Santiago Weather in September
September in Santiago averages 18°C (64°F) during the day and 5°C (41°F) at night. Quite a bit of rainfall is typical this month, with around 72 mm (2.8 in) on average. An umbrella is a good idea.
Rainfall in Santiago in September
Historically, the month has about 4 days of rain, averaging 72 mm (2.8 in) in total. Although rain is not especially frequent, individual showers can still be quite heavy.
Temperature in Santiago in September
Daytime highs in Santiago in September reach 18°C (64°F), with nights around 5°C (41°F). A light jacket or extra layer can be useful, especially outside the warmest hours of the day. With lows around 5°C (41°F), nights are cold. The upside is that cool, crisp nights are often the best for a deep sleep.
Sunshine in Santiago in September
The month brings about 186 hours of sunlight, offering a comfortable mix of sun and overcast.Should you favor a climate that's both dry and comfortably warm, January, February, March, April, October, November and December typically offer the most agreeable circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Chile, check out our Santiago's climate page.
Santiago Temperature in September
Min Temperature
5°C (41°F)
Max Temperature
18°C (64°F)
Chance of Rain
12%
Precipitation
72 mm (2.8 in)
Rainy days
4 days
Humidity
76%
Sunshine
186 hours
Percentage Sunshine
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Santiago typically stay consistent throughout September, with daily highs averaging around 18°C (64°F). Nights are cold, with lows typically ranging from 5°C (41°F) to 7°C (45°F).
Average temperatures in September
Historical weather for Santiago in September
Browse day-by-day weather records for Santiago spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Santiago historical weather extremes in September
Based on 32 years of weather observations in Santiago between 1993 and 2025, these are the recorded extremes.
- The hottest September day on record in Santiago reached 32°C (90°F) (September 24, 2021).
- The lowest daytime temperature in September was 8°C (46°F), recorded on September 7, 1999.
- Nighttime temperatures dropped to -2°C (28°F) on September 3, 1996, marking the coldest September night on record.
Best Places in Chile in September
Find out more about the weather in Chile and which places have the best travel conditions in this month. See all of Chile in September →
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What to Wear in Santiago in September
For Santiago in September, you'll want flexible clothing. It's wise to pack cotton shirts, comfortable shorts, and a pair of jeans for cooler evenings. A light sweater or jacket is useful for air-conditioned spaces (like buses) or unexpected cool moments. Rain is likely on several days, so bring a good rain jacket. Sunglasses could come in handy during the sunnier parts of your trip.What To Do in Santiago 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 Chile, check out our Santiago's climate page.
Temperature Rainfall Sunshine Humidity
See the full Santiago climate overview or explore weather in Chile.
