Last updated: February 24, 2025
In August, Yosemite Valley experiences a delightful array of summer weather, with daily maximum temperatures reaching 29°C (84°F) and an average temperature of 16°C (62°F). Nights can be cool, dipping to a minimum of 4°C (39°F), offering a refreshing contrast to the daytime warmth. While the total precipitation is modest at 17 mm (0.7 in) over 5 days, visitors should still be prepared for the occasional brief shower. With humidity levels around 30%, the air remains comfortably dry, making it an ideal time for outdoor adventures amidst the stunning natural beauty of the valley.
In Yosemite Valley, August marks the peak of summer warmth, with temperatures showcasing a notable rise from earlier months. The minimum temperature settles at a relatively mild 4°C (39°F), while daytime averages hover around 16°C (62°F), and the mercury can reach up to 29°C (84°F). Compared to the winter months, where temperatures plunge below freezing, August stands out as a period of comfortable weather, perfect for hiking and exploring the breathtaking landscapes. As the season transitions into September, a slight dip in temperatures begins, yet August remains a vibrant month, inviting visitors to soak in the natural beauty under the warm sun.
In Yosemite Valley, August marks the tail end of a drier season, with precipitation levels dropping to just 17 mm (0.7 in) over approximately five days of rain. This is noticeably lower than the earlier months, especially when compared to the heavier snowfall in January and February, which regularly saw over 220 mm of rain. The decreasing trend in moisture from late spring through summer becomes clear, as May's 68 mm (2.7 in) gives way to June and July's minimal rainfall. As the valley basks in summer's warmth, the brief August showers are a gentle reminder of the changing seasons ahead, setting the stage for the more robust rainfall that typically arrives in the fall.
In Yosemite Valley, August stands out as the driest month of the year, with humidity levels dipping to a mere 30%. This significant decrease follows a pattern of declining moisture that begins in June, where the humidity is already low at 49%. The transition from the lush, humid winter months—characterized by levels around 82% in January—into the summer reveals a seasonal rhythm that highlights the valley's dynamic climate. As the year progresses, Yosemite experiences a notable drop in humidity, peaking in the winter and transitioning to a much drier atmosphere by late summer. This trend not only affects the local ecosystem but also shapes the visitor experience, offering a unique blend of beauty wrapped in the crisp, clear summer air.
As summer transitions towards fall in Yosemite Valley, the UV Index in August remains at a notable 11, classifying it in the extreme exposure category with a burn time of just 10 minutes. This trend of high UV levels peaks from May through July, displaying a consistent pattern of elevated exposure that begins to taper off in early autumn. While August's UV Index drops slightly from July's peak of 12, it's essential for visitors to stay vigilant about sun protection during their outdoor activities, particularly as days remain long and sunny. To learn more about the UV Index throughout the year, explore Yosemite Valley UV Index.
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In August, Yosemite Valley basks in a generous 364 hours of sunshine, contributing to its stunning summer beauty and vibrant outdoor activities. This month stands as a remarkable highlight in the seasonal sunshine spectrum, following the peak of July’s 392 hours, while remaining above the notable totals of earlier months. From the year’s start, there's a clear upward trend from a mere 170 hours in January, showcasing the gradual transition from winter's chill to summer's warmth. As autumn approaches with September's 323 hours, August is a delightful reminder of the abundance of light that graces this iconic landscape, inviting visitors to fully embrace its natural splendor.
In August, Yosemite Valley basks in the sunshine with an impressive 92% chance of clear skies, making it one of the most sun-kissed months of the year. This peak in sunny weather follows a steady ascent from the previous months; as spring transitions into summer, the probability of sun climbs from 69% in April to 81% in June. July maintains a robust 72% chance, but by August, visitors can fully embrace the warmth and beauty of the valley. Following August, the likelihood of sunny days begins to taper off slightly, yet September still offers an inviting 89% chance for outdoor adventures. Overall, August stands out as a prime month for enjoying the breathtaking landscapes bathed in summer sunlight.
