Last updated: February 24, 2025
In August, Rapid City experiences a wide range of temperatures, with maximums soaring up to 37°C (98°F) and an average of 20°C (69°F), while dipping to a cool 7°C (44°F) at night. This month sees a notable precipitation total of 57 mm (2.2 in) over approximately 12 days, contributing to a relatively high humidity level of 85%. The varied climate not only enhances the vibrant summer landscape but also invites both residents and visitors to embrace the unique weather patterns of this charming region.
In August, Rapid City experiences a warm embrace as summer approaches its conclusion. The temperatures range from a pleasant 7°C (44°F) at night to a striking 37°C (98°F) during the day, creating a rich tapestry of warmth perfect for outdoor activities. This month boasts a comfortable average of 20°C (69°F), reflective of the gradual warming trend that starts in June, peaks in July, and remains delightful as summer wanes. As the city transitions from the intense heat of July, August offers a balmy atmosphere, making it an ideal time for exploring the stunning landscapes and enjoying local festivities before the cooler fall temperatures set in.
In August, Rapid City experiences a moderate shift in precipitation, receiving 57 mm (2.2 in) of rain over 12 days. This amount is a notable decrease from the bustling summer months of June (72 mm) and July (96 mm), suggesting a gradual transition towards the drier fall. The rainfall becomes more sporadic as summer wanes, marking a clear trend where the intensity of precipitation starts to taper off. Despite this, August still holds onto a significant portion of summer's moisture, providing lush greenery before the cooler months approach. The city's climate showcases a rhythm of rainfall, with August acting as a bridge between the wetter, vibrant summer and the milder, drier autumn days ahead.
In August, Rapid City experiences a notable peak in humidity, consistently recorded at 85%, a level that mirrors the humidity levels of the preceding month, July. This period marks the zenith of a gradual rise that began in late spring, with June's humidity already climbing to 84%. Following the summer months, a decline is anticipated as temperatures cool in September, bringing humidity down to 76%. Overall, the late summer months showcase a significant increase in moisture levels compared to the early part of the year, where January and February recorded considerably lower humidity levels at 73% and 78%, respectively. This trend underscores the seasonal shift in Rapid City's climate, where the summer months bring higher humidity—creating a more vibrant, lush environment.
In August, Rapid City experiences a UV Index of 10, placing it in the very high exposure category with a burn time of just 15 minutes. This follows a trend established in the summer months, where the UV Index peaks at 11 in June and July. As the sun blazes down, it's essential to stay vigilant, as the intensity begins to taper slightly into September, where the index drops to 8. Overall, the summer months suggest a pattern of increasing UV exposure, prompting residents and visitors alike to take necessary precautions for skin protection. For more details on UV exposure throughout the year, visit Rapid City UV Index.
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In August, Rapid City basks in a delightful 356 hours of sunlight, showcasing its vibrant summer appeal. Following the peak sunlight months of June and July, which boast 376 and 382 hours respectively, August maintains a strong presence, even as the days begin to shorten. This month marks a transitional phase, where the warmth of summer lingers but hints at the incoming fall. With sunlight hours gradually tapering off in September to 288 hours, August serves as a golden wrap-up to the sun-soaked days of summer, inviting outdoor adventures and evening gatherings while enjoying the last of the season's warmth.
In Rapid City, August marks a peak in sunny weather, boasting a 72% chance of sunshine—the highest probability for any month of the year. This trend aligns with the steady increase in sunny days starting from the cooler months, where January through May sees chances dip below 50%. As summer unfolds, June and July provide a warm, inviting environment with 67% sunshine, but it’s August that truly shines. Moving into the fall, the likelihood of sunny days remains strong, with September also holding a commendable 67% chance. This progression not only highlights August as an ideal time for outdoor activities but also emphasizes the region's climate shift towards sunnier, warmer days as the summer season reaches its zenith.
