Last updated: February 24, 2025
August in San Francisco presents a delightful climate, characterized by a maximum temperature of 27°C (81°F), allowing for warm summer days. The average temperature hovers around 16°C (61°F), providing a comfortable experience, while the nights cool down to a minimum of 11°C (53°F). Notably, this month sees an almost rain-free environment with only 2 mm (0.1 in) of precipitation, showcasing 0 rainy days. Despite the warm days, an 87% humidity level adds a touch of moisture to the otherwise sunny weather, making it ideal for outdoor activities and sightseeing in this vibrant city.
In August, San Francisco enjoys a delightful transition into late summer, characterized by mild temperatures that make the city particularly inviting. With minimums around 11°C (53°F) and an average of 16°C (61°F), the weather is comfortably warm, providing a perfect backdrop for outdoor activities. The maximum temperature peaks at about 27°C (81°F), making it one of the hotter months of the year but still significantly cooler compared to other regions in the U.S. This trend of gradual warmth follows the cooler, foggy summer months of June and July, shifting from the coastal chills to a more temperate climate that lures both locals and tourists alike. With such inviting conditions, August stands out as a prime time to experience the vibrant culture and stunning landscapes of San Francisco.
In August, San Francisco experiences a notable dry spell, receiving a mere 2 mm (0.1 in) of precipitation, with no recorded rainfall days. This pattern reflects the city's typical summer climate, characterized by warm, arid conditions and an extended absence of rain. As the summer months progress, precipitation gradually diminishes from the earlier spring levels, peaking in winter and then sharply declining by August. This dryness sets the stage for the cooler, wetter months ahead, making the brief yet vibrant summer season all the more cherished.
August in San Francisco brings a hint of summer stickiness, with humidity levels peaking at 87%, matching the high of July. This period marks the culmination of a gradual rise in humidity that starts in early spring and reaches its zenith during the warmest months. As residents bask in the late-summer sunshine, they also contend with an atmosphere that feels noticeably heavier. Following August, a slight dip to 86% humidity in September signals the beginning of a gradual transition into the milder, drier conditions of autumn. Overall, the summer months showcase a distinctive trend of heightened humidity, creating a unique sensation that characterizes San Francisco's coastal climate.
In August, San Francisco experiences a UV Index of 10, categorized as very high, signaling that sun exposure requires caution. This marks a slight decline from the extreme levels recorded in both June and July, where the UV Index peaked at 11. The burn time for unprotected skin in August is approximately 15 minutes, mirroring the conditions prevalent in March through September, indicating a trend of significant sun intensity as summer reaches its height. It's essential to remain vigilant during this month, as UV radiation remains potent, especially in the late summer sun. For more detailed information, visit the complete San Francisco UV Index.
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August in San Francisco typically showcases a delightful mix of warmth and vibrant sunshine, contributing to 320 hours of bright daylight—significantly lower than the peak June hours but still radiant enough to attract locals and visitors alike. Following the sunny high of 355 hours in June, August reflects a gradual transition towards autumn, though it remains a favorite for outdoor activities. As the summer months wane from July’s 349 hours, this period serves as a gentle reminder of the impending coolness, yet still offers a satisfying abundance of sunshine that keeps the city's spirit lively and bright. With September trailing closely at 299 hours, the warm glow of August lingers, allowing San Francisco to bid farewell to summer in style.
In August, San Francisco experiences a 47% chance of sunny weather, a slight uptick from the previous month’s 37% in July. This moderate likelihood continues the trend of fluctuating sunshine throughout the summer months, where May stands out with the highest chance of sun at 66%. While August may not deliver the most sun of the year, it sits comfortably in the middle range, offering a blend of fog and sunshine. As summer transitions into fall, September brings a touch more sunshine at 51%, reflecting San Francisco's unique climatological patterns. Overall, August serves as a reminder of the city's ever-changing weather, where sunny days can be both rare and cherished.
