Last updated: February 24, 2025
In August, Washington, United States, experiences a vibrant mix of summer warmth and occasional rain. With a maximum temperature soaring to 37°C (99°F) and an average of 25°C (77°F), the month showcases the peak of summer heat, while cooler nights drop to a minimum of 14°C (58°F). This period also sees about 15 days of precipitation, accumulating to a total of 140 mm (5.5 in), giving the area a humidity level of 72%. Residents and visitors alike can expect a diverse climate that beautifully encapsulates the essence of summer in the Pacific Northwest.
In August, Washington embraces the height of summer, with temperatures reaching a maximum of 37°C (99°F). The month enjoys a comfortable average of 25°C (77°F) as the warm days bring residents outdoors. With evening lows at 14°C (58°F), warmth extends into the night, allowing for outdoor activities and social gatherings. This heat is a continuation of a gradual upward trend from earlier months, peaking after a trio of increasingly warm July days. As August draws to a close, the summer heat begins to ease, setting the stage for the cooler temperatures of Fall that follow in September.
In August, Washington experiences notable precipitation, receiving 140 mm (5.5 in) over an average of 15 days. This makes it one of the rainier months of the year, just slightly less than the much wetter July. Interestingly, while many other summer months see a gradual drop in rainfall, August maintains a significant moisture level, indicating a trend of late-summer showers. This sustained precipitation not only nourishes the lush landscapes but also prepares the terrain for the upcoming autumn months, where rain levels begin to stabilize and eventually decline. Overall, August stands out as a transitional period, showcasing the interplay between summer warmth and impending seasonal shifts.
In Washington, United States, August brings a noticeable drop in humidity, averaging 72%—the lowest level of the year. This decline follows a gradual decrease from spring through summer, with July peaking at 74% before the transition into the drier August air. Observing the annual trend, humidity remains high during the winter months, hovering around the mid-80% range, which contributes to the region's lush landscapes. As the year progresses into early fall, humidity begins to rise again in September, settling at 75%. Overall, August serves as a brief interlude of relief from the typically humid climate, setting the stage for the return of moisture as the seasons shift.
In August, Washington, D.C. experiences a UV Index of 9, categorizing the risk of harm from unprotected sun exposure as very high. As summer peaks, the burn time reduces to just 15 minutes, mirroring the intensity seen in the preceding months of June and July, which also boast a persistent UV Index of 10. This trend highlights the critical need for sun protection during this time, as both the natural warmth of the season and the heightened UV levels demand vigilance. As summer transitions into fall, the UV Index begins to gradually decline, signaling an opportunity to enjoy outdoor activities while still prioritizing skin safety. For more detailed insights on UV levels throughout the year, visit Washington UV Index.
UV Risk Categories
August in Washington, United States, shines with an impressive 321 hours of sunshine, making it a crown jewel in the summer months. This peak follows a gradual build-up from 150 hours in January to a dazzling 356 hours in July, illustrating the slow rise and warming embrace of summer. Although sunlight begins to wane in September to 277 hours, August remains a vibrant transition between the height of summer and the onset of fall. The overall trend showcases a clear seasonal progression, with longer days in the warmer months fostering an inviting atmosphere for outdoor activities. As the days shorten into autumn, the sunshine in August serves as a reminder of summer's lingering warmth before the cooler months emerge.
In Washington, August tends to be one of the less sunny months, with only a 34% chance of clear skies. Looking at the broader picture, this marks a dip compared to the summer peak in July, which enjoys a 49% chance of sunshine. Interestingly, as we transition from the warm months of June and July, which hold 38% and 49% chances of sun respectively, August falls behind, setting the stage for the slightly sunnier September at 53%. This trend underlines how summer's warmth gives way to early autumn's clearer days, painting a picture of fluctuating weather patterns that characterize Washington's yearly cycle. Despite the lower likelihood of sunny days in August, the anticipation of more sun in September serves as a reminder of the region's dynamic climate.
In August, Washington, United States, enjoys 13 hours of daylight, marking a subtle decline from the sun-drenched days of summer. This pattern reflects the natural progression of longer days that peak in June and July, offering residents a generous 14 hours of sunlight. As summer transitions into fall, daylight gradually retreated, but August still radiates warmth and extended evenings, inviting outdoor activities and late-night strolls. This month serves as a reminder of summer's lingering embrace before the shorter days of September and October take hold, highlighting a seasonal rhythm where the vibrant energy of long days begins to wane, transitioning into the cozy atmosphere of autumn.
