Last updated: February 24, 2025
In September, Mendocino, United States experiences a delightful range of temperatures, with a maximum reaching up to 36°C (96°F) and a comfortable average of 18°C (64°F). Nights can be cool, dipping to a minimum of 8°C (47°F), creating a refreshing contrast. This month sees minimal rainfall, totaling just 6 mm (0.2 in) over the course of a single day, making it ideal for outdoor activities. With humidity levels hovering around 68%, the air carries a pleasant warmth, inviting visitors and locals alike to enjoy the stunning coastal scenery and vibrant community.
September in Mendocino, United States, marks a significant transition in temperatures as summer winds down. With minimums around 8°C (47°F) and averages peaking at 18°C (64°F), the climate remains comfortably warm, making it an ideal time for outdoor enjoyment. However, the standout feature is the remarkable maximum temperature soaring to 36°C (96°F), the highest in the year, showcasing the area’s capacity for late-season heat. This month serves as a delightful blend of lingering summer warmth and the onset of cooler autumn evenings, creating a unique atmosphere perfect for exploring the beautiful coastal landscapes. As September progresses, the gradual shift towards cooler days begins, heralding the arrival of fall in this picturesque region.
In Mendocino, September marks a subtle transition as summer wanes, bringing a modest precipitation of 6 mm (0.2 in), measured over just one day. This slight uptick in rainfall is a stark contrast to the dry spell of the previous months, where June, July, and August recorded virtually no rain. The summer months typically feature minimal precipitation, with July and August seeing less than 1 mm, emphasizing Mendocino's characteristic dry season. As the region prepares for autumn, this early September rain hints at the gradual return of moisture, setting the stage for the increased rainfall that usually follows in October and the subsequent months, ultimately revitalizing the lush landscapes for which Mendocino is known.
As September rolls into Mendocino, the coastal city experiences a slight uptick in humidity, reaching 68%, a modest increase from the drier summer months of June (76%), July (70%), and August (66%). This rise hints at the approach of fall, as the humidity gradually makes its way back towards the higher levels characteristic of the winter months. The transition is subtle but noticeable, with the humidity levels in September starting to climb towards the 84% mark that dominates the region during the winter months of November and December. This trend underscores Mendocino's dynamic climate, where summer's aridness gives way to the moisture-laden atmosphere of autumn and winter, creating an ever-changing, captivating environment.
In September, Mendocino experiences a UV Index of 8, categorizing it as very high exposure, with a burn time of just 15 minutes. This marks a slight decrease from the intense UV levels of May through August, which consistently hovered at 11. As summer fades, the UV Index begins to taper off, yet September still demands caution due to its significant potential for sunburn. This trend suggests that while the warmth of summer lingers, it's essential to remain vigilant about sun protection as we transition into the fall. For more details about the UV Index fluctuations throughout the year, visit Mendocino UV Index.
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As summer gracefully transitions into fall, September in Mendocino offers a delightful balance of warmth and brightness, boasting 302 hours of sunshine. This month, while slightly less sun-soaked than the peak of July, still reflects a significant seasonal shift, showcasing the region’s characteristic charm. Following the bustling summer months, where July and August shine with 386 and 344 hours respectively, September maintains a robust glow that invites visitors to relish the lingering warmth of summer while hints of autumn begin to peek through. The gradual decline in sunshine hours signals the approach of October, which brings a cozy ambiance with 275 hours of sunlight. Thus, September serves as a perfect bridge, blending the vibrant energy of summer with the gentle coziness of fall, creating an inviting backdrop for both exploration and relaxation.
September in Mendocino ushers in a moderate likelihood of sunny weather, with the sun peeking through about 57% of the time. This marks a slight dip from the sunny heights of August, which boasts a 63% chance of clear skies. Interestingly, while the summer months typically promise more sunshine, September maintains a respectable average, nestled comfortably between the 70% of May and the 56% seen in June. As the season transitions into fall, the gradual reduction in sunny days hints at the upcoming cooler months, yet September still offers a delightful balance of warmth and brightness for those looking to enjoy the outdoors.
