Last updated: August 21, 2025
Experience the tropical charm of Rio San Juan, Dominican Republic, in September, where temperatures typically range from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), creating a warm and inviting atmosphere. The average temperature hovers around 27°C (82°F), making it an ideal time for beachgoers. However, be prepared for frequent rain, as the region sees 145 mm (5.7 inches) of precipitation over 20 days this month, contributing to a humidity level of 73%. Embrace the lush landscapes and vibrant culture, but don’t forget your umbrella for those afternoon showers!
In September, temperatures in Rio San Juan, Dominican Republic consistently reflect the warm, tropical climate of the region. With lows around 24°C (76°F) and averages of 27°C (82°F), the month offers a comforting warmth perfect for beach outings. The maximum temperature can reach up to 31°C (88°F), signifying a slight peak compared to previous months. This trend of increasing warmth from the cooler months of the year highlights a comforting stability in temperatures, making September a delightful time for visitors seeking both sun and relaxation. As the month progresses, the warm embrace of summer lingers just a bit longer, inviting both travelers and locals to enjoy the stunning coastal scenery.
September marks a significant uptick in precipitation for Rio San Juan, with 145 mm (5.7 in) of rainfall recorded, making it the wettest month of the year. This surge contributes to the region's lush landscapes and vibrant ecosystems. Coinciding with this increase, September experiences around 20 rainy days, reflecting the transition into the heart of the rainy season. Following the relatively drier months of June and July, the rains in September pave the way for a rich environment, crucial for agriculture and local flora. The pattern observed in this month sets the stage for the continued rainy season, characterized by consistent rainfall into the fall.
As summer fades into fall in Rio San Juan, the humidity begins to climb noticeably, peaking at 73% in September. This marks a significant rise from the drier months earlier in the year, which saw levels as low as 57% in May and June. The transition into autumn not only brings a shift in temperature but also a marked increase in moisture, following a gradual ascent from 63% in July and a notable leap to 71% in August. As the tropical climate continues to exert its influence, September stands out as a month where humidity levels surge, setting the stage for the lush environments characteristic of this beautiful Dominican destination.
As summer fades into September in Rio San Juan, Dominican Republic, the UV Index hovers at a significant 12, categorized as extreme, which means sun exposure can lead to burns in just 10 minutes. This trend of high UV levels persists from the peak months of March to August, where the index consistently hits 13. While September sees a slight dip, it remains essential for residents and visitors to stay vigilant about sun protection. The patterns indicate that, throughout the year, caution is crucial, especially during the peak UV months. For more detailed information about UV levels, check out Rio San Juan UV Index.
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September in Rio San Juan, Dominican Republic, offers a delightful mix of sunny days, boasting approximately 319 hours of brilliant sunshine. This marks a slight dip from the peak summer months of July and June, which saw over 360 hours of radiant warmth. However, September still holds its own, as it transitions into the fall season while maintaining a generous amount of daylight. The sun-soaked days continue to invite visitors to enjoy the stunning beaches and vibrant local culture, compelling for those who seek warmth and adventure even as the year begins to cool. Compared to the abundance of summer sunshine, September's luminosity still truly shines, making it an excellent month for travel and exploration.
As summer transitions into fall, September in Rio San Juan experiences a notable 52% chance of sunny weather, striking a balance that invites outdoor activities. This month's likelihood of sunshine is a refreshing increase from the dimmer days of June and August, which plunge to 37% and 38% respectively. Following a mix of sun and rain in the summer, September offers a pleasant embrace of warmth and brightness without the high humidity levels typical of the peak season. As the year progresses, the likelihood of sunny days picks up again dramatically, making September a lovely time to enjoy the tropical beauty of the Dominican Republic before the rainfall increases in October.
In Rio San Juan, Dominican Republic, the daylight duration exhibits a fascinating rhythm throughout the year. The descent into September sees 12 hours of daylight, mirroring the brightness of August and marking a transition from the summer's elongated days. As the year progresses from January's steady 11 hours, daylight gradually lengthens, peaking at 13 hours in May through July, offering ample sunlight for both relaxation and adventure. Following September, the duration begins its gentle decline, suggesting the impending embrace of shorter days as autumn approaches. This shift creates a dynamic interplay of light and shadow, capturing the essence of Rio San Juan's tropical allure as it moves toward the cooler months.
