Last updated: February 24, 2025
August in St. Louis, United States, presents a warm and humid climate, with maximum temperatures soaring to 35°C (96°F) and an average of 25°C (76°F). Nights bring a refreshing cooldown, dipping to a minimum of 12°C (54°F). This month typically experiences 130 mm (5.1 in) of precipitation over 11 days, contributing to the area's lush landscape. With humidity levels around 80%, residents and visitors can expect a vibrant, albeit muggy, summertime atmosphere, perfect for enjoying outdoor activities while staying hydrated.
In August, St. Louis basks in the warmth of summer, with temperatures reflecting a notable shift from the icy grip of winter. The average temperature hovers around 25°C (76°F), providing a comfortable climate for outdoor activities and events. On particularly warm days, the maximum temperatures can soar to 35°C (96°F), while evenings cool down slightly to a pleasant 12°C (54°F). Compared to the cooler months, August marks a peak in warmth, showcasing the city’s vibrant atmosphere. As summer fades into early fall, St. Louisans relish these hot days, taking advantage of the sun before transitioning into the refreshingly mild September.
In August, St. Louis experiences a notable uptick in precipitation, with an average of 130 mm (5.1 in) falling over 11 days. This places August among the wetter months of the year, just behind May, which receives the highest rainfall. The city's summer landscape vibrantly comes alive, supported by the generous moisture that is common during this time. Following a relatively drier June and July, August serves as a pivotal transition toward the fall, bringing in significant moisture that not only nurtures the region's lush greenery but also sets the stage for the cooling months ahead. Overall, August exhibits a consistent pattern of substantial rainfall, reinforcing its reputation as a late-summer rainmaker in St. Louis.
In August, St. Louis experiences a notable dip in humidity, averaging around 80%. This marks a continuation of the summer's high humidity but slightly less oppressive than the preceding months of June and July, which saw levels at 83% and 81%, respectively. As the summer transitions towards fall, humidity generally trends downward, with September dropping even further to 76%. This slight reprieve in August suggests a subtle shift in the weather, offering residents a breath of fresh air before the humidity begins to rise again later in the year, peaking in the winter months at an average of 85% in November. Overall, while August maintains a humid atmosphere characteristic of St. Louis summers, it hints at the approaching change of seasons.
In August, St. Louis experiences a UV Index of 10, categorizing it within the very high exposure level, which indicates a burn time of just 15 minutes. This trend of elevated UV levels has been consistent since June when the index peaked at 11, marking it as the month with the most intense solar radiation. Following this summer pattern, both July and August maintain similar high readings, reminding residents to safeguard their skin during outdoor activities. As the transition to September approaches, the UV Index will slightly decrease to 9, still presenting a considerable risk. To stay informed about UV exposure levels throughout the year, check out the detailed information at St. Louis UV Index.
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In August, St. Louis basks in a plentiful 330 hours of sunshine, marking a slight dip from July's peak but still part of a vibrant summer trend. This month continues the city's warm embrace of bright, sunny days, following a steady rise from the 125 hours seen in January. As the year progresses, each month showcases an increase in sunshine, culminating in the sunny heights of June and July. After August, the sunlight begins to taper off into autumn, leading to September's still generous 290 hours, before settling into the softer hues of fall. This pattern underscores St. Louis as a city that thrives in radiant summer days, inviting residents and visitors alike to revel in the warmth before the cooler months arrive.
In St. Louis, August presents a moderate chance of sunny weather, standing at 47%, which is just shy of the peak seen in September at 64%. This month's likelihood of sunshine reflects a gradual improvement from the early summer months, where June and July reported 41% and 51% respectively. Interestingly, while August holds a fairly robust chance of sun, it is also part of a broader trend where summer months generally experience more sunshine compared to the chillier winter and early spring months. As the year progresses, the likelihood of sun tends to rise, peaking as summer transitions into fall, making August a somewhat promising time for those eager to soak up some rays before autumn approaches.
