Porto Weather in September
In Porto, September brings high daytime temperatures around 24°C (75°F), with nights cooling to 17°C (63°F). Expect quite a bit of rainfall this month.
Rainfall in Porto in September
Looking at the last 30 years, the data shows about 9 days with rain, averaging 62 mm (2.4 in) for the month. Individual showers can be quite heavy this month. A proper umbrella or rain jacket is worth having.
Temperature in Porto in September
September is a perfect month in Porto, with 24°C (75°F) during the day and 17°C (63°F) at night. September is typically considered a summer month. Conditions stay fairly consistent through the month, making it easier to plan what to wear. With overnight lows of 17°C (63°F), evenings can feel noticeably cooler than the daytime. An extra layer is a good idea, though the cool air makes for a good night's sleep.
Sunshine in Porto in September
The city usually sees around 224 hours of sunlight, indicating many sunny days — a great month for sightseeing.
Wind Speed in Porto 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
At 18°C (64°F), the water is getting there — comfortable enough for most swimmers, though those used to warmer seas may still find it a touch cool.If you're a fan of comfortable temperatures and drier conditions, September is a great time to visit.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Portugal, check out our Porto's climate page.
Porto Temperature in September
Min Temperature
17°C (63°F)
Max Temperature
24°C (75°F)
Water Temperature
18°C (64°F)
Chance of Rain
29%
Precipitation
62 mm (2.4 in)
Rainy days
9 days
Humidity
76%
Windspeed
4 m/s (8 knots)
Sunshine
224 hours
Percentage Sunshine
64%
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Porto typically stay consistent throughout September, with daily highs averaging around 24°C (75°F). Nights are pleasant, with lows typically ranging from 13°C (55°F) to 15°C (59°F).
Average temperatures in September
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
Historical weather for Porto in September
Browse day-by-day weather records for Porto spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Porto historical weather extremes in September
Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Porto.
- Porto recorded its highest September temperature of 36°C (97°F) on September 12, 1978.
- On September 26, 2015, Porto saw its coldest September day with temperatures maxing out at 16°C (61°F).
- Porto registered its coldest September night on September 17, 2017, with temperatures dropping to 7°C (45°F).
Best Places in Portugal in September
Find out more about the weather in Portugal and which places have the best travel conditions in this month. See all of Portugal in September →
perfect weather
pleasant
tolerable
unpleasant
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What to Wear in Porto 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 18°C (64°F), the water is quite cold for swimming. You can skip the swimwear unless you're particularly tough. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.What To Do in Porto 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 Portugal, check out our Porto's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed Water Temp
See the full Porto climate overview or explore weather in Portugal.
