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Merlo Weather in September
Merlo in September averages 21°C (70°F) during the day and 6°C (43°F) at night. Some rainfall is typical for this time of year.
Rainfall in Merlo in September
Typically, you can expect about 4 days of rain this month, with 35 mm (1.4 in) on average. Rainfall tends to arrive in short, intense showers this month. Rain days are few, but the showers can be surprisingly heavy.
Temperature in Merlo in September
If you're visiting Merlo in September, expect excellent temperatures with highs of 21°C (70°F) and overnight lows of 6°C (43°F). A light jacket or extra layer can be useful, especially outside the warmest hours of the day. With overnight lows of 6°C (43°F), nights are cold. The cold air does make for deep, comfortable sleep if you have enough blankets.If you're a fan of comfortable temperatures and drier conditions, September is a great time to visit.
Merlo Temperature in September
Min Temperature
6°C (43°F)
Max Temperature
21°C (70°F)
Chance of Rain
13%
Precipitation
35 mm (1.4 in)
Rainy days
4 days
Merlo Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Merlo - and find the best time to visit.
Daily Historical Temperatures
48-year average (1976-2025)
Based on our historical records, temperatures in Merlo typically rise from around 21°C (70°F) at the start of September to approximately 25°C (77°F) by the end. Nights are cool, with lows typically ranging from 6°C (43°F) to 12°C (54°F).
Average temperatures in September
Daily Historical Precipitation
48-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather records for Merlo in September
Browse day-by-day weather records for Merlo spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Merlo historical weather extremes in September
Based on 27 years of weather observations in Merlo between 1999 and 2026, these are the recorded extremes.
- On September 28, 2011, temperatures climbed to 36°C (97°F), marking the warmest September day on record.
- The lowest daytime temperature in September was 6°C (43°F), recorded on September 3, 2010.
- Nighttime temperatures dropped to -5°C (23°F) on September 10, 2022, marking the coldest September night on record.
Best Places in Argentina in September
Find out more about the weather in Argentina and which places have the best travel conditions in this month. See all of Argentina in September →
perfect weather
pleasant
tolerable
unpleasant
poor
Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).
What to Wear in Merlo in September
For Merlo 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. Some rain is possible, so pack something to handle light showers.
What To Do in Merlo in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
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Cycling10/10 -
Walking10/10 -
Camping5/10 -
Outdoor sports10/10
Merlo 3-Day Forecast
More climate data for Merlo
See the full Merlo climate overview or explore weather in Argentina.
Popular in September
Where to go in September - average daytime high across popular destinations.
Córdoba
23°C (73°F) Salta21°C (70°F) Mendoza20°C (68°F) Buenos Aires
20°C (68°F) Mar del Plata16°C (61°F) San Martín de los Andes
8°C (46°F) San Carlos de Bariloche8°C (46°F) Bucket list
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