As summer gently concludes in St. Louis, August offers a delightful balance of daylight, boasting 13 hours of sun. This marks a gradual tapering from the glorious heights of 14 hours experienced in June and July, creating a smooth transition into the shorter days of early fall. Following the vibrant energy of midsummer, August’s daylight duration still provides ample opportunities for outdoor activities, yet hints at the upcoming seasonal changes. As daylight hours gradually decrease in September, the lingering warmth of August serves as a reminder of summer's fleeting embrace, inviting locals to savor the last rays of the sun before autumn settles in.
In St. Louis during the month of August, the average wind speed gently settles at 2.4 m/s (5 mph), reflecting a trend of lower winds typical for summer. As the sultry heat of July passes, August experiences only a slight increase in breeze from the 2.1 m/s registered in the previous month. This lull in wind continues the pattern observed from June through August, where speeds dwindle, creating a more serene atmosphere. However, as the season transitions into September, the winds begin to pick up again, hinting at the brisker, more invigorating conditions to come in the fall months. Thus, while August embodies a quieter, calmer wind profile, it lays the groundwork for the refreshing shifts in September and beyond.
The weather in St. Louis 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 St. Louis and find detailed weather information for every month.
August and January present starkly contrasting weather conditions. In August, temperatures range from a cool 12°C (54°F) at night to a scorching 35°C (96°F) during the day, accompanied by high humidity levels of 80%. The month also sees significant rainfall, with 130 mm (5.1 in) spread over 11 days. In contrast, January brings much colder temperatures, with a minimum of -22°C (-7°F) and a maximum of 19°C (67°F), leading to an average temperature of around 0°C (32°F). The precipitation is less frequent, with 76 mm (3.0 in) over just 8 days, while humidity remains relatively high at 82%. For more details on the winter conditions, you can check St. Louis weather in January.
August and February present stark contrasts in weather conditions. August boasts a much warmer climate with average temperatures around 25°C (76°F) and maximum highs reaching 35°C (96°F), accompanied by significant precipitation of 130 mm over 11 days. In contrast, February experiences colder temperatures with an average of just 2°C (35°F), and lows plummeting to -19°C (-1°F), while precipitation is lower at 80 mm over 10 days. Despite both months sharing a humidity level of 80%, the overall weather experience couldn't be more different. For more detailed information, check out St. Louis weather in February.
August and March present a striking contrast in weather conditions. August boasts higher temperatures, with minimums around 12°C (54°F) and maxing out at 35°C (96°F), while March experiences much colder temperatures, starting at a minimum of -17°C (2°F) and peaking at 27°C (81°F). Precipitation levels are quite similar, with August reporting 130 mm over 11 days and March slightly higher at 131 mm over 12 days. Both months also share the same high humidity level of 80%, making them feel more intense in terms of moisture. For more details about the weather in March specifically, check out St. Louis weather in March.
When comparing the weather in August and April, notable differences emerge. August experiences higher average temperatures, ranging from a minimum of 12°C (54°F) to a maximum of 35°C (96°F), whereas April sees a cooler range with temperatures fluctuating between -4°C (24°F) to a maximum of 30°C (87°F). Both months have similar precipitation levels, with August receiving 130 mm (5.1 in) and April slightly less at 129 mm (5.1 in), although both months experience rain on approximately 11 days. Humidity remains consistent in both months at around 80%, contributing to a muggy feel in August, while April's cooler temperatures may make the humidity more bearable. For more detailed information on April weather, visit St. Louis weather in April.
When comparing the weather in August and May, several notable differences emerge. August tends to be warmer, with average temperatures reaching 25°C (76°F) and maximums hitting up to 35°C (96°F), while May has a cooler average of 20°C (68°F) and peaks at 34°C (94°F). Precipitation levels in August total 130 mm (5.1 in) over about 11 days, slightly lower than May's 145 mm (5.7 in) over 14 days, indicating that May is generally wetter. Humidity levels are fairly similar, with August at 80% and May slightly higher at 82%. For a deeper dive into the specifics of May weather, you can check out St. Louis weather in May.
