Last updated: February 24, 2025
In September, Bozeman experiences a dynamic range of temperatures, with maximums reaching up to 33°C (92°F) and minimums dipping to -4°C (25°F). The monthly average temperature sits comfortably at 12°C (54°F), making it a transitional period as summer fades into fall. With precipitation totaling 59 mm (2.3 in) across 7 days, residents and visitors can expect a blend of sunny spells and occasional rain. Humidity levels hover around 67%, adding to the rich atmospheric conditions typical of this vibrant Montana locale. Whether exploring the outdoors or enjoying a cozy indoor setting, September in Bozeman showcases the beauty of seasonal change.
As summer gracefully transitions to fall, September in Bozeman offers a unique blend of warmth and crispness. With minimum temperatures averaging around -4°C (25°F) and daytime highs reaching up to 33°C (92°F), residents and visitors experience a delightful range of temperatures. The month provides a gentle reminder of the impending winter, as the average temperature settles at a comfortable 12°C (54°F). This fluctuation in temperatures not only creates perfect conditions for outdoor adventures but also enhances the vibrant autumn foliage, making September a picturesque time to enjoy the breathtaking landscapes that Bozeman has to offer.
In September, Bozeman experiences a moderate precipitation total of 59 mm (2.3 in), marking a shift towards wetter conditions as summer draws to a close. This month sees rain on 7 days, contributing to the gradual increase in moisture that typically follows August's drier spell. Compared to previous summer months, September's precipitation stands out, indicating a noteworthy transition as the region prepares for the cooler fall. This uptick in rainfall mirrors the overall pattern of increasing precipitation leading into autumn, emphasizing the shift in weather dynamics that residents can expect as they bid farewell to summer's warmth.
As summer fades and September arrives in Bozeman, the city experiences a notable decline in humidity, reaching about 67%. This marks a significant drop from the warm, more humid days of July and August, which average around 74% and 69%, respectively. The trend showcases a comfortable transition into autumn, where the air becomes crisper and less heavy, inviting outdoor activities and cozy gatherings. While humidity levels will begin to rise again in the cooler months of October and November, the September decline brings a refreshing change that residents and visitors alike can appreciate.
As summer transitions into fall, Bozeman experiences a notable shift in UV Index, with September maintaining a very high rating of 8. This level signals the need for caution, as the recommended burn time is just 15 minutes—similar to the previous month, which underscores the lingering effects of summer sun exposure. Throughout the year, the UV Index peaks during the intense months of May and June, showing an extreme rating of 11, while earlier months are less intense with moderate levels. As September draws to a close, the anticipation of lower levels in October begins, yet it's essential to remain vigilant during this time. To learn more about the UV Index trends in Bozeman, visit Bozeman UV Index.
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Bozeman basks in the warm glow of September sunshine, boasting 277 hours of sunlight that signals the gentle transition from summer's golden days to autumn's crisp embrace. Following the peak of July, with its impressive 389 hours of sunlight, the sunlight begins to mellow, but September retains a generous amount. This month stands in contrast to the earlier part of the year, where winter's somber grip sees January lagging at just 145 hours. As summer fades, the abundance of sunlight slowly recedes, yet September remains a vibrant month for outdoor activities, framed by the breathtaking landscapes of the Rockies. With each passing month, Bozeman’s rich tapestry of light serves as a reminder of nature's cycles, inviting residents and visitors alike to savor those lingering sunny days before the chill of October sets in.
As summer fades and fall approaches, September in Bozeman offers a delightful blend of warmth and sunshine, boasting a 70% chance of sunny weather. This marks a significant uptick from the cooler months, where January and February see less than 40% sunny days, and is a refreshing contrast to the spring months, which hover around the mid-40s. The sun-soaked days of summer, particularly in June and July with chances around 74% and 67% respectively, pave the way for September to maintain a vibrant glow as the season transitions. With the shift towards autumn, September presents a golden opportunity to enjoy the outdoors before the winter chill sets in, making it one of the ideal times to bask under Bozeman's inviting skies.
