Río San Juan Weather in September
During September, Río San Juan experiences very high daytime temperatures of 31°C (88°F) and cooler nights around 25°C (77°F). Expect quite a bit of rainfall. Around 124 mm (4.9 in) is typical.
Rainfall in Río San Juan in September
Climate statistics over the past 30 years suggest around 16 days of rain, with 124 mm (4.9 in) average for the month. This is a wet month with frequent and often heavy showers. Both the number of rain days and the total rainfall are high.
Temperature in Río San Juan in September
In September, expect very high temperatures in Río San Juan, with highs of 31°C (88°F) and lows of 25°C (77°F) at night. If you're spending a lot of time outdoors, it helps to plan around the warmer part of the day. With overnight lows of 25°C (77°F), evenings and nights remain warm. Light clothing and an open window or fan can help you sleep comfortably. Keep in mind, these temperatures are averages, and some days might be even warmer. Dress suitably to manage the heat.Our weather planner can help you find worldwide destinations with pleasant weather during this period. January, February and March typically offer the best weather for Río San Juan.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the Dominican Republic, check out our Río San Juan's climate page.
Río San Juan Temperature in September
Min Temperature
25°C (77°F)
Max Temperature
31°C (88°F)
Chance of Rain
52%
Precipitation
124 mm (4.9 in)
Rainy days
16 days
Humidity
78% *
Daily Historical Temperatures
47-year average (1976-2025)
Based on our historical records, temperatures in Río San Juan typically stay consistent throughout September, with daily highs averaging around 31°C (88°F). Nights are warm, with lows around 24°C (75°F).
Average temperatures in September
Daily Historical Precipitation
47-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Río San Juan in September
Browse day-by-day weather records for Río San Juan spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Río San Juan historical weather extremes in September
Based on 26 years of weather observations (1999-2025), these are the most extreme conditions recorded in Río San Juan.
- The warmest day in September was on September 15, 2024, with a maximum of 36°C (97°F).
- Río San Juan experienced its chilliest September day on September 19, 2022, reaching only 25°C (77°F).
- Río San Juan registered its coldest September night on September 27, 2018, with temperatures dropping to 19°C (66°F).
Best Places in the Dominican Republic in September
Find out more about the weather in the Dominican Republic and which places have the best travel conditions in this month. See all of the Dominican Republic in September →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Río San Juan in September
Warm but pleasant conditions in Río San Juan in September. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. Expect heavy rainfall, so bring good rain protection and waterproof bags.What To Do in Río San Juan in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the Dominican Republic, check out our Río San Juan's climate page.
See the full Río San Juan climate overview or explore weather in the Dominican Republic.