As summer transitions into fall, September in Mendocino offers a gentle reduction in daylight, providing about 12 hours of sunlight—a slight decline from the 13 hours of August. This subtle shift marks the beginning of autumn, where the days gradually shorten, leading us towards the shorter daylight hours of October and November, which both feature just 11 hours. Notably, this pattern reflects a consistent trend throughout the year: daylight peaks during the summer months, from May to July, with a notable high of 14 hours, before gradually dimming as winter approaches. The rhythmic change in daylight not only influences the natural environment but also invites residents and visitors alike to appreciate the beauty of Mendocino under varying shades of light throughout the seasons.
As September unfolds in Mendocino, the winds begin to settle, with an average speed of 2.7 m/s (6 mph), marking a notable dip compared to the livelier gusts of summer. This decline follows a gradual peak in May at 5.0 m/s (11 mph), highlighting a trend where the steady breezes of the earlier months give way to more tranquil conditions as autumn approaches. The shift reflects not just a change in wind patterns but also invites a serene ambiance perfect for enjoying the stunning coastal views. In fact, September’s calmness sets the stage for the crisp, invigorating winds of October, which bring a refreshing resurgence at 3.5 m/s (8 mph). As the year transitions, each month tells a story of nature's rhythmic cycle, inviting both residents and visitors to relish the subtle beauty of Mendocino's coastal climate.
The weather in Mendocino 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 Mendocino and find detailed weather information for every month.
September and January present strikingly different weather patterns. September boasts a wider temperature range, with minimums reaching 8°C (47°F) and daytime highs soaring to 36°C (96°F), accompanied by relatively low precipitation of just 6 mm (0.2 in) over one day. In contrast, January experiences much cooler temperatures, with averages around 10°C (50°F) and a significant maximum of 21°C (69°F). The winter month is marked by considerably higher precipitation at 147 mm (5.8 in) spread over 11 days, along with elevated humidity levels at 86%. For further details on January weather in Mendocino, visit Mendocino weather in January.
When comparing the weather in September and February, there is a notable contrast in temperature and precipitation levels. September boasts a wider temperature range with a minimum of 8°C (47°F) and a maximum of 36°C (96°F), resulting in an average of 18°C (64°F). In contrast, February experiences much cooler temperatures, with a minimum of 0°C (32°F) and a maximum of 24°C (76°F), averaging just 10°C (50°F). Precipitation is significantly higher in February, receiving 137 mm (5.4 in) over 11 days compared to a mere 6 mm (0.2 in) of rain spread across only 1 day in September. Additionally, February's higher humidity at 84% surpasses September's 68%, making the winter month feel much wetter. For more details, you can check Mendocino weather in February.
September tends to be warmer and drier compared to March. The average temperature in September is significantly higher at 18°C (64°F), with maximums reaching up to 36°C (96°F), while March averages only 10°C (51°F) and peaks at 23°C (74°F). Additionally, September experiences minimal precipitation, averaging just 6 mm (0.2 in) over one day, contrasting sharply with March’s higher rainfall of 108 mm (4.2 in) spread across 13 days. Humidity levels are also higher in March at 83%, compared to 68% in September, making March feel more damp and cool. For more details on the specifics of March weather, see Mendocino weather in March.
When comparing the weather in September and April, one can observe distinct differences in temperature and precipitation. September tends to be warmer, with average temperatures ranging from a cool 8°C (47°F) to a sizzling max of 36°C (96°F), along with relatively low precipitation of only 6 mm (0.2 in) spread over just 1 day. In contrast, April experiences cooler temperatures, averaging between 4°C (39°F) and a maximum of 23°C (74°F), accompanied by significantly higher rainfall of 60 mm (2.4 in) over 7 days, indicative of a wetter season. Additionally, April's humidity levels are slightly higher, averaging around 80%, compared to September's 68%. For more detailed information, you can check out Mendocino weather in April.
When comparing the weather in September and May, several notable differences emerge. September usually boasts warmer temperatures, with average highs reaching up to 36°C (96°F), while May's temperatures peak at a milder 26°C (79°F). Although September has a higher average temperature, it experiences significantly less precipitation, averaging only 6 mm (0.2 in) over 1 day, compared to May's 43 mm (1.7 in) over 4 days. Additionally, May tends to be more humid, with humidity levels around 80%, compared to September's 68%. For more information, you can check the Mendocino weather in May.