In August, San Francisco basks in approximately 13 hours of daylight, a slight decrease from the peak summer months of June and July, which enjoy a maximum of 14 hours. This gradual shift signals the transition towards fall, as daylight hours steadily decline from the summer solstice. The city’s daylight duration begins at just 9 hours in January, steadily increasing through the spring and summer months, reflecting the seasonal rhythm of light. By August, the golden sunshine begins to wane, hinting at shorter days ahead, yet the lingering warmth still offers plenty of time to enjoy the outdoors before the evenings begin to draw in.
In San Francisco, the month of August greets residents and visitors with a mild average wind speed of 3.7 m/s (8 mph), a slight dip from the spring and summer peak reached in May when the winds were at their strongest at 5.4 m/s (12 mph). As the summer progresses, the winds tend to calm down, reflecting a broader trend where speed generally fluctuates throughout the year. Typically, winds start strong in early spring, peak slightly in late spring, and then gradually decrease toward late summer and into fall. September follows closely with a similar speed of 3.3 m/s (7 mph), indicating a continued easing as the city transitions into the cooler autumn months. Overall, August showcases a balance, maintaining breezy comforts while hinting at the seasonal shift ahead.
The weather in San Francisco changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of August's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in San Francisco and find detailed weather information for every month.
The weather in August and January presents a striking contrast in San Francisco. August enjoys milder temperatures, ranging from a minimum of 11°C (53°F) to a maximum of 27°C (81°F), with low precipitation of just 2 mm and virtually no rainy days. In contrast, January is cooler, with temperatures dipping as low as 3°C (38°F) and only reaching a maximum of 21°C (70°F). Additionally, January experiences significantly higher precipitation, averaging 106 mm over 9 days. Despite the increased rain, humidity levels remain relatively similar between the two months, at 87% in August and 85% in January. For more detailed information about January weather, visit San Francisco weather in January.
August and February showcase contrasting weather patterns. In August, temperatures range from a minimum of 11°C (53°F) to a maximum of 27°C (81°F), with an average of 16°C (61°F) and virtually no precipitation, highlighting a dry and humid atmosphere with 87% humidity. In contrast, February presents cooler temperatures, characterized by a low of 4°C (39°F) and a high of 20°C (69°F), resulting in an average of 11°C (52°F). This month is significantly wetter, with 109 mm (4.3 inches) of precipitation over 9 days, coupled with a slightly lower humidity at 82%. For more detailed information, you can check San Francisco weather in February.
When comparing the weather in August and March, significant differences emerge. August boasts warmer temperatures, with a minimum of 11°C (53°F) and an average of 16°C (61°F), peaking at 27°C (81°F). In contrast, March is cooler, featuring a minimum of 5°C (42°F) and an average of 12°C (53°F), with a maximum of 20°C (69°F). Additionally, August experiences very little precipitation, averaging only 2 mm (0.1 in) over a completely dry month, whereas March is considerably wetter, receiving around 78 mm (3.1 in) of rain across approximately 10 days. Despite the warmer temperatures in August, humidity remains relatively high at 87%, while it is slightly lower in March at 82%. For more detailed information, you can visit San Francisco weather in March.
In August, the weather is generally warmer and drier compared to April, with average temperatures ranging from a minimum of 11°C (53°F) to a maximum of 27°C (81°F) and just 2 mm of precipitation over the entire month. Conversely, April sees lower average temperatures, with a minimum of 7°C (44°F) and a maximum of 28°C (82°F), along with significantly higher precipitation totaling 35 mm (1.4 in) over about 5 rainy days. Additionally, April experiences a slightly lower humidity level of 79% compared to the high humidity of 87% in August. For more details, you can check out San Francisco weather in April.
In San Francisco, August typically boasts warmer temperatures compared to May, with averages of 16°C (61°F) in August versus 14°C (57°F) in May. August experiences a maximum temperature of 27°C (81°F), while May peaks at a more moderate 24°C (75°F). Additionally, August is notably drier, with only 2 mm (0.1 in) of precipitation recorded over zero rainy days, compared to May's 20 mm (0.8 in) spread over two days. Humidity levels are similar, with August at 87% and May at 83%. For more detailed weather insights, check out San Francisco weather in May.