In September, Rio San Juan experiences a gentle lull in the wind, with an average speed of just 3.8 m/s (8 mph). This marks a noticeable dip compared to the summer months, where winds consistently hovered around 5.8 m/s (13 mph) in July. As the peak of the tropical season fades, this softer breeze offers a tranquil atmosphere, perfect for relaxing beach days or leisurely strolls along the shore. Interestingly, September's wind speed is the lowest of the year, suggesting a transition as the region prepares for a gradual increase in airflow with the onset of October. This calming respite in September invites visitors to savor the serene beauty of the Dominican Republic's coastline before the winds pick up again.
Weather in Rio San Juan varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Rio San Juan, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January offer notable differences in weather patterns. In September, temperatures typically range from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), with an average of 27°C (82°F). The month is characterized by higher humidity at 73% and considerable rainfall, accumulating 145 mm (5.7 in) over 20 days. In contrast, January experiences milder temperatures, with a minimum of 21°C (71°F) and a maximum of 28°C (82°F), averaging 25°C (77°F). The humidity drops to 65%, and precipitation is significantly lower at 66 mm (2.6 in) over 15 days. For a detailed look at January weather, visit Rio San Juan weather in January.
September and February present distinct weather patterns. In September, the temperatures are generally warmer, with minimums around 24°C (76°F), averages at 27°C (82°F), and maximums peaking at 31°C (88°F). This month also experiences significant rainfall, accumulating 145 mm (5.7 in) over 20 days, coupled with higher humidity levels at 73%.
Conversely, February is cooler, with temperatures ranging from a minimum of 21°C (69°F) to an average of 25°C (76°F) and maximums of 28°C (83°F). The precipitation in February is noticeably less, totalling 70 mm (2.7 in) over the same number of rainy days (20), and with lower humidity at 63%. For a detailed look at February weather, you can visit Rio San Juan weather in February.
September and March present notable differences in weather conditions. September tends to be warmer, with average temperatures ranging from 24°C (76°F) to a high of 31°C (88°F), while March sees slightly cooler averages, with temperatures from 21°C (71°F) to a maximum of 28°C (83°F). Additionally, September experiences more precipitation, totaling 145 mm (5.7 in) over 20 days, compared to March's 112 mm (4.4 in) across 18 days. The humidity in September is also higher at 73%, compared to a more comfortable 59% in March. For a more detailed look at March weather, you can check out Rio San Juan weather in March.
September and April showcase distinct weather patterns. In September, temperatures range from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), with an average of 27°C (82°F). The month sees significant rainfall, accumulating 145 mm (5.7 in) over 20 days, resulting in high humidity levels at 73%. In contrast, April offers milder conditions with a minimum temperature of 22°C (72°F) and a maximum of 29°C (84°F), averaging 25°C (78°F). Precipitation drops considerably to 68 mm (2.7 in) over 17 days, accompanied by a lower humidity of 58%. For more details on the weather in April, you can visit Rio San Juan weather in April.
September and May offer distinct weather experiences. September typically sees warmer temperatures, with a minimum of 24°C (76°F) and an average of 27°C (82°F), peaking at 31°C (88°F). In contrast, May is slightly cooler, with a minimum of 22°C (72°F), an average of 26°C (79°F), and a maximum of 30°C (86°F). September also brings significantly more rainfall, accumulating 145 mm (5.7 in) over 20 days, compared to May's 81 mm (3.2 in) across 19 days. Additionally, the humidity is higher in September at 73%, while May enjoys a more comfortable 57%. For a closer look at weather specifics in May, visit Rio San Juan weather in May.
