San Jose Weather in September
Costa Rica · 30-year monthly averages
🤔 Fair time to visit
September in San Jose is warm, with average daytime highs around 30°C (86°F) and nighttime lows near 17°C (62°F). Expect roughly 296mm of precipitation spread over about 22 rainy days, and heavy rainfall is common — this is peak wet season territory.
Avg high
30°C
86°F
Avg low
17°C
62°F
Rainfall
296mm
very wet
Rainy days
22
days with ≥1mm
🎒 What to pack
- light summer clothing
- sunscreen and sunglasses
- compact umbrella or rain jacket
September vs the rest of the year
FAQ
- How hot is San Jose in September?
- September in San Jose is warm, with average daytime highs around 30°C (86°F) and nighttime lows near 17°C (62°F). Expect roughly 296mm of precipitation spread over about 22 rainy days, and heavy rainfall is common — this is peak wet season territory.
- Does it rain a lot in San Jose in September?
- San Jose sees around 296mm of precipitation in September on average — very wet by global standards.
- Is September a good time to visit San Jose?
- September is a workable month to visit San Jose, but expect some weather trade-offs.