Buenos Aires Weather in September

Buenos Aires in September sees pleasant temperatures, with highs around 20°C (68°F) and overnight lows of 9°C (48°F). Rainfall is fairly high at around 76 mm (3 in) on average, so pack waterproofs just in case.

Rainfall in Buenos Aires in September

You can expect rain on around 7 days based on historical patterns, with 76 mm (3 in) average for the month. Rainfall tends to arrive in short, intense showers this month. Rain days are few, but the showers can be surprisingly heavy.

Temperature in Buenos Aires in September

Buenos Aires has perfect weather in September, with days reaching 20°C (68°F) and nights cooling to 9°C (48°F). Conditions are often most pleasant around the middle of the day. Nights drop to 9°C (48°F). Cold nights like these are actually great for sleeping well, as long as you have a warm enough duvet.

Sunshine in Buenos Aires in September

The city usually sees around 186 hours of sunlight, indicating a moderately sunny period.

Wind Speed in Buenos Aires in September

Wind speeds average 4 m/s (8 knots) during September. At this speed, expect moderate winds that can raise dust and move small branches. Since this is an average, some days have gentle light winds while others experience stronger breezes that are quite noticeable.

Average water temperature in September

With water temperatures around 12°C (54°F), swimming isn't really an option for most visitors. The cold sets in quickly and a wetsuit won't fully solve it.

If you're inclined towards comfortable temperatures and drier conditions, September is a good time to visit Buenos Aires.

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For a detailed overview over the year and the best time to visit Argentina, check out our Buenos Aires's climate page.

Buenos Aires Temperature in September

Min Temperature 9°C (48°F)  

Max Temperature 20°C (68°F)  

Water Temperature 12°C (54°F)  

Chance of Rain 23%  

Precipitation 76 mm (3 in)  

Rainy days 7 days  

Humidity 70%  

Windspeed 4 m/s (8 knots)  

Sunshine 186 hours  

Percentage Sunshine  

Daily Historical Temperatures

50-year average (1976-2025)

Based on our historical records, temperatures in Buenos Aires typically rise from around 17°C (63°F) at the start of September to approximately 20°C (68°F) by the end. Nights are cool, with lows typically ranging from 7°C (45°F) to 11°C (52°F).

Average temperatures in September

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Daily Historical Precipitation

50-year average (1976-2025)

Average daily rainfall for each day of the month based on long-term records.

Average precipitation in September

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Historical weather for Buenos Aires in September

Browse day-by-day weather records for Buenos Aires spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Historical weather Temperatures Precipitation

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Buenos Aires historical weather extremes in September

Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Buenos Aires.

• On September 10, 2013, temperatures climbed to 34°C (93°F), marking the warmest September day on record.
• On September 6, 2008, Buenos Aires saw its coldest September day with temperatures maxing out at 7°C (45°F).
• Buenos Aires registered its coldest September night on September 1, 1990, with temperatures dropping to -3°C (27°F).

What to Wear in Buenos Aires in September

Comfortable temperatures call for an easy wardrobe in September. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. Wet weather is likely, so pack waterproof gear for multiple rainy days. With water temperatures around 12°C (54°F), the water is quite cold for swimming. You can skip the swimwear unless you're particularly tough. Sunglasses could come in handy during the sunnier parts of your trip.

What To Do in Buenos Aires in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

6/10

Cycling

9/10

Walking

9/10

Camping

4/10

Outdoor sports

9/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Argentina, check out our Buenos Aires's climate page.

More climate data for Buenos Aires

Temperature Rainfall Sunshine Humidity Wind Speed Water Temp

See the full Buenos Aires climate overview or explore weather in Argentina.