Last updated: August 31, 2025
In August, San Juan, Puerto Rico experiences a tropical climate characterized by warm temperatures and significant humidity. With maximum temperatures reaching around 32°C (90°F) and an average of 28°C (82°F), days are typically hot and inviting. Nights offer a respite, cooling to a comfortable 24°C (76°F). However, visitors should be prepared for occasional rain, as the city receives an average of 99 mm (3.9 in) of precipitation over about 18 days, resulting in a humidity level around 80%. This blend of warmth and moisture creates a vibrant atmosphere, perfect for exploring the city's rich culture and stunning landscapes.
In August, San Juan, Puerto Rico, enjoys a tropical climate characterized by warm temperatures that remain consistently inviting. Minimum temperatures hover around 24°C (76°F), while average highs reach 32°C (90°F), making it one of the warmest months of the year. The steady warmth continues from July, with August mirroring its average temperature of 28°C (82°F). This consistency signals a summer that lingers, perfect for beach outings and vibrant outdoor festivities. As the month progresses, the heat can intensify, but the refreshing ocean breezes provide a lovely reprieve from the warmth, enticing visitors to embrace the sun-kissed paradise that is San Juan.
In August, San Juan, Puerto Rico, experiences a significant uptick in precipitation, with an average of 99 mm (3.9 in) over 18 rainy days. This marks a noteworthy increase compared to the preceding months, where rainfall steadily rose from 38 mm in January to 87 mm in July. The city's tropical climate culminates in August, setting the stage for the ensuing wet season, which peaks in September with an alarming 173 mm (6.8 in). The pattern underscores a trend of increasing rainfall as summer transitions into autumn, compelling residents to prepare for an intensifying monsoon that often shapes the landscape and daily life in this vibrant Caribbean locale.
August in San Juan, Puerto Rico, marks a peak in humidity levels, consistently reaching around 80%—a trend mirrored from the previous month of July. This summer high aligns with the region's overall humidity oscillation throughout the year, which tends to be more pronounced during the warmer months. Following the relatively lower levels seen in the earlier part of the year, from January to May, where humidity hovered around 75%, the rising trend becomes evident as the tropical heat of summer intensifies. As September approaches, there is a slight decrease to 79%, but the humidity remains notably high, characterizing the lush and vibrant atmosphere of the Caribbean during this time.
August in San Juan, Puerto Rico, maintains a consistent and intense UV Index of 13, classified as extreme. This level of UV radiation means residents and visitors alike should be cautious, with a burn time as quick as 10 minutes for unprotected skin. As summer peaks, the data shows a trend where UV levels remain high throughout the month, mirroring the intensity observed in previous months like May and June. As we transition toward fall, the UV Index starts to taper off, but in August, the message is clear: prioritize skin protection to enjoy the sun safely. For more detailed information, check out the San Juan UV Index.
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August in San Juan, Puerto Rico is a delightful continuation of the sun-soaked summer, clocking in at 349 hours of glorious sunshine. This month marks a slight dip from the peak brightness of May and June, which basked in over 350 hours each, yet still offers a generous bounty of sunshine to enjoy. The trend throughout the summer showcases a vibrant consistency, with only minor fluctuations; even as the season transitions into fall, the sunshine remains plentiful compared to the cooler months ahead. With August's warmth, beach activities, and sunset strolls, visitors can revel in the beauty of San Juan's enduring summer vibes—an inviting embrace before the days begin to shorten.
In San Juan, Puerto Rico, August experiences a 41% chance of sunny weather, reflecting a dip in sunshine compared to the earlier months of the year. The trend shows a noticeable increase in sun chances from February’s robust 70% down to the lower probabilities found during the summer peak. Notably, June sees the lowest likelihood at 24%, followed by July with 43%, indicating that while August may not be the sunniest month, it's a slight improvement from the intense humidity of mid-summer. As the year progresses into September, the sun's return begins to wane slightly, settling back to 48%. This fluctuation underscores the dynamic weather patterns of the region, making August a time when beachgoers might need to keep an eye on the skies while enjoying the tropical warmth.
