Last updated: February 24, 2025
Experience September in Berkeley, United States, where the weather delights with pleasantly warm temperatures. The month showcases a maximum high of 40°C (104°F), contrasted by a comfortable average of 19°C (66°F) and a minimum low of 8°C (48°F). With zero precipitation days and only 1 mm (0.0 in) of rainfall recorded, this period promises sunny skies and dry conditions, complemented by a 55% humidity level that enhances the overall comfort. Perfect for outdoor activities, September in Berkeley is a brilliant time to enjoy the region's vibrant atmosphere.
As summer transitions to fall, Berkeley's temperatures in September showcase a warm yet pleasant climate. The month begins with minimums around 8°C (48°F), steadily rising to an average temperature of 19°C (66°F), making it a comfortable time for outdoor activities. However, the days can sizzle, peaking at a maximum of 40°C (104°F), highlighting a notable warmth compared to the cooler months preceding it. This trend signifies a gradual decline from the intense heat of August, where maximums hit an identical high, suggesting September is often a final, sultry stretch before the cooler October breezes make their entrance. Overall, it's a month where the warmth lingers just long enough to enjoy the last vestiges of summer.
In September, Berkeley experiences a significant drop in precipitation, with just 1 mm (0.0 in) recorded and no rainy days to speak of. This marks a continuation of the dry spell that typically begins in late summer, following two months of absolute dryness in July and August. As the region transitions into the fall, the minimal rainfall is a precursor to the upcoming months when precipitation begins to gradually increase, signaling a shift back to wetter weather. Compared to earlier months, September serves as a bridge that highlights the contrast between the dry summer and the wet winter, with the promise of an october increase looming just ahead.
In September, Berkeley experiences a slight uptick in humidity, averaging 55%, which reflects a gradual transition from the drier summer months. The trend throughout the year showcases a notable decrease in humidity from January's peak at 82% to a summer low of 54% in August. This consistency in declining moisture levels highlights the region's arid summer climate. As September rolls in, the increase from August is modest but foreshadows the return of a more humid atmosphere in the fall. With October bringing the humidity back up to 62%, it's clear that the shift towards the wetter months is just beginning, setting the stage for the lush scenery that characterizes the later part of the year.
In Berkeley, September brings a UV Index of 9, which falls into the very high exposure category. As summer transitions to fall, the UV levels remain significant, comparable to the peak readings of July and August. During this month, residents and visitors alike should take heed, as staying in the sun for more than 15 minutes can lead to sunburn. This trend underscores the importance of sun safety in the early autumn months. As temperatures gradually cool off, it is crucial to remain vigilant about UV exposure. For more detailed insights and daily updates, check out Berkeley UV Index.
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As September arrives in Berkeley, the city basks in 299 hours of sunshine, a delightful mix of warmth and clarity before the cooler months settle in. This month follows a vibrant summer, where June and July saw a peak of 355 and 349 hours, respectively. August, while still bright with 320 hours, begins the gentle decline towards autumn. September retains a comfortable brightness, yet hints at the approaching seasonal change, giving residents and visitors alike the perfect opportunity to enjoy the lingering outdoor activities. The steady drop in sunlight from the high of June serves as a reminder of nature’s rhythm, heralding a cozy transition into October's 276 hours, while still allowing for those golden afternoons that Berkeley is cherished for.
As summer transitions to autumn, Berkeley experiences a shift in sunshine probabilities, with September boasting a solid 60% chance of sunny weather. This month maintains a favorable outlook, closely mirroring the sunnier months of June (62%) and August (61%). Following the mostly bright days of summer, this September essentially captures the tail end of sunny season, allowing residents and visitors to enjoy pleasant outdoor activities before the cooler months arrive. The likelihood of clear skies remains higher compared to the fall months ahead, making September an ideal time to relish Berkeley's vibrant landscapes bathed in sunlight.
