Porto Alegre · AutumnMonth summary
Porto Alegre weather in September
✅ Good
🌡️ Temperature min / max
14°C – 22°C
🌧 Rainy days
39% of days
☀️ Sunshine
9.1h per day on average
🌊 🌊 Season
Autumn
⭐ ⭐ Weather score
7.3/10
📅 📅 Best month
December (8.2/10)
Quick decision
Should you visit Porto Alegre in September?
✅ Good
✅ Yes if: you want shoulder-season value — fewer crowds, 22°C.
❌ No if: you need maximum sunshine — some overcast days are possible.
Our take: September is a good time to visit Porto Alegre. December remains slightly better (+0.9 pts).
By trip type
Porto Alegre in September by trip type
- 🏙️ 🏙️ City break / culture : ✅ Good
- 🚶 🚶 Outdoor activities : ⚠️ Possible
- 🏖️ Beach / swimming : — No sea access
- 💰 💰 Budget : ✅ Low season
Local context
What to expect in September
Autumn in Porto Alegre is often underrated: 22°C, golden light and declining crowds. An interesting window. Expect rain on 39% of days — a light raincoat in the bag is recommended. Not the best window, but acceptable if dates are constrained. December (8.2/10) is significantly better if possible.
Browse by month
All months for Porto Alegre
Annual table
Month-by-month comparison
| Month | Min °C | Max °C | Rain % | Precip mm | Sun h/d | Score |
|---|---|---|---|---|---|---|
| 🌤️ January | 21°C | 30°C | 41% | 3.2 | 12.6h | 7.8/10 |
| 🌤️ February | 21°C | 30°C | 37% | 3.0 | 12.6h | 7.9/10 |
| 🌤️ March | 20°C | 28°C | 37% | 3.9 | 11.0h | 8.1/10 |
| 🌤️ April | 18°C | 25°C | 31% | 3.3 | 10.3h | 7.8/10 |
| ⛅ May | 13°C | 21°C | 38% | 5.6 | 8.5h | 7.2/10 |
| 🌤️ June | 11°C | 19°C | 33% | 4.8 | 8.1h | 7.1/10 |
| 🌤️ July | 10°C | 19°C | 30% | 4.0 | 8.8h | 7.1/10 |
| 🌤️ August | 11°C | 21°C | 32% | 3.3 | 9.7h | 7.3/10 |
| 🌤️ September | 14°C | 22°C | 39% | 5.8 | 9.1h | 7.3/10 |
| 🌤️ October | 15°C | 24°C | 41% | 4.5 | 10.6h | 7.5/10 |
| 🌤️ November | 17°C | 26°C | 38% | 4.0 | 12.6h | 8.0/10 |
| 🌤️ December | 19°C | 29°C | 34% | 3.1 | 13.0h | 8.2/10 |
Ideal
Fair
Challenging climate
◀ Current month · Source Open-Meteo · 10 years
📊 Data source
Data based on 10 years of ERA5 records via Open-Meteo, with ECMWF seasonal adjustment. In September, Porto Alegre averages 22°C, 39% rainy days and 9.1h of sunshine per day. Overall weather score: 7.3/10.
See methodology →
Comparison
September vs December (best month)
The best month is December (score 8.2/10). Difference:
- 🌡️ Max temperature : +7°C
- 🌧 Rainy days : -5%
- ☀️ Sunshine : +3.9h/day
FAQ
FAQ — Porto Alegre in September
Is September a good time to visit Porto Alegre?
September is an acceptable time for Porto Alegre (score 7.3/10). Conditions are decent but not optimal — consider December (8.2/10) if possible.
What to do in Porto Alegre in September?
With 22°C max and 9.1h of sunshine, focus on cultural sites, museums and local gastronomy.
Accommodation
Find a place to stay in Porto Alegre
Find places to stay in Porto Alegre in September
Search on Hotels.com
Activities & tours
Activities and tours in Porto Alegre
Guided tours, skip-the-line tickets and local experiences.
Browse activities on GetYourGuide
Flights
Find a flight to Porto Alegre
Compare flights from all airlines.
Search flights
←
Explore also
Similar destinations in September
Uruguay🌍 Top destinations
Other top destinations in September
Puerto Escondido
Trinidad
Banjul
SantiagoWeather rankings
Compare destinations by weather
Best in EuropeGuides & comparisons