In September, the weather tends to be a bit warmer than in June, with maximum temperatures reaching up to 36°C (96°F) compared to June's maximum of 31°C (88°F). However, June boasts a slightly cooler average temperature of 16°C (62°F) versus September's 18°C (64°F). Precipitation levels are minimal in both months, with September experiencing only 6 mm (0.2 in) over just one day, while June sees even less rain at 2 mm (0.1 in) with no rainy days. Additionally, humidity is higher in June at 76% compared to September's 68%. For a detailed look at June's climate, visit Mendocino weather in June.
In comparing the weather between September and July, September presents a broader range of temperatures, with a minimum of 8°C (47°F) and a maximum that can soar to 36°C (96°F), leading to an average temperature of 18°C (64°F). This month experiences slightly more precipitation, with 6 mm (0.2 in) falling over just one day, and maintains a humidity level of 68%. In contrast, July has a milder temperature range, with a minimum of 11°C (52°F) and a maximum of 29°C (84°F), resulting in an average of 17°C (63°F). July is also drier, recording only 2 mm (0.1 in) of precipitation over no rainy days and a humidity level of 70%. For those interested in more specific details, check out Mendocino weather in July.
In comparing the weather of September and August, we see some notable differences. September features a wider temperature range, with minimums dropping to 8°C (47°F) and maximums soaring to 36°C (96°F), while August remains milder with minimums at 11°C (51°F) and maximums capping at 31°C (88°F). Despite both months sharing an average temperature of 18°C (64°F), September is marked by slightly higher humidity at 68%, compared to August's 66%. Precipitation levels also vary, with September receiving 6 mm (0.2 in) of rain over one day, while August enjoyed a dry month with only 1 mm (0.0 in) of rain and no rainy days. For more insight into August conditions, you can check Mendocino weather in August.
In comparing the weather between September and October, it's clear that October brings cooler temperatures and increased precipitation. September showcases a wider temperature range, with minimums around 8°C (47°F) and maximums soaring up to 36°C (96°F), while the average temperature sits at 18°C (64°F). In contrast, October's temperatures dip slightly, featuring a minimum of 6°C (43°F) and a maximum of 32°C (90°F), with an average of 15°C (60°F). Additionally, October experiences a notable increase in rainfall, with 43 mm (1.7 in) over three days compared to September's meager 6 mm (0.2 in) over just one day. Humidity levels also rise marginally, from 68% in September to 72% in October. For a detailed look at October weather, you can visit Mendocino weather in October.
In September, the weather typically features a wide temperature range with minimums around 8°C (47°F) and maximums reaching up to 36°C (96°F), making it considerably warmer overall, with an average temperature of 18°C (64°F). The month sees minimal precipitation, with only about 6 mm (0.2 in) falling over just one day, and humidity levels are relatively moderate at 68%. In contrast, November experiences a significant drop in temperatures, with minimums dipping to 1°C (35°F) and an average of 12°C (53°F), peaking at a much milder 22°C (72°F). Precipitation rises dramatically to 72 mm (2.8 in) over six days, and humidity increases to 84%, creating a much wetter and cooler environment. For more detailed insights into November's climate, you can check Mendocino weather in November.
September weather is characterized by a warm range of temperatures, with minimums around 8°C (47°F) and maximums peaking at 36°C (96°F), while maintaining an average of 18°C (64°F). The month sees minimal precipitation, with only 6 mm (0.2 in) over just 1 day and relatively moderate humidity levels at 68%. In contrast, December brings much cooler weather, with temperatures dropping to a minimum of 2°C (35°F) and averaging around 10°C (50°F). The maximum temperature in December reaches only 20°C (68°F), but the month experiences significantly higher precipitation at 97 mm (3.8 in) over 11 days, coupled with increased humidity at 84%. For more details, you can check Mendocino weather in December.
As summer draws to a close, September in Mendocino brings a delightful shift in weather, offering a perfect blend of warm days and cool nights. Unlike the peak heat of July and August, temperatures gradually stabilize, providing an average warmth that's more comfortable for outdoor activities. With only minimal rainfall and just a single day of precipitation, the month is predominantly sunny, making it an ideal time to explore the breathtaking coastal scenery. Humidity remains moderate, creating a pleasant atmosphere that contrasts with the drier months ahead. For a deeper dive into Mendocino's climate patterns, be sure to check out Mendocino Climate.