As summer transitions into autumn, September in Berkeley sees a gentle decline in daylight hours, averaging 12 hours of light per day. This month marks a shift from the peak of 14 hours witnessed in June and July, as daylight gradually wanes. With August’s lingering warmth, the days still hold a generous amount of sunshine, but as September progresses, the sun sets a bit earlier, hinting at the cooler months ahead. This trend reflects the natural rhythm of the seasons, where longer days of summer make way for the cozy embrace of fall, fostering an appreciation for the changing light and the vibrancy it brings to the Bay Area.
As September rolls in, Berkeley experiences a gentle breeze with an average wind speed of 2.6 m/s (6 mph), marking a notable decline from the summer months. May sees the peak winds at 3.9 m/s (9 mph), gradually tapering off as the seasons change. The wind in June and July holds steady at 3.4 m/s (8 mph), but by September, we find ourselves enjoying a softer, more tranquil atmosphere as the gusts become milder. This gentle wind continues into October, maintaining an average of 2.8 m/s (6 mph) before settling into a quieter November with just 1.9 m/s (4 mph). Overall, the trend showcases a clear transition from the lively winds of summer to the calmer breezes of fall, inviting residents and visitors alike to savor the peacefulness of early autumn in this vibrant city.
The weather in Berkeley 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 Berkeley and find detailed weather information for every month.
September and January present stark contrasts in weather conditions. In September, temperatures range from a minimum of 8°C (48°F) to a scorching maximum of 40°C (104°F), with an average of 19°C (66°F) and virtually no precipitation. The humidity stands at 55%, creating a warm but generally dry atmosphere. In contrast, January experiences much cooler temperatures, with a minimum of 0°C (32°F) and a comfortable maximum of 25°C (78°F), averaging around 10°C (51°F). This month is significantly wetter, with 94 mm (3.7 in) of precipitation spread over 8 days and a higher humidity level of 82%. For more information on January weather, you can visit Berkeley weather in January.
September and February present contrasting weather conditions. In September, temperatures range from a cool 8°C (48°F) at night to a sweltering maximum of 40°C (104°F) during the day, with an average of 19°C (66°F). This month is characterized by minimal precipitation, with only 1 mm recorded over virtually no rainy days, leading to a moderate humidity level of 55%.
In contrast, February sees significantly cooler temperatures, with a minimum of 1°C (34°F) and a maximum of 26°C (78°F), averaging 11°C (53°F). This month experiences substantial rainfall, totaling 91 mm over about 8 rainy days, contributing to a higher humidity at 84%. For a more detailed look at the weather patterns during this time, you can check Berkeley weather in February.
The weather in September is characterized by warm temperatures, ranging from a minimum of 8°C (48°F) to a scorching maximum of 40°C (104°F), with an average temperature of 19°C (66°F). In contrast, March features cooler conditions, with temperatures ranging from a minimum of 3°C (37°F) to a maximum of 27°C (81°F) and an average temperature of 12°C (54°F). While September enjoys very little precipitation at just 1 mm over the month and zero rainy days, March experiences significantly higher precipitation at 73 mm, occurring over 10 days, resulting in much higher humidity levels of 82% compared to September's 55%. For more insights about the weather during this time, you can check out Berkeley weather in March.
September and April present strikingly different weather patterns. In September, temperatures range from a mild 8°C (48°F) at night to a scorching 40°C (104°F) during the day, with an average of 19°C (66°F) and virtually no rainfall. The humidity sits at a moderate 55%, creating a warm and dry atmosphere. In contrast, April features cooler temperatures, with nighttime lows of 4°C (40°F) and daytime highs reaching 31°C (88°F), leading to an average temperature of 14°C (58°F). This month also experiences more precipitation, with 29 mm (1.2 in) of rainfall over five days and higher humidity at 78%. For more details, check out Berkeley weather in April.
When comparing the weather in September and May, we see notable differences in temperature and humidity. September experiences warmer temperatures, with an average of 19°C (66°F) and a maximum reaching up to 40°C (104°F), while May's average temperature is cooler at 15°C (60°F), peaking at 32°C (90°F). In terms of precipitation, September is quite dry with only 1 mm and no rainy days, whereas May sees more moisture, accumulating 18 mm over two days. Additionally, the humidity levels are higher in May at 71%, compared to September's 55%, creating a more humid atmosphere. For a detailed look at the climate during this time, check out Berkeley weather in May.