In August, the residents of San Juan, Puerto Rico enjoy approximately 12 hours of daylight, a slight dip from the peak of 13 hours in the summer months of June and July. This shift marks a transitional phase as the days gradually shorten leading into the cooler months. Interestingly, daylight duration remains consistent with both September and April—highlighting a natural symmetry in the changing seasons. As autumn approaches, San Juan continues to bask in ample sunlight, allowing inhabitants to make the most of the vibrant outdoor lifestyle that characterizes this beautiful Caribbean locale.
In August, the wind in San Juan, Puerto Rico maintains a pleasant average speed of 4.6 m/s (10 mph), offering a refreshing breeze amid the tropical warmth. This slight dip from the peak of 5.3 m/s in July signals the transition towards the quieter months, as the summer winds begin to calm ahead of the fall. Interestingly, August's wind speed is a touch higher than the earlier spring months like April and March, which recorded lower averages of 3.8 m/s and 4.5 m/s respectively. As the year progresses into September, we see a more significant reduction to 3.2 m/s, highlighting a noticeable trend of diminishing winds as the island gears up for the autumn and winter seasons. This gentle August breeze is an ideal companion for leisurely evenings, making it a time to savor the last moments of summer before the winds shift.
Weather in San Juan varies notably across the year, with each month offering distinct climate conditions. This page compares August’s weather to other months in San Juan, focusing on differences in temperature, rainfall, humidity, and UV levels.
August typically brings warmer and more humid weather compared to January. With average temperatures around 28°C (82°F) and highs reaching up to 32°C (90°F), it is noticeably hotter, while January's average is slightly cooler at 25°C (77°F) with a maximum of 29°C (85°F). Additionally, August experiences more significant rainfall, averaging 99 mm (3.9 in) over 18 days, in contrast to January, which sees only 38 mm (1.5 in) over 12 days. This makes January a drier and slightly less humid month, with humidity levels around 76% compared to August's 80%. For a more detailed look at January weather, visit San Juan weather in January.
When comparing the weather in August and February, there are notable differences in temperature, precipitation, and humidity. August features a warmer climate, with average temperatures reaching 28°C (82°F) and maximums hitting 32°C (90°F). In contrast, February enjoys milder temperatures, with averages of 25°C (77°F) and maximums up to 29°C (85°F). Precipitation is also more substantial in August, with 99 mm (3.9 in) spread over 18 days, compared to February's lighter rains of 43 mm (1.7 in) over 12 days. Additionally, humidity levels are slightly higher in August at 80%, compared to 75% in February. For more detailed insights, you can explore the San Juan weather in February.
August and March present distinct weather patterns, showcasing the transition from summer to spring. In August, temperatures are warmer with a minimum of 24°C (76°F) and an average of 28°C (82°F), reaching a maximum of 32°C (90°F). This month also experiences higher rainfall, averaging 99 mm (3.9 in) over 18 days, combined with 80% humidity. Conversely, March offers slightly cooler temperatures, with a minimum of 21°C (71°F) and an average of 25°C (77°F), peaking at 30°C (86°F). Rainfall is lower in March, totaling 67 mm (2.6 in) over 14 days, and the humidity is somewhat reduced at 74%. For more detailed information on March weather, visit San Juan weather in March.
When comparing the weather in August and April, it’s clear that August tends to be warmer and wetter. In August, the average temperature hovers around 28°C (82°F), with a minimum of 24°C (76°F) and a maximum reaching 32°C (90°F). The month also sees substantial rainfall, accumulating 99 mm (3.9 in) over 18 days, and maintains a high humidity level of 80%. Conversely, April offers slightly cooler temperatures, averaging 26°C (78°F), with a minimum of 22°C (71°F) and a maximum of 31°C (88°F). It experiences less rainfall, with a total of 56 mm (2.2 in) over just 10 days and a humidity level of 75%. For a detailed look at the weather in April, check out San Juan weather in April.
