Last updated: February 24, 2025
September in Big Bear Lake, United States, offers a delightful mix of late summer warmth and cool mountain breezes. With maximum temperatures reaching 39°C (102°F) and an average of 22°C (71°F), visitors can enjoy plenty of sunny days perfect for outdoor adventures. The evenings cool down, with minimum temps dropping to 7°C (44°F), allowing for cozy nights under the stars. Despite experiencing some rain, with 12 mm (0.5 in) spread over just 2 days, the overall humidity sits at a comfortable 41%, enhancing the fresh mountain air. September is truly a beautiful time to explore the scenic landscapes and vibrant outdoor activities that Big Bear Lake has to offer.
September in Big Bear Lake is a transitional month that showcases the tail end of summer, presenting a delightful range of temperatures. With minimums around 7°C (44°F) and average highs reaching up to a sizzling 39°C (102°F), visitors can expect warm days perfect for outdoor activities. The average temperature hovers around 22°C (71°F), creating ideal conditions for hiking, fishing, and enjoying the lake. As summer gives way to the cooler autumn air, the stark contrast between early and late September embraces a sense of seasonal change, making it an attractive time for those looking to enjoy the beauty of Big Bear before the winter chill sets in.
In September, Big Bear Lake experiences a notable decline in precipitation, averaging just 12 mm (0.5 in) over 2 days. This pattern reflects a broader trend as the region transitions from the summer months to the onset of autumn. Following the relatively higher precipitation of July and August, where rainfall reaches 29 mm (1.1 in) and 19 mm (0.8 in) respectively, September’s reduced figures indicate a shift towards drier conditions. With autumn just around the corner, this light rainfall is typical, hinting at the impending seasonal changes and preparing the landscape for the crisp weather ahead.
September in Big Bear Lake brings a moderate shift in humidity, settling at 41%. This month marks a noticeable increase compared to the dry summer months of July and August, which dip to 29% and 28%, respectively. As summer wanes, the transition toward autumn begins to be felt in the air, with humidity levels aligning more closely with the moderate readings typical in early spring. This gradual rise in moisture foreshadows the cooler, more humid conditions of fall, as the dip seen in the summer ebbs away. Overall, September serves as a refreshing pivot point, paving the way for the chillier months ahead.
As summer winds down in September, the UV Index in Big Bear Lake remains notably high at 10, categorizing it as very high with a burn time of just 15 minutes. This marks a slight decrease from the scorching heights of June and July, where the Index peaked at 12. Despite the transition into fall, residents and visitors should remain vigilant about sun exposure, as the UV Index trends illustrate a gradual tapering from the extreme levels experienced in the summer months. This change highlights the importance of sun safety even in early autumn, reminding everyone that the sun's rays can still be intense. For more detailed information, explore the Big Bear Lake UV Index.
UV Risk Categories
As summer transitions into autumn, September in Big Bear Lake still basks in the warm glow of the sun, offering 322 hours of sunshine. This represents a gentle decline from the peak of sun-drenched July and August, which enjoyed 383 and 363 hours, respectively. The warmth lingers just a bit longer, providing a glorious backdrop for outdoor adventures and scenic hikes. While the days grow shorter as October approaches, September holds onto the vibrant essence of summer, making it an ideal time to enjoy the beautiful landscapes before the cooler months set in.
In Big Bear Lake, September shines as one of the sunniest months, with a remarkable 88% chance of clear skies. This marks a delightful transition from the warm, sun-drenched summer days of August, which enjoys an 82% chance of sun. As summer wraps up, the sunny disposition continues, reflecting a broader trend in the region's climate where the likelihood of sunshine tends to peak during late summer and early fall. This consistent array of sunny days in September not only enhances the beauty of the area but also invites outdoor enthusiasts to relish the breathtaking landscapes and activities that this stunning locale has to offer.
As September unfolds in Big Bear Lake, the days begin to shorten, with a daylight duration of 12 hours. This marks a gradual decline from the vibrant summer months of June and July, which boast 14 hours of sunshine. Following a peak in brightness, August sees a slight decrease, dropping to 13 hours, hinting at the approaching autumn. The transition into fall is palpable, as daylight now dims further, gently guiding the community from the exuberance of summer into the cozy embrace of the coming months. With daylight hours tapering off, September invites reflective moments under the golden hues of early fall, setting the stage for a picturesque seasonal shift.