In comparing the weather between September and June, September tends to be slightly warmer, with an average temperature of 19°C (66°F) compared to June's average of 18°C (64°F). September can also reach higher maximum temperatures, peaking at 40°C (104°F) versus June's maximum of 37°C (99°F). However, June experiences a bit more precipitation, averaging 2 mm (0.1 in) compared to September's minimal 1 mm (0.0 in), and it also has higher humidity levels at 64% compared to September's 55%. For a more detailed look at June weather, you can visit Berkeley weather in June.
When comparing the weather in September and July, September tends to offer a wider temperature range, with minimums as low as 8°C (48°F) and maximums reaching up to 40°C (104°F). In contrast, July's temperatures are milder, with lows around 11°C (53°F) and highs peaking at 32°C (90°F). Both months experience minimal precipitation, with September receiving only 1 mm of rain and July having no recorded precipitation. Additionally, humidity levels are fairly similar, with September at 55% and July slightly higher at 58%. For more detailed insights, you can check Berkeley weather in July.
In comparing the weather of September and August, we can observe some notable differences. September generally experiences a wider temperature range, with minimums dropping to 8°C (48°F) and maximums reaching a scorching 40°C (104°F), compared to August, which has minimums around 11°C (52°F) and maximums peaking at 37°C (99°F). Both months see very little precipitation, with September receiving just 1 mm and August recording none at all. Humidity levels remain similar, with September at 55% and August slightly lower at 54%. For more detailed information, you can check Berkeley weather in August.
September features a warm climate with a minimum temperature of 8°C (48°F) and an average of 19°C (66°F), peaking at a sweltering 40°C (104°F). The month is dry, receiving only 1 mm of precipitation over no rainy days, and maintaining a humidity level of 55%. In contrast, October brings cooler conditions, with a lower minimum temperature of 5°C (41°F) and an average of 17°C (63°F), while the maximum temperature drops to 34°C (93°F). October is also wetter, recording 24 mm of precipitation over just one rainy day, along with a slight increase in humidity to 62%. For more detailed information about the weather in this month, you can visit Berkeley weather in October.
September and November weather exhibit notable differences in temperature and precipitation patterns. September typically experiences warmer days, with average temperatures around 19°C (66°F) and maximums soaring up to 40°C (104°F), while November cools down significantly, averaging only 13°C (56°F) and peaking at 27°C (81°F). Furthermore, September enjoys dry conditions with minimal precipitation and no rainy days, whereas November sees an increase in moisture, with about 42 mm (1.7 inches) of rain over five days and higher humidity levels at 78%. For a closer look at November weather specifics, you can check out Berkeley weather in November.
September and December showcase a stark contrast in weather patterns. In September, temperatures range from a minimum of 8°C (48°F) to a scorching maximum of 40°C (104°F), with an average temperature of 19°C (66°F) and no recorded precipitation. The humidity stands at a moderate 55%, making for relatively dry conditions. In contrast, December experiences a cooler climate, with temperatures ranging from a minimum of 2°C (35°F) to a maximum of 23°C (74°F) and an average of just 10°C (51°F). December is characterized by significantly higher precipitation, totalling 80 mm (3.2 in) over eight days, and humidity levels rise to 80%, adding to the overall dampness of the season. For more information, check out Berkeley weather in December.
As summer gives way to autumn, September in Berkeley stands out with its warm and pleasant climate. With average temperatures hovering around the comfortable 19°C (66°F) and minimal to no precipitation, the month boasts a dry charm that sets it apart from the rainier seasons ahead. This low humidity level, averaging 55%, contributes to the delightful weather, making it an ideal time for outdoor activities and exploring the beautiful landscapes. Unlike the cooler months that follow, September offers a perfect blend of warmth without the sweltering heat, allowing residents and visitors alike to relish in the mild, sun-kissed days. To further explore the distinct characteristics of Berkeley's climate throughout the year, check out Berkeley Climate.