When comparing the weather in September and June, both months display similar warm temperatures, with minimums around 24°C (76°F) and average highs of 27°C (82°F). However, September experiences a slightly hotter maximum temperature of 31°C (88°F), while June peaks at a milder 29°C (85°F). A notable difference lies in precipitation levels; September sees significantly higher rainfall, measuring 145 mm (5.7 in) across 20 days, compared to June's 60 mm (2.4 in) over 19 days. Additionally, September features higher humidity at 73%, contrasting with June's more comfortable 57%. For more detailed insights, check out Rio San Juan weather in June.
In September, temperatures are slightly warmer with a minimum of 24°C (76°F) and a maximum of 31°C (88°F), compared to July's temperatures which range from 24°C (76°F) to 30°C (87°F). Both months have similar average temperatures, around 27°C (81°F for July and 82°F for September). However, September experiences significantly more rainfall, with 145 mm (5.7 in) over 20 days, whereas July sees only 103 mm (4.1 in) across 23 days. Additionally, September's humidity is higher at 73%, compared to July's 63%. For a detailed look at July’s weather in this region, check out the link: Rio San Juan weather in July.
In comparing the weather of September and August, both months exhibit similar temperature ranges, with minimums at 24°C (76°F), averages of 27°C (82°F), and maximums reaching up to 31°C (88°F). However, September experiences significantly higher precipitation, totaling 145 mm (5.7 in) over 20 days, compared to August's 99 mm (3.9 in) over 22 days. Additionally, humidity levels are slightly higher in September at 73%, compared to 71% in August. For those looking for more information on August weather in the area, visit Rio San Juan weather in August.
In September, the weather is marked by slightly higher temperatures, with an average of 27°C (82°F) and maximums reaching 31°C (88°F). The month experiences considerable rainfall, totaling 145 mm (5.7 in) over approximately 20 days, along with a humidity level of 73%. In contrast, October sees a slight drop in maximum temperature to 30°C (87°F) and maintains a similar minimum temperature and average. Precipitation decreases to 102 mm (4.0 in) but is noted over a greater number of days, around 22, while humidity remains relatively stable at 72%. Overall, October offers a marginally cooler and drier climate compared to September. For more detailed information, you can visit Rio San Juan weather in October.
September and November in Rio San Juan exhibit similar warm conditions, with September featuring slightly higher average temperatures. In September, the minimum temperature is around 24°C (76°F), averaging 27°C (82°F) and peaking at 31°C (88°F), while November sees a minimum of 24°C (75°F), an average of 26°C (80°F), and a maximum of 30°C (86°F). Precipitation is more prevalent in September, with 145 mm (5.7 in) falling over 20 days, compared to November's 110 mm (4.3 in) over 21 days. Both months maintain relatively high humidity levels, hovering around 73% in September and slightly lower at 72% in November. For more details on November weather, you can check Rio San Juan weather in November.
In comparing the weather between September and December, we find that both months experience warm temperatures, but December tends to be slightly cooler. September's temperatures range from a minimum of 24°C (76°F) to a maximum of 31°C (88°F), with an average of 27°C (82°F). In contrast, December sees a lower temperature range, with minima at 23°C (74°F) and maxima at 29°C (85°F), averaging around 25°C (78°F).
Precipitation levels also differ significantly, as September experiences heavier rainfall with 145 mm (5.7 in) over 20 days, while December has only 83 mm (3.3 in) over 22 days, indicating a drier climate. Additionally, humidity is slightly lower in December at 69%, compared to September’s 73%. For more detailed insights on the weather patterns, check out this link: Rio San Juan weather in December.
As September unfolds in Rio San Juan, the weather takes on a unique character, distinct from the earlier summer months. With an average temperature hovering around a comfortable 27°C (82°F), the heat is tempered by elevated humidity levels of 73%, creating a warm, sticky atmosphere. Rainfall becomes a frequent companion, with 20 days marked by precipitation, contributing to a total of 145 mm (5.7 in) for the month. This increased rainfall not only adds to the lush landscape but also brings a refreshing change to the typical dryness of the preceding months. For a comprehensive overview of how Rio San Juan's weather patterns evolve throughout the year, visit Rio San Juan Climate.