Weather in San Francisco in September
San Francisco, Costa Rica averages a high of 24.2°C (75.6°F) and low of 17.7°C (63.9°F) in September, with 27 rain days and 7.6 hours of daily sunshine. Travel score: 62.2/100 (Good). The best time to visit San Francisco is February.
High
24°C76°F
Low
18°C64°F
🌧️
27
rain days
☀️
7.6
hrs/day sunshine
💧
92%
humidity
62— Good
September in San Francisco is warm and very rainy — pack an umbrella and enjoy indoor attractions too.
What are the average temperatures in San Francisco?
How much does it rain in San Francisco in September?
San Francisco receives an average of 390mm of rainfall across 27 rainy days in September. The annual total is 2555.2mm.
What should I pack for San Francisco in September?
Essentials
👟
Comfortable walking shoes
Essential for exploring the city
👕
Light layers and t-shirts
Warm weather around 24°C
🧥
Waterproof jacket
Frequent rain expected (27 rainy days)
☔
Umbrella
Essential for the rainy season
👢
Waterproof shoes
Keep your feet dry in wet conditions
🧴
Sunscreen SPF 30+
8 hours of sunshine daily
🕶️
Sunglasses
Protect your eyes from bright sun
🎉Visiting Costa Rica in September?
Don't miss any public holidays — check before you book!
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Data based on 1994–2024 averages · Last updated: 2024-12-31