As September arrives in Bozeman, the daylight hours begin to wane, marking a transition from the summer’s longer days to the impending chill of autumn. With approximately 12 hours of daylight, September retains a comfortable luminosity, though it’s a notable decrease from the 14 hours experienced in August. This gradual reduction reflects a larger trend throughout the year, where daylight peaks in the summer months of June and July at 15 hours, before tapering off into shorter days as winter approaches. The ebb and flow of daylight is not just a rhythm of time; it is a canvas that paints each season with its own unique character, inviting residents and visitors alike to savor the lingering warmth of early autumn before the days grow noticeably shorter.
As summer transitions to autumn in Bozeman, the September wind carries a gentle reminiscence of the warmer months, with an average speed of 2.1 m/s (5 mph). This consistency in wind patterns reflects a notable stability throughout the year, with September's gusts mirroring those found in August and March. Interestingly, the wind begins to pick up slightly in the following months, as the air cools and the surroundings start to shift toward winter. Overall, the mild breezes of September offer a refreshing, yet familiar experience, bridging the gap between the vibrant energy of summer and the crispness of fall.
The weather in Bozeman 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 Bozeman and find detailed weather information for every month.
September weather is characterized by a wide temperature range, with minimums around -4°C (25°F) and maximums reaching up to 33°C (92°F). The average temperature is a more moderate 12°C (54°F), accompanied by relatively low humidity at 67% and total precipitation of 59 mm (2.3 in) over about 7 days. In contrast, January brings much colder conditions, where temperatures can plummet to a minimum of -29°C (-20°F) and rarely rise above 6°C (43°F), with an average of -7°C (20°F). The month features higher humidity levels at 93% and less precipitation overall, totaling 30 mm (1.2 in) across approximately 8 days. For a closer look at January weather specifics, you can check out Bozeman weather in January.
September and February present stark contrasts in weather conditions. In September, temperatures can range dramatically from a chilly -4°C (25°F) to a scorching 33°C (92°F), with an average of 12°C (54°F) and relatively lower humidity at 67%. In contrast, February plunges into much colder temperatures, with minimums reaching -36°C (-32°F) and an average of -8°C (18°F), while the maximum barely rises to 9°C (48°F). The precipitation levels are similar, with September receiving 59 mm (2.3 in) over 7 days, while February sees 65 mm (2.5 in) spread across 14 days, often accompanied by higher humidity at 92%. For a closer look at the February conditions, check out Bozeman weather in February.
Comparing the weather in September and March reveals significant contrasts in temperature and overall conditions. September experiences a wide temperature range, with minimums around -4°C (25°F) and maximums reaching a warm 33°C (92°F), averaging at a comfortable 12°C (54°F). This month sees moderate precipitation at 59 mm (2.3 in) over about 7 days, along with a humidity level of 67%.
In contrast, March is markedly colder, with minimum temperatures plummeting to -28°C (-18°F) and maximums only reaching 16°C (61°F), resulting in an average temperature of -2°C (29°F). Despite receiving less precipitation at 47 mm (1.8 in), March experiences rainfall or snow on about 11 days, accompanied by a higher humidity level of 89%. For a more detailed outlook into March’s weather, you can read more about Bozeman weather in March.
When comparing the weather of September and April, September tends to have a warmer temperature range, with a minimum of -4°C (25°F) and a maximum of 33°C (92°F), while April's temperatures can drop to a chilly minimum of -20°C (-4°F) and reach a maximum of 22°C (72°F). Precipitation levels are higher in April, totaling 86 mm (3.4 in) over 15 days compared to September's 59 mm (2.3 in) over just 7 days, along with a higher average humidity of 83% in April versus 67% in September. For more detailed information, you can check Bozeman weather in April.
When comparing the weather in September and May, there are notable differences in temperature, precipitation, and humidity. September boasts a wider temperature range with minimums of -4°C (25°F) and maximums reaching up to 33°C (92°F), resulting in an average of 12°C (54°F). In contrast, May experiences cooler temperatures, with minimums around -10°C (13°F) and maximums peaking at 25°C (77°F), yielding an average of just 8°C (46°F).