As summer wanes in Yosemite Valley, August offers a delightful ~13 hours of daylight, gradually transitioning from the peak of June, July, and early August's 14-hour days. The daylight duration reflects a subtle yet noticeable decline, hinting at the impending arrival of autumn. This diminishing light not only enhances the stunning hues of the valley as daylight fades but also signals a time of change, as nature prepares for cooler months ahead. Following the vibrant days of summer, the descent into September's 12 hours marks the start of a gradual retreat into shorter, crisper days, painting a beautiful picture of the cyclical rhythm of the seasons.
In August, the average wind speed in Yosemite Valley settles at a gentle 2.0 m/s (5 mph), mirroring the consistent breezes felt during earlier summer months. This slight dip from July's 1.8 m/s maintains a pleasant atmosphere, perfect for exploring the valley’s breathtaking landscapes. As the summer transitions to fall, the winds generally stabilize, with speeds holding steady at 2.0 m/s through September and October. Interestingly, the year wraps up with a slight uptick to 2.2 m/s (5 mph) in December, hinting at a refreshing vigor in the air. Overall, the wind patterns reveal a comforting consistency throughout the year, enhancing Yosemite's serene beauty and inviting visitors to embrace its natural wonders.
The weather in Yosemite Valley 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 Yosemite Valley and find detailed weather information for every month.
In August, the weather is notably warmer with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 29°C (84°F), accompanied by low precipitation levels of 17 mm (0.7 in) spread over 5 days and a humidity of 30%. In contrast, January brings much colder conditions, with temperatures ranging from a minimum of -18°C (0°F) to a maximum of 11°C (51°F). The month experiences significantly higher precipitation of 227 mm (9.0 in) over 9 days, and the humidity increases dramatically to 82%. For a more detailed look at the weather conditions, you can check Yosemite Valley weather in January.
The weather in August contrasts sharply with that of February, presenting a vivid seasonal shift. In August, temperatures range from a mild 4°C (39°F) at night to a warm 29°C (84°F) during the day, with relatively low humidity at 30% and only 17 mm (0.7 in) of precipitation spread over 5 days. In contrast, February experiences far colder conditions with temperatures dropping as low as -21°C (-5°F) and averaging around -3°C (27°F), coupled with significantly higher precipitation of 226 mm (8.9 in) across 11 days, resulting in a humidity level of 85%. This stark difference highlights the dramatic climate changes between summer and winter months in Yosemite Valley. For more details on February weather in Yosemite, you can visit Yosemite Valley weather in February.
When comparing the weather in August and March, it’s clear that they present vastly different climates. August boasts a more temperate range, with temperatures spanning from a chilly 4°C (39°F) at night to a warm 29°C (84°F) during the day, accompanied by relatively low humidity at 30%. Precipitation is minimal, averaging just 17 mm (0.7 in) over about 5 days. In contrast, March experiences significantly colder temperatures, with nighttime lows plunging to -17°C (1°F) and daily highs only reaching up to 13°C (56°F). Additionally, March is notably wetter, with an average precipitation of 209 mm (8.2 in) spread over 13 days and high humidity levels at 80%. For a more detailed look at March weather, you can check Yosemite Valley weather in March.
When comparing the weather in August and April, it is clear that August offers a much warmer climate. The average temperature in August reaches a comfortable 16°C (62°F), with maximums soaring to 29°C (84°F), while April averages only 2°C (36°F) and can dip as low as -18°C (0°F). Additionally, August experiences significantly lower precipitation, with only 17 mm (0.7 in) over 5 days, compared to April’s substantial 102 mm (4.0 in) over 8 days. The humidity is also markedly different, with April reaching 72% compared to August’s drier 30%. For more details on April's weather patterns, you can visit Yosemite Valley weather in April.
The weather in August presents a notably warmer picture compared to May, with average temperatures ranging from a minimum of 4°C (39°F) up to a pleasant maximum of 29°C (84°F), while May experiences cooler conditions with temperatures varying from -13°C (9°F) to a maximum of 24°C (75°F). Additionally, August sees significantly less precipitation, totaling only 17 mm over 5 days, in contrast to May's wetter climate, which records 68 mm across 11 days. Humidity levels also differ, with August maintaining a drier atmosphere at 30%, while May tends to be more humid at 58%. For a deeper dive into how these climates play out, check out Yosemite Valley weather in May.