As summer wanes in Washington, United States, August ushers in a noticeable decline in wind speeds, recording an average of just 1.9 m/s (4 mph). This is the lowest point of the year, following a gradual decrease from the more breezy months of spring. Notably, July, typically a peak summer month, also bears witness to a diminishing breeze, reaching only 2.2 m/s (5 mph). The trend clearly illustrates a shift as summer transitions to fall—while the wind may be whispering softly in August, September promises a slight resurgence, raising expectations for a more invigorating breeze. This gentle lull in wind speed paints a tranquil picture of late summer, inviting residents and visitors alike to enjoy the warm, still air before autumn claims the landscape.
The weather in Washington 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 Washington and find detailed weather information for every month.
August and January in Washington, D.C., present a striking contrast in weather. August features much warmer temperatures, with averages around 25°C (77°F) and highs reaching up to 37°C (99°F), accompanied by significant humidity at 72%. In contrast, January plunges to much lower temperatures, with an average of 3°C (37°F) and potential lows of -15°C (5°F), along with a higher humidity level of 84%. Precipitation also varies, with August receiving 140 mm (5.5 in) over about 15 days, while January sees only 61 mm (2.4 in) across approximately 8 days. For more detailed insights on January's weather, visit Washington weather in January.
August and February present stark contrasts in weather. In August, temperatures soar with a minimum of 14°C (58°F) and an average of 25°C (77°F), peaking at a sweltering 37°C (99°F). The month experiences considerable rainfall, totaling 140 mm (5.5 in) over approximately 15 days, with humidity levels averaging 72%. In contrast, February brings a chill, featuring a drastic drop in temperatures, with a minimum of -16°C (4°F) and an average of just 5°C (41°F), though it can still reach a maximum of 28°C (82°F) on warmer days. Precipitation in February is slightly lower at 98 mm (3.9 in) across about 11 days, coupled with higher humidity at 83%. For more insights into February weather, check out Washington weather in February.
August and March present strikingly different weather conditions. In August, temperatures can soar with a maximum of 37°C (99°F), making it the warmest month, while the average temperature hovers around a comfortable 25°C (77°F). However, it also experiences considerable humidity at 72% and significant rainfall, with about 140 mm (5.5 in) over 15 days. In contrast, March is characterized by much cooler temperatures, with highs reaching only 28°C (83°F) and average temperatures sitting at 8°C (46°F), while lows can plummet to -7°C (20°F). Rainfall in March totals 87 mm (3.4 in) over about 10 days, but the humidity is slightly higher at 83%. For a closer look at the weather in March, you can visit Washington weather in March.
August and April offer distinctly different weather experiences. In August, temperatures range from a mild 14°C (58°F) to a scorching 37°C (99°F), with an average of 25°C (77°F) and a relatively high humidity of 72%. The month also sees significant rainfall, totaling 140 mm (5.5 in) over approximately 15 days. In contrast, April presents cooler temperatures, with a minimum of -2°C (28°F), an average of 14°C (57°F), and a maximum of 32°C (91°F). While it receives less rainfall at 100 mm (4.0 in) over 11 days, April has a slightly higher humidity level at 81%. For more details on April's climate, check out Washington weather in April.
When comparing the weather in August and May, a significant difference in temperature is evident. In August, temperatures range from a minimum of 14°C (58°F) to a blistering maximum of 37°C (99°F), with an average of 25°C (77°F). In contrast, May sees much cooler temperatures, with a minimum of 2°C (36°F) and a maximum of 34°C (94°F), averaging at 19°C (66°F). Precipitation levels are similar, with August experiencing about 140 mm (5.5 in) over 15 days and May slightly less at 127 mm (5.0 in) over 13 days. Humidity is also noteworthy; while August has a humidity level of 72%, May is somewhat higher at 78%. For more detailed insights, you can check out the full overview here: Washington weather in May.