Precipitation levels are also higher in May, with 102 mm (4.0 in) over 18 days, compared to September's 59 mm (2.3 in) spread over only 7 days. Humidity is slightly higher in May at 79%, compared to September's 67%. For more detailed insights, you can check Bozeman weather in May.
September and June exhibit some interesting weather similarities and differences. Both months can see maximum temperatures reaching as high as 33°C (92°F), but September has a wider temperature range, with minimums dropping down to -4°C (25°F), compared to June’s minimum of 0°C (32°F). Precipitation is notably higher in June, with an average of 104 mm (4.1 in) over 14 days, whereas September sees less rainfall, totaling 59 mm (2.3 in) across 7 days. Additionally, humidity levels are higher in June at 76%, compared to 67% in September. For more detailed insights, check out Bozeman weather in June.
In comparing the weather between September and July, we can see notable differences in temperature and precipitation patterns. September experiences a wider temperature range, with minimums dropping to -4°C (25°F) and maximums reaching up to 33°C (92°F), while July typically has milder minimums starting at 0°C (33°F) and slightly higher maximums peaking at 34°C (94°F). Precipitation is more frequent in September, with an average of 59 mm (2.3 in) over 7 days, compared to July, which sees 39 mm (1.5 in) across 8 days. Humidity levels are also slightly lower in September at 67%, compared to July's 74%. For more details on July's weather in Bozeman, check out Bozeman weather in July.
In comparing the weather patterns of September and August, we see distinct variations. September experiences a broader range of temperatures, with a minimum of -4°C (25°F) and an average of 12°C (54°F), while August's temperatures are generally milder, ranging from a minimum of 2°C (36°F) to an average of 17°C (64°F). Both months share the same maximum temperature of 33°C (92°F), yet September sees slightly higher precipitation at 59 mm (2.3 in) over 7 days, compared to August's 48 mm (1.9 in) over 8 days. Humidity levels are similar, with September at 67% and August slightly higher at 69%. For more details on the conditions in August, you can check Bozeman weather in August.
In comparing the weather between September and October, it’s clear that October experiences significantly cooler temperatures. While September boasts an average temperature of 12°C (54°F) with maximum highs reaching up to 33°C (92°F), October's average temperature drops to 3°C (38°F) and can plummet to a minimum of -27°C (-17°F). Additionally, October sees a slight increase in precipitation, with 68 mm (2.7 in) over 13 days, compared to September's 59 mm (2.3 in) over 7 days. The humidity also rises slightly from 67% in September to 72% in October. For more detailed insights into October's climate, check out Bozeman weather in October.
In September, temperatures can vary widely, with minimums dipping to -4°C (25°F) and maximums reaching a warm 33°C (92°F). The month typically sees an average temperature of 12°C (54°F) and experiences around 59 mm (2.3 in) of precipitation over about 7 days, with humidity levels at 67%. In contrast, November brings much colder weather, featuring significantly lower temperatures with a minimum of -22°C (-7°F) and an average of -2°C (28°F), while the maximum temperature sits at a milder 19°C (66°F). Precipitation in November is slightly lower at 50 mm (2.0 in), but it occurs over more days, approximately 11, contributing to increased humidity levels at 89%. For more insights, you can check Bozeman weather in November.
September and December showcase stark contrasts in weather. September experiences a much warmer climate with average temperatures around 12°C (54°F), peaking at 33°C (92°F), while December plunges to an average of -7°C (20°F), with highs only reaching 14°C (57°F). The humidity in December is notably higher at 94%, compared to September's 67%, contributing to a chillier feel despite less precipitation—37 mm (1.5 in) over 10 days in December versus 59 mm (2.3 in) over 7 days in September. For a more detailed look at the December climate, you can check Bozeman weather in December.
As summer transitions into autumn, September in Bozeman reveals a remarkable shift in weather patterns. Residents and visitors experience more moderate temperatures, with pleasant days that gradually cool down as the month progresses. This month stands out with its unique blend of warmth and crispness, contrasting sharply with the sweltering summers or the chill of winter months. Precipitation becomes more frequent, but the overall humidity remains comfortable, making September a delightful time for outdoor activities and enjoying the stunning fall colors. For a deeper understanding of what to expect throughout the year, explore the full details at Bozeman Climate.