In comparing the weather between June and August, August generally boasts warmer temperatures, with a minimum of 4°C (39°F) and an average of 16°C (62°F), peaking at 29°C (84°F). In contrast, June experiences cooler conditions, starting at a minimum of -5°C (24°F) and averaging 13°C (55°F), with a maximum of 27°C (81°F). While both months see similar precipitation levels, with August recording 17 mm (0.7 in) and June slightly higher at 20 mm (0.8 in), the humidity in June is notably higher at 49%, compared to August's 30%. For more detailed information on June weather, check out Yosemite Valley weather in June.
In comparing the weather of July and August, both months experience similar maximum temperatures, peaking at around 29°C (84°F to 85°F). However, July tends to be slightly cooler overall, with an average temperature of 17°C (63°F), compared to August's average of 16°C (62°F). Precipitation is more frequent in July, with 24 mm (0.9 in) over 6 days, while August sees less rain at only 17 mm (0.7 in) across 5 days. Additionally, humidity levels are higher in July at 36%, compared to August's 30%. For more detailed insights, you can refer to Yosemite Valley weather in July.
August and September present noticeable shifts in weather conditions. In August, temperatures range from a minimum of 4°C (39°F) to a maximum of 29°C (84°F), with an average of 16°C (62°F). The month experiences relatively low precipitation at 17 mm (0.7 in) over 5 days, accompanied by low humidity at 30%. In contrast, September sees a drop in the minimum temperature to -8°C (18°F) and a slight decrease in the average to 13°C (55°F), while the maximum remains similar at 28°C (83°F). Precipitation remains consistent at 17 mm (0.7 in) but occurs over just 4 days, and humidity rises to 42%, indicating a shift toward a cooler and seemingly more humid atmosphere. For more detailed information, you can check Yosemite Valley weather in September.
August and October present a striking contrast in weather patterns. August typically experiences warmer temperatures, with a range from a minimum of 4°C (39°F) to a maximum of 29°C (84°F), while October sees cooler conditions, with temperatures ranging from -10°C (15°F) to a high of 24°C (75°F). Precipitation is less frequent in August, averaging only 17 mm (0.7 in) over 5 days, compared to October's higher precipitation levels of 43 mm (1.7 in) over just 3 days. Additionally, October is characterized by higher humidity at 59%, compared to August's relatively dry conditions with only 30% humidity. For more detailed information, check the Yosemite Valley weather in October.
August and November present starkly contrasting weather conditions. In August, temperatures range from a mild 4°C (39°F) at night to a warm 29°C (84°F) during the day, with an average of 16°C (62°F). The month sees relatively low precipitation, totaling just 17 mm (0.7 in) over 5 days, and the humidity is quite low at 30%. In contrast, November experiences much colder temperatures, with nighttime lows plunging to -20°C (-4°F) and daytime highs reaching up to 18°C (65°F), averaging around 2°C (36°F). Precipitation significantly increases to 98 mm (3.9 in) over 6 days, accompanied by a much higher humidity level of 78%. For more detailed information on this seasonal shift, check out Yosemite Valley weather in November.
The weather in August features much milder temperatures, with an average of 16°C (62°F), compared to the frigid December averages of -3°C (27°F). While August enjoys relatively low precipitation at 17 mm (0.7 in) over just 5 days, December sees a significant increase in rainfall, totaling 160 mm (6.3 in) over 10 days, along with much higher humidity levels at 79%. This stark contrast highlights how December can feel much more oppressive and wet, while August is generally warmer and drier. For more detailed insights into the colder months, visit Yosemite Valley weather in December.
As summer reaches its peak in Yosemite Valley, August offers a delightful contrast to the cooler months. Visitors can expect warm temperatures, with days averaging a comfortable 16°C (62°F), and peaks that soar up to 29°C (84°F). While precipitation remains relatively low, with only a handful of rainy days, the humidity is at a manageable 30%, allowing for pleasant outdoor adventures. This month stands out for its sunny days, making it ideal for exploring Yosemite's stunning landscapes. For a deeper dive into the nuances of Yosemite's climate throughout the year, check out Yosemite Valley Climate.