Porto Alegre in September
In September, Porto Alegre averages 22°C (72°F) during the day and 14°C (57°F) at night, with frequent rain — about 17 days of the month see precipitation (170 mm total).
ShoulderConditions are comfortable for sightseeing without being sweltering. Expect daily rain or showers, often in heavy bursts.
September offers comfortable temperatures in Porto Alegre, with some rain to plan around.
How September compares to the rest of the year in Porto Alegre
September is in the middle of the year for warmth in Porto Alegre (8th of 12) and moderately rainy compared to the rest of the year (5th of 12). Daytime temperature runs 2°C below the annual average (25°C). September runs 1°C warmer than August (21°C) and warms a further 2°C into October (24°C).
September sunrise & sunset in Porto Alegre
Times shown for Porto Alegre local time (America/Sao_Paulo), calculated for the 15th of September. They shift by a few minutes day to day across the month.
Photography light in Porto Alegre — September
Golden-hour and blue-hour windows for the 15th of September, in Porto Alegre's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).
📅 When to book — Porto Alegre in September
Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on September's tier (Shoulder) and Porto Alegre's popularity.
Crowds & pricing — September in Porto Alegre
Porto Alegre is in a shoulder season month — fewer crowds, slightly lower prices, and a calmer atmosphere than peak weeks. Most major sights stay open with normal hours, though a handful of seasonal restaurants or boat trips may run reduced schedules. Many regulars consider these months the best time to visit because you trade a small amount of weather reliability for a much more pleasant on-the-ground experience.
Why this tier: comfortable tourism weather
Sun & mosquito risk — September in Porto Alegre
UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.
Porto Alegre in other months
| Month | Avg high | Avg low | Rainfall | Rain days | Snow days |
|---|---|---|---|---|---|
| January | 31°C / 87°F | 21°C / 71°F | 116 mm | 21 | — |
| February | 30°C / 86°F | 21°C / 69°F | 89 mm | 18 | — |
| March | 28°C / 82°F | 20°C / 67°F | 125 mm | 20 | — |
| April | 25°C / 78°F | 17°C / 63°F | 75 mm | 16 | — |
| May | 21°C / 70°F | 13°C / 56°F | 150 mm | 15 | — |
| June | 19°C / 66°F | 11°C / 52°F | 145 mm | 13 | — |
| July | 20°C / 67°F | 11°C / 51°F | 136 mm | 13 | — |
| August | 21°C / 70°F | 12°C / 53°F | 104 mm | 13 | — |
| September | 22°C / 72°F | 14°C / 57°F | 170 mm | 17 | — |
| October | 24°C / 75°F | 16°C / 60°F | 155 mm | 19 | — |
| November | 26°C / 80°F | 17°C / 62°F | 126 mm | 16 | — |
| December | 29°C / 85°F | 20°C / 67°F | 113 mm | 17 | — |
Other cities with similar September weather
🌍 See the full ranked list of climate twins for Porto Alegre in September →
Frequently asked questions
How hot is Porto Alegre in September?
In September, Porto Alegre averages a high of 22°C (72°F) and a low of 14°C (57°F) — generally mild and pleasant.
Does it rain a lot in Porto Alegre in September?
September is quite rainy in Porto Alegre, with about 17 rainy days on average.
Is September a good time to visit Porto Alegre?
September is mild and pleasant but on the rainy side. It suits travelers who are comfortable with mild and pleasant weather; check the month-by-month ranking to compare it against the rest of the year.
What should I pack for Porto Alegre in September?
Pack light layers for warm days and cooler evenings, plus a compact umbrella or rain jacket. See the full September packing list for Porto Alegre for a complete, climate-based checklist.
Check the live 10-day forecast and sunrise/sunset.