Guanica Weather in September
Thinking of visiting Guanica in September? Expect very high temperatures reaching 30°C (86°F) during the day, dropping to 25°C (77°F) at night, and be prepared for the wettest month of the year.
Rainfall in Guanica in September
The month brings the most rain, so be prepared with an umbrella for the occasional shower. Typically around 17 days of rainfall are expected, averaging 132 mm (5.2 in) for the month. Wet weather is a regular and significant part of this month. Frequent days of rain combined with high totals means proper waterproofs are worth packing.
Temperature in Guanica in September
Temperatures in Guanica in September top out at 30°C (86°F) and drop to 25°C (77°F) overnight. It's usually most comfortable outside during the morning and later in the day. Nights stay warm at around 25°C (77°F), so light bedding and good ventilation are worth thinking about.If you prefer dry days with pleasant temperatures, September may not be the ideal month to visit Guanica. Our weather planner can help you explore destinations with more pleasant weather conditions.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Puerto Rico, check out our Guanica's climate page.
Guanica Temperature in September
Daily Historical Temperatures
48-year average (1977-2025)
Based on our historical records, temperatures in Guanica typically stay consistent throughout September, with daily highs averaging around 30°C (86°F). Nights are warm, with lows around 24°C (75°F).
Average temperatures in September
Historical weather for Guanica in September
Browse day-by-day weather records for Guanica spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Guanica historical weather extremes in September
Based on weather observations in Guanica between 1999 and 2025, these are the recorded extremes during September.
- The hottest September day on record in Guanica reached 35°C (95°F) (September 3, 2024).
- The coldest September day was on September 18, 2022, with a maximum of 27°C (81°F).
- Guanica registered its coldest September night on September 22, 2002, with temperatures dropping to 21°C (70°F).
Best Places in Puerto Rico in September
Find out more about the weather in Puerto Rico and which places have the best travel conditions in this month. See all of Puerto Rico in September →
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What to Wear in Guanica in September
Warm weather calls for comfortable, breathable clothing in September. Cotton t-shirts, shorts, light dresses, and sandals are perfect. You might still want a light layer for evenings or air-conditioned places (for example buses). High rain levels are expected, so pack waterproof gear and an umbrella or poncho.What To Do in Guanica 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 Puerto Rico, check out our Guanica's climate page.
See the full Guanica climate overview or explore weather in Puerto Rico.