In comparing the weather between August and June, we see some notable differences. August typically experiences warmer temperatures, with a minimum of 14°C (58°F) and an average of 25°C (77°F), compared to June's minimum of 9°C (48°F) and an average of 24°C (75°F). The maximum temperatures in both months are similar, with August reaching up to 37°C (99°F) and June peaking at 36°C (98°F). August also tends to be wetter, with 140 mm (5.5 in) of precipitation over 15 days, whereas June records slightly less at 118 mm (4.7 in) over 12 days. Additionally, June has a higher humidity level of 79% compared to August's 72%. For more details on June weather, you can check Washington weather in June.
When comparing the weather in August and July, we see some notable differences. In August, the temperatures range from a minimum of 14°C (58°F) to a maximum of 37°C (99°F), with an average temperature of 25°C (77°F). This month experiences slightly less precipitation, totaling 140 mm (5.5 in) over 15 days, and the humidity averages around 72%. In contrast, July tends to be warmer, with temperatures ranging from a minimum of 15°C (59°F) to a maximum of 38°C (101°F), and an average of 27°C (81°F). Additionally, July receives more rainfall at 157 mm (6.2 in) over 12 days, with humidity at 74%. For more detailed information, you can check Washington weather in July.
August and September present contrasting weather patterns, reflecting the transition from summer to early autumn. In August, temperatures typically range from a minimum of 14°C (58°F) to a maximum of 37°C (99°F), with an average of 25°C (77°F), while September sees a drop, with minimums at 5°C (42°F) and an average of 22°C (72°F). Precipitation is more prevalent in August, with 140 mm (5.5 in) across 15 days, compared to September's 95 mm (3.8 in) over 11 days. Humidity remains fairly high in both months, with September at 75% and August slightly lower at 72%. To explore more about September weather specifics, you can visit Washington weather in September.
In comparing the weather between August and October, significant differences can be observed in temperature and precipitation patterns. August typically experiences higher average temperatures, ranging from a minimum of 14°C (58°F) to a maximum of 37°C (99°F), while October sees a notable drop, with temperatures ranging from a minimum of 1°C (34°F) to a maximum of 36°C (97°F). This change corresponds with a decrease in average daily temperatures, with August averaging around 25°C (77°F) compared to October's average of 17°C (62°F).
Additionally, August faces more precipitation, totaling 140 mm (5.5 in) over approximately 15 days, compared to October's 104 mm (4.1 in) falling over 9 days. However, October tends to be slightly more humid, with humidity levels at 81% compared to August's 72%. For a detailed look at what to expect during October, you can check out Washington weather in October.
August and November present contrasting weather conditions. In August, temperatures soar, with minimums around 14°C (58°F) and maximums reaching up to 37°C (99°F), accompanied by high humidity levels of 72%. The month also sees a considerable amount of rainfall, totaling 140 mm (5.5 in) over approximately 15 days. In stark contrast, November experiences much cooler average temperatures, hovering around 8°C (47°F), with minimums dropping to -6°C (21°F) but maximums still reaching 25°C (78°F). The month is drier, with only 81 mm (3.2 in) of precipitation across about 7 days, yet humidity levels rise to 85%. For a more in-depth look at weather specifics, you can explore Washington weather in November.
August and December present stark contrasts in weather. In August, temperatures range from a mild 14°C (58°F) at night to a scorching maximum of 37°C (99°F) during the day, with an average of 25°C (77°F). The month experiences considerable rainfall, totaling 140 mm (5.5 in) over approximately 15 days, contributing to a humidity level of 72%. In contrast, December’s weather is markedly colder, with temperatures dropping to a minimum of -10°C (13°F) and peaking at 20°C (69°F), averaging just 5°C (41°F). Precipitation decreases to 93 mm (3.7 in) across about 9 days, while humidity increases to 84%. For more details, you can explore the specifics of Washington weather in December.
August in Washington is a vibrant month, marked by warmer temperatures and increased humidity that sets it apart from the rest of the year. As the summer reaches its zenith, residents and visitors can expect a mix of scorching days and muggy nights, making outdoor activities both enjoyable and challenging. With an average temperature of 25°C, the month often feels hot and sticky, complemented by around 15 days of precipitation that can bring much-needed relief from the heat but also add to the humidity. If you want to understand how these conditions fit within the broader context of the city’s weather, explore more at Washington Climate.