In comparing August and June weather, both months exhibit similar minimum temperatures, with lows around 12°C (54°F), yet June tends to be slightly warmer on average, reaching 25°C (77°F) compared to August's 25°C (76°F). While August and June both experience precipitation on 11 days, August has higher rainfall, totaling 130 mm (5.1 in), whereas June sees 101 mm (4.0 in). Additionally, humidity levels are somewhat elevated in June at 83%, compared to August's 80%. For a more detailed look at June's weather specifics, you can visit St. Louis weather in June.
When comparing the weather in August to that of July, August tends to be slightly cooler, with average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 35°C (96°F), while July features higher temperatures, peaking at 38°C (101°F). Additionally, August experiences more precipitation, totaling 130 mm (5.1 in) across 11 days, compared to July’s 97 mm (3.8 in) over the same number of days. Humidity levels remain relatively consistent, with August at 80% and July at 81%. For more detailed insights on July weather, you can visit St. Louis weather in July.
August weather is characterized by warmer temperatures, featuring a minimum of 12°C (54°F) and an average of 25°C (76°F), with maximums reaching up to 35°C (96°F). In contrast, September sees cooler nights with a minimum temperature of 7°C (45°F) and a slightly lower average of 22°C (73°F). Both months can experience heat, but September's overall temperatures are more temperate, despite matching August's peak maximum. Additionally, August is significantly wetter, with 130 mm (5.1 in) of precipitation over 11 days compared to September's 56 mm (2.2 in) across 7 days. Humidity also drops slightly from 80% in August to 76% in September, contributing to a more comfortable feel. For more detailed information, check St. Louis weather in September.
In August, the weather is characterized by warm temperatures, with an average of 25°C (76°F) and highs reaching up to 35°C (96°F), accompanied by high humidity levels of 80%. Rainfall is also notable, with about 130 mm (5.1 in) of precipitation over 11 days. Conversely, October brings a significant drop in temperatures, with an average of 15°C (59°F) and lows dipping to -4°C (26°F). Although October experiences slightly less precipitation at 105 mm (4.1 in) over the same number of rainy days, the humidity level decreases to 76%. This transition from the sweltering summer heat of August to the cooler autumn climate in October can be further explored in detail here: St. Louis weather in October.
August and November exhibit stark contrasts in weather conditions. In August, temperatures range from a mild 12°C (54°F) at night to a sweltering 35°C (96°F) during the day, accompanied by high humidity levels of 80% and significant precipitation of 130 mm (5.1 in) over 11 days. Conversely, November brings a much cooler climate, with temperatures dipping down to a chilling -13°C (9°F) at night and averaging around 7°C (44°F) during the day. The month experiences lower precipitation at 75 mm (2.9 in) over 9 days, alongside slightly higher humidity at 85%. For more detailed insights into November weather, you can visit St. Louis weather in November.
August and December present stark contrasts in weather. August enjoys warm temperatures, with averages around 25°C (76°F) and peaks reaching as high as 35°C (96°F). Additionally, it experiences significant humidity at 80% and ample rainfall, totaling 130 mm (5.1 in) over 11 days. In comparison, December features much colder conditions, with average temperatures dropping to around 4°C (39°F) and minimums plummeting to -18°C (0°F). While it receives less precipitation, only 59 mm (2.3 in) over 7 days, the humidity remains relatively high at 86%. For those looking to understand the specifics of winter conditions, check out St. Louis weather in December.
August in St. Louis presents a distinctive character compared to other months, characterized by warm temperatures and high humidity that can make the air feel quite heavy. With an average temperature of around 25°C, it is one of the warmest months, occasionally reaching up to 35°C, contrasting sharply with the cooler winter months. The likelihood of encountering precipitation over approximately 11 days adds a touch of unpredictability to the otherwise sultry atmosphere. While other months may enjoy drier conditions, August's humidity levels hover around 80%, creating a summer vibe that evokes a sense of both warmth and refreshment. To explore further insights into the weather patterns throughout the year, visit St. Louis Climate.