Last updated: February 24, 2025
In September, Three Rivers, United States experiences a remarkable climate characterized by a wide temperature range, where maximum temperatures can soar to 40°C (104°F), while the average remains a comfortable 23°C (73°F). On the cooler side, minimum temperatures drop to 7°C (44°F), providing a refreshing contrast. With only 4 mm (0.2 in) of precipitation recorded across the month and zero days of rainfall, the atmosphere remains predominantly dry, complemented by a humidity level of 42%. This unique combination of conditions makes September an ideal time for outdoor activities amidst the vibrant natural scenery of the region.
In Three Rivers, United States, September marks a transitional period as summer begins to wane. With minimum temperatures averaging around 7°C (44°F) and maximums peaking at a sweltering 40°C (104°F), the month retains a sense of summer's warmth while hinting at the onset of autumn. The average temperature stabilizes at approximately 23°C (73°F), creating a comfortable climate for outdoor activities. This month notably contrasts with the preceding summer, where July and August saw their max temperatures soar to 41°C (105°F). As the days start to shorten and crispness creeps into the air, September offers a beautiful balance of summer's heat and autumn's cooler embrace, setting the stage for the seasonal change ahead.
In September, Three Rivers experiences a notable dry spell, recording only 4 mm (0.2 in) of precipitation over the course of the month, yet no measurable rain falls on any of the days. This stark contrast to the wetter months preceding it, particularly March, where 196 mm (7.7 in) fell over 14 days, highlights a clear trend of declining moisture as summer transitions into fall. Moving from the lush rainfall of early in the year to the near-zero totals of July and August, September signifies a significant shift in the weather pattern, setting the stage for the more variable precipitation typical of the autumn months ahead. As the year progresses, October and November begin to redistribute some rainfall, but September stands out as a month of pronounced dryness.
In September, the humidity in Three Rivers, United States, sits at a comfortable 42%, marking a noteworthy increase from the dry summer months that saw levels drop to a mere 30% in August. This slight rise signifies the gradual transition into fall, as humidity levels begin to move back towards the higher averages typically seen in the earlier months of the year. January and February showcase the peak of moisture in the air, reaching upwards of 82% and 85%, respectively. Following these wet winter months, a clear downward trend dominates late spring and summer, dipping to its lowest in July. Thus, September serves as a reminder of the seasonal shift, where humidity starts to reclaim its presence, gradually paving the way for the wetter months ahead.
In September, Three Rivers experiences a very high UV Index of 9, indicating that sun exposure can lead to skin damage in as little as 15 minutes. This trend follows a summer peak, where UV levels reached an extreme 11 in both June and July, emphasizing the importance of sun safety during the warm months. While the UV Index begins to decline in October, moving to a high category of 7 with a longer burn time of 25 minutes, the September sun still requires caution and protective measures. As awareness of UV exposure grows, it's essential for residents and visitors to stay informed and take the necessary precautions. For more detailed information, check out the Three Rivers UV Index.
UV Risk Categories
As summer gently fades into autumn, September in Three Rivers is a radiant affair with 316 hours of sunshine. Building on the sun-kissed days of August, which boasted 361 hours, September sees a noticeable decline but retains a generous offering of bright skies. This consistent glow from May through September showcases a remarkable trend, where each month leading into the fall contributes increasingly to the overall warmth and sunshine. With June and July peaking at 384 and 388 hours, respectively, the sunlight begins to wane, yet September's still-bright days remind us of summer’s linger, offering a perfect backdrop to embrace the changing season. As the year progresses towards its end, sunlight continues to diminish, suggesting a gradual transition into winter’s embrace, but for now, September shines as a beautiful bridge from summer to autumn.
In September, Three Rivers witnesses a remarkable 93% chance of sunny days, marking it as one of the sunniest months of the year. This vibrant period follows the peak of summer, with August leading at an impressive 94%. As the seasons transition from summer to autumn, the likelihood of sunny weather remains consistently high, significantly outpacing the more cloud-prone winter months like December, which dips to just 44%. With such a strong probability of beautiful weather, September is an ideal time to enjoy outdoor activities and bask in the golden hues of early fall in Three Rivers.
