Middle of the wetter season · Weather & things to do
Old San Juan in August
Old San Juan's warmest month brings highs averaging 87°F (30°C), lows of 80°F (27°C) and about 5.1 in (130 mm) of rain.
With a comfort score of 57/100 (10th of 12), it's one of the toughest months, held back mainly by cloud cover.
- Avg high
- 87°F (30°C)
- Avg low
- 80°F (27°C)
- Rain
- 5.1 in (130 mm)
- Humidity
- 79%
- Cloud cover
- 66%
- Daylight
- ~12 h 38 min
- Comfort score
- 57/100 · Fair
What August feels like
Expect proper heat: afternoons average 87°F (30°C), so plan walking and hiking for the morning and save midday for shade, lunch or a swim.
Even at night it stays warm, around 80°F (27°C).
Humidity averages 79%, so the air feels sticky and the heat feels stronger than the thermometer says.
Rain is a real factor, with about 5.1 in (130 mm) across the month.
Plan around August
August is one of the lower-scoring months here; the best are December – March.
- Comfort slips from 61/100 in July to 57/100.
- Our Old San Juan & Ponce route is planned for Dec – mid-Jan, a window set by the holiday season rather than the weather — August falls outside it.
What to pack for August
- Light, breathable clothes87°F afternoons
- Sunscreen, sunglasses and a hathigh UV on clear days
- Refillable water bottleeasy to dehydrate in the heat
- Quick-dry fabrics79% average humidity
- Rain jacket and waterproof shoes5.1 in of rain on average
- Comfortable walking shoesmost picks involve some walking
What to do in Old San Juan in August
With 5.1 in of rain, these picks lean toward food, drink and places with a roof, with outdoor options when the weather breaks.
La Factoria
Unsigned cocktail bar of linked rooms on Calle San Sebastian, with salsa dancing late into the night.
Why now A sit-down stop to wait out showers in a month with 5.1 in of rain.
Casa Cortes ChocoBar
Cafe run by the Cortes chocolate family, serving hot chocolate with cheese, chocolate dishes and breakfast.
Why now Easy to slot in when August's rain moves in.
Catedral de San Juan Bautista
One of the oldest cathedrals in the Americas, rebuilt in the 1800s, holding the tomb of Juan Ponce de Leon.
Castillo San Felipe del Morro
Six-level Spanish citadel begun in 1539 on the headland guarding San Juan Bay, part of a UNESCO World Heritage Site.
Paseo de la Princesa
Tree-lined 19th-century promenade along the bay under the city walls, ending at the Raices fountain.
Why now Go early — afternoons average 87°F.
Nearby in August
- Ponce in August~46 mi · highs 88°F, 3.8 in rain · similar daytime temperatures, drier
NASA POWER 2001–2025 monthly averages on a ~50 km grid. Comfort scores weigh temperature, rain, humidity and cloud: see how we score each month. Check a forecast before you go.
Old San Juan in August: quick answers
Is August a good time to visit Old San Juan?
It's one of the tougher months here, scoring 57/100, held back mainly by cloud cover. The best months are December – March. Expect highs of 87°F (30°C) and 5.1 in (130 mm) of rain.
How hot is Old San Juan in August?
Average highs are 87°F (30°C) and average lows 80°F (27°C), making it the warmest month by daytime highs.
Does it rain a lot in Old San Juan in August?
Yes: about 5.1 in (130 mm) of rain falls across August on average, the 4th-wettest month of the year. The annual total is about 47.5 in (1207 mm).
What should I pack for Old San Juan in August?
Bring light, breathable clothes (87°F afternoons), sunscreen, sunglasses and a hat (high UV on clear days), refillable water bottle (easy to dehydrate in the heat), quick-dry fabrics (79% average humidity) and rain jacket and waterproof shoes (5.1 in of rain on average).
More on Old San Juan
Planning Old San Juan in August?
Share this August plan with your group, poll everyone on dates and keep the packing list in one place.