As September unfolds in Big Bear Lake, the winds begin to whisper a subtle change, with an average speed of 2.0 m/s (4 mph), reflecting a gentle calm that contrasts with the breezier months of spring and early summer. The monthly wind speeds reveal a notable trend: after peaking in April at 2.5 m/s (6 mph), the winds gradually diminish leading into fall. This decrease in wind speed, especially noticeable in August and September, hints at the approaching tranquility of autumn, perfect for savoring the stunning landscapes and serene lakeside views. Whether you're embarking on a peaceful hike or enjoying a cozy afternoon by the water, September's soft breezes in Big Bear Lake create an ideal backdrop for unwinding amidst nature's beauty.
The weather in Big Bear Lake 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 Big Bear Lake and find detailed weather information for every month.
September and January present quite a contrast in weather conditions. In September, temperatures range from a cool 7°C (44°F) to a warm maximum of 39°C (102°F), with an average of 22°C (71°F). The month sees minimal precipitation at just 12 mm (0.5 in) over two days and relatively low humidity at 41%. In stark contrast, January features much colder temperatures, with a minimum of -7°C (19°F) and an average of 7°C (46°F), reaching a maximum of 22°C (72°F). Precipitation increases significantly to 44 mm (1.7 in) over four days, accompanied by higher humidity levels at 76%. For more detailed insights into January weather specifics, you can check out Big Bear Lake weather in January.
September and February present starkly different weather conditions. September boasts warm temperatures, with a minimum of 7°C (44°F) and an average reaching up to 22°C (71°F), peaking at a high of 39°C (102°F). The month experiences relatively low precipitation, averaging just 12 mm (0.5 in) over 2 days, and a humidity level of 41%, creating a dry and comfortable atmosphere. In contrast, February is much cooler, with temperatures dropping to a minimum of -5°C (23°F) and an average of 8°C (46°F), capped at 22°C (72°F). This month sees significantly more precipitation at 46 mm (1.8 in) over 5 days and a higher humidity level of 80%, which can create a much chillier and wetter environment. For more details on February weather, you can check Big Bear Lake weather in February.
In September, temperatures in Big Bear Lake can range from a refreshing minimum of 7°C (44°F) to a scorching maximum of 39°C (102°F), with an average of 22°C (71°F). The month sees relatively low precipitation, averaging just 12 mm (0.5 in) over about 2 days, and the humidity remains at a comfortable 41%. In contrast, March experiences much cooler conditions, with minimum temperatures dipping to -4°C (25°F) and a max of 27°C (81°F), leading to an average of only 9°C (49°F). This month is wetter, with total precipitation of 42 mm (1.6 in) spread across roughly 7 days and significantly higher humidity at 69%. For more detailed insights, you can explore Big Bear Lake weather in March.
September and April showcase contrasting weather patterns, marked by significant differences in temperature and humidity. September typically enjoys warmer conditions, with average temperatures reaching up to 22°C (71°F) and highs soaring to 39°C (102°F). In contrast, April presents a cooler atmosphere, with average temperatures around 14°C (57°F) and a maximum of 30°C (86°F). Additionally, while September has lower humidity at 41% and minimal precipitation of only 12 mm (0.5 in) over two days, April experiences a higher humidity level of 57% and increased precipitation at 21 mm (0.8 in) over the same period. For more specific insights on April weather, visit Big Bear Lake weather in April.
When comparing the weather between September and May, notable differences emerge. In September, temperatures can soar, with highs reaching up to 39°C (102°F) and average temperatures around 22°C (71°F), making it a warmer month overall. In contrast, May has cooler temperatures, with a minimum of 1°C (33°F) and an average of 16°C (61°F), peaking at 33°C (92°F). Precipitation is similar, but May experiences slightly more rain over an additional day, totaling 14 mm (0.6 in) compared to September's 12 mm (0.5 in). Additionally, humidity levels are slightly higher in May at 45%, compared to September's 41%. For more details on weather conditions, you can check Big Bear Lake weather in May.