As summer transitions into autumn, September in Three Rivers sees a gentle decline in daylight, averaging around 12 hours of sunlight. This marks a slight reduction from the previous month, where residents enjoyed 13 hours of bright summer days. The waning daylight signals the onset of fall, with October expected to bring even less sunlight. Throughout the year, a noticeable trend emerges: daylight gradually increases from the 9 hours of January, peaks in the vibrant months of May to July at 14 hours, and then gradually decreases as we head back toward winter. This rhythmic ebb and flow of daylight not only defines the seasons but also enriches the cultural and recreational activities of the community, creating a dynamic interplay between nature and daily life.
As September dawns in Three Rivers, the wind begins to pick up slightly, averaging 1.6 m/s (4 mph), which is a notable increase from the more subdued breezes of summer. This gentle elevation in wind speed marks a transition, as nature prepares for the cooler months ahead. Compared to the preceding months, where the average hovered around 1.5 m/s (3 mph), September’s breezy conditions offer a refreshing hint of autumn and serve as a precursor to the slower, calmer winds of October, which average back down to 1.5 m/s (3 mph). This subtle fluctuation not only invigorates the atmosphere but also hints at a shift in the seasonal rhythm, inviting everyone to step outside and savor the crisp, invigorating air.
The weather in Three Rivers 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 Three Rivers and find detailed weather information for every month.
September and January present a stark contrast in weather. In September, temperatures range from a mild 7°C (44°F) at night to a scorching 40°C (104°F) during the day, with an average of 23°C (73°F) and minimal precipitation of just 4 mm. The humidity is relatively low at 42%, creating a warm and dry atmosphere. In contrast, January sees much cooler temperatures, with lows reaching -5°C (23°F) and a daytime average of only 8°C (47°F). Precipitation dramatically increases to 144 mm over 8 days, contributing to a much higher humidity level of 82%. For more detailed information about January weather, you can visit Three Rivers weather in January.
September and February present a stark contrast in weather conditions. September boasts much warmer temperatures, ranging from a chilly 7°C (44°F) at night to a scorching high of 40°C (104°F) during the day, with low humidity at 42% and virtually no precipitation. In contrast, February experiences much colder weather, with temperatures dropping as low as -8°C (18°F) and averaging just 8°C (47°F), alongside significant precipitation of 154 mm (6.1 in) spread over 10 wet days, coupled with high humidity levels of 85%. For a more detailed look at February's weather patterns, visit Three Rivers weather in February.
September and March display strikingly different weather patterns. In September, temperatures range from a cool 7°C (44°F) at night to a scorching 40°C (104°F) during the day, with minimal precipitation and low humidity at 42%. In contrast, March experiences much colder temperatures, with a minimum of -5°C (24°F) and a maximum of 26°C (79°F), but it is significantly wetter, boasting 196 mm (7.7 in) of precipitation over 14 days, and a much higher humidity level of 80%. For a more detailed look at the weather in March, you can visit Three Rivers weather in March.
When comparing the weather in September and April, notable differences emerge. September boasts a much warmer temperature range, with averages around 23°C (73°F) and maximums reaching up to 40°C (104°F), while April sees cooler conditions, with an average of 14°C (57°F) and highs of 29°C (84°F). Moreover, September is characterized by dry weather, with virtually no precipitation and low humidity at 42%. In contrast, April experiences significant rainfall of 78 mm (3.1 in) over six days and higher humidity levels at 72%. For a more extensive look at the April climate in this region, you can visit Three Rivers weather in April.
In September, temperatures range from a minimum of 7°C (44°F) to a scorching maximum of 40°C (104°F), with an average of 23°C (73°F). The month is characterized by minimal precipitation, with only 4 mm (0.2 in) and no recorded rainy days, alongside a lower humidity level of 42%. In contrast, May experiences cooler temperatures, with a minimum of 3°C (38°F), an average of 17°C (63°F), and a maximum of 34°C (93°F). This month is considerably wetter, receiving 45 mm (1.8 in) of rainfall over four days, and has a higher humidity of 58%. For a detailed look into May weather, you can visit Three Rivers weather in May.