As summer gives way to the early whispers of autumn, August in Rapid City witnesses a decline in daylight duration, offering approximately 13 hours of light each day. This shift follows the peak of 15 hours experienced in both June and July, signifying the transition from the vibrant long days of summer to the shorter, crisper days of fall. Throughout the year, daylight begins its gradual ascent from a mere 9 hours in January to a summer zenith, then begins its slow descent by the time August rolls around. As the twilight hours become more pronounced, they herald a new season filled with the colors and cooler temperatures of September, reminding us of nature's rhythm and the changing landscape.
In August, Rapid City experiences a gentle breeze, with an average wind speed of 3.2 m/s (7 mph), mirroring the calmer winds of July. This trend of light winds continues from earlier in the summer, suggesting a tranquil atmosphere perfect for outdoor activities. Following the early months of the year, when winds picked up to more robust speeds, August marks a notable dip in wind intensity, resembling the stillness that precedes autumn's approach. As the season transitions into September, Rapida City's winds are expected to slightly increase again, reflecting a subtle but distinct rhythm in the region's weather patterns throughout the year.
The weather in Rapid City 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 Rapid City and find detailed weather information for every month.
August and January present starkly contrasting weather conditions. In August, temperatures range from a pleasant 20°C (69°F) on average, with highs soaring to 37°C (98°F), accompanied by high humidity levels at 85%. This month sees around 57 mm (2.2 in) of precipitation, typically spread over 12 days. In contrast, January is much colder, with average temperatures plummeting to -3°C (27°F) and lows reaching a chilling -26°C (-14°F). Precipitation is minimal in January, with only 14 mm (0.5 in) falling over just four days and humidity at 73%. For a deeper dive into January's climate specifics, check out Rapid City weather in January.
August and February represent two extremes in weather conditions. In August, temperatures can soar from a mild 7°C (44°F) to a scorching maximum of 37°C (98°F), with an average around 20°C (69°F). This month is characterized by high humidity at 85% and moderate precipitation of 57 mm (2.2 in) over approximately 12 days. In stark contrast, February sees the mercury plunge, with minimum temperatures dropping as low as -29°C (-19°F) and averaging around -6°C (22°F). Although February can also peak at a balmy 21°C (69°F), it experiences significantly lower precipitation at 27 mm (1.1 in) over just 7 days, coupled with a lower humidity level of 78%. For more detailed weather insights, check out Rapid City weather in February.
In comparing the weather of August and March, it's clear that these months present starkly different climate conditions. August boasts much warmer temperatures, with average highs reaching 20°C (69°F) and peaks of up to 37°C (98°F), accompanied by high humidity levels at 85%. In contrast, March experiences much colder temperatures, with average highs of only 2°C (36°F) and a chilly minimum of -26°C (-14°F). While August records 57 mm (2.2 in) of precipitation over about 12 days, March has a slightly lower total of 44 mm (1.7 in) over 8 days, coupled with a lower humidity of 64%. For those interested in detailed information about the weather during March, you can visit Rapid City weather in March.
In comparing the weather of August and April, it's evident that the summer month brings significantly warmer temperatures, with averages around 20°C (69°F) and a maximum of 37°C (98°F), while April's temperatures range much lower, peaking at 25°C (77°F). Despite April's cooler climate, it experiences slightly higher precipitation levels at 73 mm (2.9 in) compared to August's 57 mm (2.2 in), although rainfall occurs over a similar number of days—11 in April versus 12 in August. Additionally, the humidity in August is notably higher at 85%, while April maintains a more moderate 66%. For further details on April's climate, visit Rapid City weather in April.
When comparing the weather in August and May, it’s evident that August experiences much warmer temperatures, with averages around 20°C (69°F) and highs reaching up to 37°C (98°F). In contrast, May has a cooler average of 11°C (53°F) and a maximum temperature of 30°C (86°F). Precipitation also differs significantly; May sees more rainfall, with 112 mm (4.4 in) over 17 days, compared to August's 57 mm (2.2 in) over 12 days. Notably, August's humidity is higher at 85%, while May maintains a lower humidity level of 74%. For a more comprehensive look at May's weather, you can refer to Rapid City weather in May.
