°F), averaging -4°C (24°F). The humidity is much higher at 90%, and although it also receives approximately 40 mm (1.6 in) of precipitation, this occurs over 7 days, creating a noticeably different winter atmosphere. For more detailed insights on January weather, you can visit Grand Junction weather in January.
In September, temperatures are much milder, ranging from a minimum of 0°C (33°F) to a maximum of 35°C (96°F), with an average of 19°C (66°F). This month sees relatively low precipitation, averaging 40 mm (1.6 in) over about 6 rainy days, and the humidity is around 53%. In stark contrast, February experiences harsher winter conditions, with temperatures plummeting as low as -23°C (-10°F) and peaking at only 14°C (57°F), averaging -2°C (29°F). Despite the colder temperatures, February has a slightly higher precipitation level of 49 mm (1.9 in), occurring over 9 days, and features increased humidity at 89%. For more detailed insights, check out Grand Junction weather in February.
When comparing the weather in September and March, the differences are quite stark. September features a more temperate climate with average temperatures around 19°C (66°F) and a maximum of 35°C (96°F), making it generally warm and pleasant. In contrast, March tends to be much colder, with average temperatures of only 4°C (39°F) and lows reaching as low as -17°C (2°F). Additionally, precipitation is higher in March, with a total of 69 mm (2.7 in) over 11 days compared to September's 40 mm (1.6 in) over just 6 days. Humidity levels also rise in March, averaging 81% compared to September's 53%, suggesting a significant shift in weather conditions from summer to late winter. For more details on the specific conditions in March, you can check Grand Junction weather in March.
September and April in Grand Junction present distinct weather characteristics that highlight the transition between summer and autumn, as well as winter and spring. In September, temperatures can reach highs of 35°C (96°F), bringing warm days with an average of 19°C (66°F) and a relatively low humidity of 53%. In contrast, April experiences cooler conditions, with average temperatures around 9°C (49°F), maximums of 27°C (81°F), and more pronounced humidity at 74%. Additionally, while September has 40 mm (1.6 in) of precipitation over approximately 6 days, April tends to be slightly drier with 33 mm (1.3 in) spread over 8 days. For more details about April weather in Grand Junction, you can visit Grand Junction weather in April.
When comparing the weather in September and May, we see notable differences in temperature, precipitation, and humidity. September boasts a warm average temperature of 19°C (66°F), with highs reaching up to 35°C (96°F), while May is slightly cooler, with an average of 15°C (59°F) and a maximum of 32°C (90°F). Precipitation levels are fairly comparable, with September receiving 40 mm (1.6 in) over about six days, while May has slightly more rain at 42 mm (1.7 in) across eight days. Humidity levels are also a tad higher in May at 58%, compared to 53% in September. For a closer look at the climate in May, you can visit Grand Junction weather in May.
When comparing the weather in September to June, we see notable differences in temperature and precipitation patterns. September experiences a more significant range, with temperatures ranging from a chilly 0°C (33°F) to a warm 35°C (96°F), averaging around 19°C (66°F). It also sees more precipitation, with 40 mm (1.6 in) falling over about 6 days. In contrast, June tends to be warmer, with minimum temperatures of 2°C (37°F) and maximums reaching 38°C (100°F), averaging 22°C (72°F). Additionally, June is drier, receiving only 26 mm (1.0 in) of precipitation over just 4 days. Overall, while both months can be quite warm, September tends to be slightly cooler and wetter compared to June. For more details, check out Grand Junction weather in June.
In comparing the weather between July and September, July tends to be warmer, with an average temperature of 25°C (77°F) and maximum highs reaching 38°C (101°F). In contrast, September sees a broader temperature range, with minimums dropping to 0°C (33°F) and average temperatures around 19°C (66°F), making it generally cooler than July. Additionally, September experiences slightly more precipitation at 40 mm (1.6 in) over about 6 days, whereas July has 34 mm (1.3 in) over 7 days. Humidity levels also differ, with September averaging 53% compared to July's lower 39%. For a more detailed insight, you can check out Grand Junction weather in July.
In comparing the weather between August and September, September experiences a wider temperature range, with minimum temperatures dropping to 0°C (33°F) compared to August's milder low of 8°C (46°F). While the average temperature in September is slightly cooler at 19°C (66°F) than August’s 23°C (74°F), it still sees maximum temperatures similar to August, reaching up to 35°C (96°F) versus 36°C (97°F). Precipitation levels increase in September, with 40 mm (1.6 in) of rain over 6 days, compared to 29 mm (1.1 in) over 5 days in August. Additionally, September has a higher humidity level at 53%, compared to August's 39%. For more detailed weather statistics specific to that month, you can refer to Grand Junction weather in August.
September typically displays warmer weather with average temperatures around 19°C (66°F) and a maximum of 35°C (96°F), while October experiences a notable drop in temperatures, averaging 9°C (49°F) and peaking at 27°C (81°F). While September encounters less precipitation at 40 mm over 6 days, October sees a rise in rainfall to 55 mm across 8 days. Additionally, the humidity increases significantly in October, reaching 72%, compared to a more comfortable 53% in September. For further details on October weather, visit Grand Junction weather in October.
September and November present strikingly different weather patterns. In September, temperatures are much warmer, with a minimum of 0°C (33°F) and an average of 19°C (66°F), peaking at a high of 35°C (96°F). This month also sees a moderate amount of precipitation at 40 mm (1.6 in) over six days, along with a humidity level of 53%. In contrast, November experiences a significant drop in temperature, with minimums falling to -16°C (4°F) and an average of just 4°C (39°F), while highs reach only 20°C (68°F). The month is relatively drier, with precipitation of 23 mm (0.9 in) over four days, but the humidity is considerably higher at 84%. For more specific details on the weather in November, visit Grand Junction weather in November.
In September, the weather is generally warm, with temperatures ranging from a chilly 0°C (33°F) to a hot 35°C (96°F) and an average of 19°C (66°F). The month experiences about 40 mm (1.6 in) of precipitation over approximately 6 days, and humidity sits at a moderate 53%. In contrast, December brings a much colder climate, with temperatures plummeting to a minimum of -22°C (-8°F) and an average temperature of -3°C (28°F), peaking at 15°C (59°F). Precipitation levels are slightly lower at 37 mm (1.5 in) over 7 days, but the humidity significantly increases to 90%. This stark difference in weather highlights the transition from the warmth of early autumn to the frigid chill of winter. For more specific details about December weather, you can refer to Grand Junction weather in December.
As September arrives in Grand Junction, the weather transitions from the sweltering summer heat to a more moderate climate. With average temperatures settling comfortably around 19°C (66°F), this month provides a refreshing break from the peak summer highs that can reach up to 35°C (96°F). While September does experience some rainfall—averaging around 40 mm over six days—the humidity remains relatively moderate at 53%, making outdoor activities enjoyable. Whether you’re hiking in the crisp air or enjoying the beautiful fall colors, September offers a delightful shift that invites exploration and adventure. For a deeper dive into the area's climate, check out Grand Junction Climate.