In comparing the weather of September and June, both months exhibit similar average temperatures, with September featuring a minimum of 7°C and a maximum of 40°C, while June has a slightly higher minimum of 8°C and a maximum of 39°C. Interestingly, both months experience minimal precipitation, with September recording just 4 mm and June only 2 mm, and neither month seeing any rainy days. However, September is somewhat drier, with lower humidity at 42% compared to June's 49%, making it feel slightly more comfortable despite the higher maximum temperature. For more detailed insights, you can check out Three Rivers weather in June.
In comparing the weather of September and July, we observe notable differences. September exhibits a broader temperature range, with minimums dipping to 7°C (44°F) and maximums peaking at 40°C (104°F), while averaging at 23°C (73°F). In contrast, July is warmer overall, starting at a minimum of 14°C (57°F) and averaging 27°C (81°F), but also reaching a maximum of 40°C (105°F). Both months experience very little precipitation, with September recording just 4 mm (0.2 in) and July almost none, at only 1 mm (0.0 in). Interestingly, September is slightly more humid, sitting at 42%, compared to July's 36%. For a closer look at July weather specifics, you can check Three Rivers weather in July.
In comparison to August, September experiences a more varied temperature range, with minimums dropping to 7°C (44°F) and maximums reaching up to 40°C (104°F), while August's temperatures generally hover between a minimum of 15°C (59°F) and a maximum of 41°C (105°F). The average temperature in September is slightly lower at 23°C (73°F) compared to August's 26°C (80°F). Additionally, September benefits from lower humidity at 42%, whereas August's humidity is recorded at 30%. Both months report minimal precipitation, with September receiving just 4 mm (0.2 in) and August receiving a mere 1 mm (0.0 in), with no rainy days in either month. For more details about August weather, visit Three Rivers weather in August.
September weather is characterized by relatively high temperatures, with average highs reaching up to 40°C (104°F) and an average of 23°C (73°F). It's a dry month, experiencing no precipitation and lower humidity levels at 42%. In contrast, October brings a noticeable drop in temperatures, with average lows of 2°C (36°F) and highs of 33°C (91°F), resulting in an average of 17°C (63°F). The month also sees increased precipitation, totaling 17 mm (0.7 in) over one day, along with higher humidity at 59%. For a more detailed look at October weather in the area, you can visit Three Rivers weather in October.
September and November showcase a stark contrast in weather conditions. September boasts warmer temperatures, with an average of 23°C (73°F) and a maximum reaching up to 40°C (104°F), accompanied by low humidity at 42% and virtually no precipitation. In contrast, November experiences much cooler weather, with an average temperature of 12°C (54°F), a minimum dipping to -6°C (21°F), and a maximum of 26°C (80°F). This month also sees increased humidity at 78% and significantly higher precipitation levels, totaling 52 mm (2.1 in) over four days. For more detailed insights, check Three Rivers weather in November.
September and December present contrasting weather experiences. In September, temperatures soar with a minimum of 7°C (44°F), averaging a warm 23°C (73°F), and reaching a peak of 40°C (104°F). The month sees minimal precipitation at just 4 mm (0.2 in) and boasts low humidity levels of 42%, offering a dry and hot atmosphere. In stark contrast, December brings much cooler temperatures, with a minimum of -4°C (25°F) and an average of 8°C (47°F), not exceeding 22°C (73°F). The month is significantly wetter, receiving 100 mm (3.9 in) of precipitation over 9 days, along with higher humidity levels at 79%, creating a damp and chilly environment. For more details, check out Three Rivers weather in December.
In September, Three Rivers experiences a notable shift in weather patterns, characterized by warm days and crisp nights. Unlike the sweltering peaks of summer, where temperatures soar, September offers a comfortable average of 23°C (73°F), making outdoor activities enjoyable. With minimal precipitation and no rainy days, the month boasts a dry climate that contrasts sharply with the wetter seasons ahead. As humidity settles at a manageable 42%, the pleasant evenings invite cozy gatherings under clear skies. For a deeper understanding of how this picturesque month fits into the region's overall climate, explore our detailed page on Three Rivers Climate.