When comparing the weather in September and June, both months exhibit similar average temperatures, hovering around 22°C (72°F), with minimums in the mild range of 7°C (44°F). However, September presents a wider temperature range with maximums reaching up to 39°C (102°F), while June peaks at a modest 37°C (99°F). Precipitation is more common in September with 12 mm (0.5 in) over 2 days compared to June's lighter rainfall of just 5 mm (0.2 in) over 1 day. Additionally, September tends to be a bit more humid at 41% versus June’s 34%, which contributes to a distinct difference in comfort levels. For a closer look at June weather specifics, visit Big Bear Lake weather in June.
In comparing the weather of September and July, we notice some distinct differences. September boasts a wider temperature range, with minimums dropping to 7°C (44°F) and maximums reaching up to 39°C (102°F), while July maintains a milder minimum of 11°C (52°F) and a peak of 38°C (101°F). Additionally, September experiences less precipitation, with only 12 mm (0.5 in) over just 2 days, in stark contrast to July’s 29 mm (1.1 in) spread over 6 days. Interestingly, despite September being warmer on average at 22°C (71°F), it has a higher humidity level at 41%, compared to July’s 29%. For more detailed information, you can check out Big Bear Lake weather in July.
In comparing the weather between September and August, September tends to be slightly cooler, with average temperatures ranging from a minimum of 7°C (44°F) to a maximum of 39°C (102°F), compared to August's higher average of 25°C (77°F) with a minimum of 12°C (55°F) and a maximum of 37°C (98°F). While August has more humidity at 28% and a higher precipitation level of 19 mm over five days, September offers a drier climate, with only 12 mm of precipitation over just two days and a relative humidity of 41%. For a detailed look at conditions during August, you can visit Big Bear Lake weather in August.
September weather is characterized by warmer temperatures, with minimums around 7°C (44°F) and maximums reaching up to 39°C (102°F), averaging at 22°C (71°F). The month experiences limited rainfall, totaling 12 mm (0.5 in) over just 2 days, accompanied by relatively low humidity at 41%. In contrast, October sees a noticeable drop in temperatures, with minimums falling to 2°C (36°F) and an average of 16°C (61°F), peaking at a maximum of 33°C (92°F). Although October has less total precipitation at 8 mm (0.3 in) over just 1 day, the humidity increases to 54%, making the air feel a bit more crisp and moist. For more specific details about October weather, you can check Big Bear Lake weather in October.
September weather is characterized by warm temperatures, with a minimum of 7°C (44°F) and an average high of 22°C (71°F), reaching up to a scorching 39°C (102°F) on warmer days. In contrast, November brings a significant drop in temperatures, with a minimum of -3°C (27°F) and an average high of just 12°C (54°F). While September experiences relatively low humidity at 41%, November's humidity increases to 68%, contributing to a cooler feel in the air. Additionally, November sees slightly more precipitation at 16 mm (0.6 in) over the same number of days as September, which only received 12 mm (0.5 in). For more details, check out Big Bear Lake weather in November.
September weather in Big Bear Lake features a wide range of temperatures, with minimums reaching 7°C (44°F) and maximums soaring up to 39°C (102°F), while averaging a comfortable 22°C (71°F). This month typically experiences low precipitation, only about 12 mm (0.5 in) over just 2 days, and a humidity level of 41%. In contrast, December brings much colder conditions, with temperatures dropping significantly—minimums can plunge to -7°C (19°F), and the average temperature is only around 7°C (46°F), with maximums reaching 22°C (71°F). The month also sees increased precipitation, totaling 45 mm (1.8 in) over 4 days, alongside a much higher humidity level of 75%. To learn more about the specific weather conditions in December, check out Big Bear Lake weather in December.
As September graces Big Bear Lake, the weather begins its gentle transition from the warm summer days toward the cooler embrace of autumn. With temperatures averaging a comfortable 22°C (71°F), this month offers a delightful mix of sunny afternoons and cooler evenings, making it ideal for outdoor activities. Unlike the height of summer, when the heat can be intense, September sees a more moderate climate with minimal rainfall, boasting only 12 mm (0.5 in) across just two days. As the humidity drops to about 41%, the crispness in the air signals the approach of fall, making it a perfect time to explore the breathtaking landscapes of the area. For a deeper understanding of what to expect throughout the year, check out the Big Bear Lake Climate page.