When comparing the weather in August to June, we can observe some notable differences. August experiences a broader temperature range, with a minimum of 7°C (44°F) and a maximum of 37°C (98°F), while June's temperatures are slightly cooler, ranging from a minimum of 4°C (40°F) to a maximum of 36°C (97°F). The average temperature in both months is fairly similar, hovering around 20°C (69°F) in August and 19°C (67°F) in June. Precipitation is heavier in June, totaling 72 mm (2.8 in) over 13 days, compared to August's 57 mm (2.2 in) over 12 days. Humidity levels are quite close, with August at 85% and June at 84%. For more detailed information, you can check out Rapid City weather in June.
In comparing the weather between July and August, we see some notable differences. July typically has slightly higher temperatures, with a minimum of 9°C (49°F), an average of 22°C (72°F), and a maximum reaching 38°C (100°F). In contrast, August is a bit cooler, with temperatures ranging from a minimum of 7°C (44°F) to a maximum of 37°C (98°F). While both months experience high humidity at 85%, July sees more precipitation, totaling 96 mm (3.8 in) over 16 days, compared to August's 57 mm (2.2 in) over 12 days. For more detailed information, you can read about specific conditions in Rapid City weather in July.
August tends to be warmer and more humid compared to September, with minimum temperatures around 7°C (44°F) and an average of 20°C (69°F). The month experiences higher precipitation, totaling 57 mm (2.2 in) over 12 days and humidity levels of 85%. In contrast, September sees a noticeable drop in minimum temperatures, reaching as low as -4°C (26°F), while the average temperature decreases to 16°C (62°F). Although maximum temperatures can still reach up to 37°C (100°F), the overall precipitation is lower at 43 mm (1.7 in) over just 7 days, and humidity drops to 76%. For more detailed information, you can visit Rapid City weather in September.
August and October exhibit striking differences in weather patterns. August typically enjoys warmer temperatures, with averages around 20°C (69°F) and maximums reaching up to 37°C (98°F). In contrast, October sees a significant drop, averaging only 7°C (45°F), with minimums plunging to -18°C (-1°F). While August has high humidity levels of 85% and experiences 12 days of precipitation totaling 57 mm (2.2 in), October is less humid at 71% and has slightly lower precipitation, totaling 52 mm (2.0 in) over 8 days. For more detailed information, please refer to Rapid City weather in October.
August and November present stark contrasts in weather patterns. In August, temperatures range from a mild 7°C (44°F) at the lowest to a scorching high of 37°C (98°F), with an average of 20°C (69°F). This month also sees significant humidity at 85% and relatively frequent rainfall, totaling 57 mm (2.2 in) over approximately 12 days. In contrast, November experiences much cooler temperatures, with lows plunging to -19°C (-2°F) and an average of only 3°C (37°F), peaking at 24°C (75°F). Rainfall is minimal during this month, with only 17 mm (0.7 in) over 5 days, and humidity drops to 73%. For more detailed information, you can explore Rapid City weather in November.
In August, the weather in Rapid City is characterized by warm temperatures, ranging from a minimum of 7°C (44°F) to a scorching maximum of 37°C (98°F), with an average of around 20°C (69°F). The high humidity level of 85% and significant precipitation of 57 mm (2.2 in) over 12 days contribute to a sultry atmosphere.
Conversely, December brings a stark contrast with frigid temperatures dropping as low as -23°C (-10°F) and averaging around -1°C (30°F). The maximum temperature reaches a milder 21°C (70°F), but overall, it’s a much cooler season. December experiences less precipitation, totaling 28 mm (1.1 in) over just 6 days, and the humidity decreases to 75%. For more details on the December climate, check out Rapid City weather in December.
As August unfolds in Rapid City, the weather crystallizes a distinct blend of warmth and variability, setting it apart from earlier summer months. With daytime temperatures soaring to heights of 37°C (98°F), it offers opportunities for sun-soaked adventures, while nights bring a refreshing coolness down to 7°C (44°F). The air is often thick with humidity reaching 85%, enhancing the sultry feel, as the region experiences frequent showers with around 57 mm (2.2 in) of rain over a dozen days. This month embodies a transitional phase, giving way to the crispness of fall while still clinging to summer's embrace. For a deeper dive into how August compares with the broader climate patterns in Rapid City, visit Rapid City Climate.