When comparing the weather in August and June, both months exhibit mild temperatures, but August tends to be slightly warmer overall. In June, the average temperature is about 15°C (60°F) with a maximum of 31°C (88°F), while August averages around 16°C (61°F) with a maximum of 27°C (81°F). Precipitation levels are low in both months, with June receiving 3 mm (0.1 in) and August just 2 mm (0.1 in), and neither month seeing any rainy days. Humidity levels are also similar, with August at 87% and June slightly lower at 84%. For more details on June weather, you can visit San Francisco weather in June.
In comparing the weather between July and August, August tends to be warmer, with average temperatures rising from 15°C (60°F) in July to 16°C (61°F) in August. The maximum temperature also increases, reaching 27°C (81°F) in August compared to July's maximum of 24°C (76°F). Both months experience similar low temperature averages, with minimal precipitation recorded, just 2 mm in August and 3 mm in July, both with 0 days of rain. Humidity remains consistent at 87% for both months. For more in-depth information, you can check out San Francisco weather in July.
In August, the weather features mild temperatures with a minimum of 11°C (53°F), an average of 16°C (61°F), and a maximum of 27°C (81°F). The month is characterized by low precipitation, with no rainy days, and a relatively high humidity of 87%. In contrast, September presents a slightly warmer climate, maintaining the same minimum of 11°C (51°F) but offering a higher average of 17°C (63°F) and a striking maximum of 35°C (96°F). Similar to August, September also experiences minimal precipitation, amounting to just 2 mm (0.1 in) over zero rainy days, and slightly lower humidity at 86%. For a more detailed insight into the specifics of September's climate, visit San Francisco weather in September.
August and October exhibit distinct weather characteristics. In August, temperatures range from a minimum of 11°C (53°F) to a maximum of 27°C (81°F), with an average of 16°C (61°F). The month boasts little to no precipitation, recording just 2 mm (0.1 in) and maintaining high humidity levels at 87%. In contrast, October experiences slightly cooler temperatures, with a minimum of 9°C (48°F) and a maximum of 28°C (84°F), while the average temperature remains the same at 16°C (60°F). However, October is noticeably wetter, receiving 30 mm (1.2 in) of precipitation over two days and a decrease in humidity to 80%. For more detailed insights, check out San Francisco weather in October.
In August, the weather tends to be warmer and more stable, with average temperatures ranging from a minimum of 11°C (53°F) to a maximum of 27°C (81°F) and only 2 mm of precipitation over the month. The humidity is quite high at 87%, creating a muggy atmosphere, but it remains dry with no rainy days. Conversely, November sees cooler temperatures, with an average ranging from 6°C (43°F) to a maximum of 23°C (74°F). This month experiences significantly more precipitation, totaling 50 mm (2.0 inches) over five rainy days, and the humidity decreases slightly to 79%. For a more detailed look at November weather specifics, refer to San Francisco weather in November.
In August, the weather is generally warmer and drier, with average temperatures ranging from a minimum of 11°C (53°F) to a maximum of 27°C (81°F) and only 2 mm (0.1 in) of precipitation. The humidity is notably high at 87%, creating a warm and muggy atmosphere. In contrast, December experiences cooler temperatures, with an average ranging from a minimum of 4°C (40°F) to a maximum of 20°C (69°F). This month is significantly wetter, recording 95 mm (3.7 in) of precipitation over 9 days, and the humidity is slightly lower at 79%. For a more detailed look at the weather patterns during this month, check out San Francisco weather in December.
August in San Francisco is a remarkable contrast to the cooler, foggier months earlier in the year. With warm maximum temperatures and an average that hovers pleasantly around 16°C, it’s a time when residents can truly relish the sunshine without frequent interruptions from rain—just 2 mm of precipitation recorded, and not a single rainy day! The high humidity at 87% adds a touch of tropical warmth but does little to dampen the festive atmosphere of the city. For those seeking to understand the broader patterns of San Francisco's climate, exploring the unique charm of August is essential. Discover more at San Francisco Climate.