When comparing the weather in August and May, both months experience similar high temperatures, with August averaging 28°C (82°F) and May slightly lower at 27°C (80°F). However, August tends to be more humid, with humidity levels around 80% compared to May’s 75%. Additionally, August sees more rainfall, with 99 mm (3.9 in) of precipitation over 18 days, while May has a lower total of 64 mm (2.5 in) of rain spread across 13 days. For a more detailed look at the weather conditions during May, you can check San Juan weather in May.
When comparing the weather in August and June, both months exhibit similar high temperatures, with maximums reaching up to 32°C (90°F). However, August tends to be slightly warmer overall, with an average temperature of 28°C (82°F), compared to June's average of 27°C (81°F). Precipitation levels also differ, with August experiencing more rain, totaling 99 mm (3.9 in) across 18 days, while June averages 68 mm (2.7 in) over 15 days. Additionally, humidity is marginally higher in August at 80%, compared to June's 77%. For further insights on June's weather, you can check San Juan weather in June.
In comparing the weather of August and July, we see that both months share similar temperature ranges, with minimums of 24°C (76°F), average temperatures of 28°C (82°F), and maximums reaching 32°C (90°F). However, August experiences slightly higher precipitation levels, totaling 99 mm (3.9 in) compared to July's 87 mm (3.4 in). Despite the increased rainfall, both months maintain a consistent humidity level of 80% and have rain for 18 days. For more detailed information on July's climate, you can check out San Juan weather in July.
August and September share similar temperature profiles, with both months experiencing minimums of 24°C (76°F), average temperatures of 28°C (82°F), and maximums reaching up to 32°C (90°F). However, September sees a notable increase in precipitation, totaling 173 mm (6.8 in) over 23 days, compared to August's 99 mm (3.9 in) across 18 days. Despite the slight decrease in humidity from 80% in August to 79% in September, the latter month is generally wetter, making for a more tumultuous weather experience. For a detailed look at September's weather patterns, visit San Juan weather in September.
In August, the weather is characterized by warmer temperatures, with a minimum of 24°C (76°F) and an average of 28°C (82°F), reaching a maximum of 32°C (90°F). The month experiences significant rainfall, totaling 99 mm (3.9 in) over 18 days, alongside high humidity levels at around 80%.
In contrast, October's weather is slightly cooler with a similar minimum temperature of 24°C (75°F) but an average of 27°C (81°F), peaking at a maximum of 32°C (89°F). However, October sees increased precipitation, with 145 mm (5.7 in) falling over 22 days, while humidity decreases slightly to 78%. For more detailed information, you can check San Juan weather in October.
August and November weather in San Juan exhibit some similarities but also notable differences. August tends to be slightly warmer, with average temperatures peaking at 28°C (82°F) compared to November's 26°C (80°F). Both months feature high humidity levels; however, August is marginally more humid at 80%, while November sits at 78%. In terms of precipitation, November has a slightly higher total of 106 mm (4.2 in) over 16 days, compared to August's 99 mm (3.9 in) across 18 days. For more detailed information, you can check out San Juan weather in November.
In comparing the weather between August and December, both months feature similar minimum temperatures, with August averaging at 24°C (76°F) and December slightly cooler at 23°C (73°F). However, August is noticeably warmer on average with temperatures reaching 28°C (82°F) compared to December's 26°C (78°F). The maximum temperatures are also similar, peaking at 32°C (90°F) in August and 31°C (87°F) in December. Precipitation is significantly higher in August, reaching 99 mm (3.9 in) over 18 days, while December sees a decrease to 51 mm (2.0 in) across 16 days, indicating a dryer atmosphere. Additionally, humidity levels are slightly elevated in August at 80%, compared to 76% in December. For more detailed information on the weather in December, you can check San Juan weather in December.
August in San Juan brings a blend of warm temperatures and high humidity, distinguishing it from the milder months of the year. With maximums soaring around 32°C (90°F) and an average linger around 28°C (82°F), visitors can expect sultry conditions. The month also sees significant precipitation, with showers likely on nearly half of the days, resulting in lush landscapes and vibrant scenery. While the tropical warmth and moisture enhance the island's lush beauty, it also calls for preparations against sudden rain. For a deeper understanding of the weather patterns throughout the year, check out San Juan Climate.