Month guide · Sines, Portugal
Sines in September: weather and what to expect
In September, Sines averages highs of 24°C and lows of 17°C, with about 4 rainy days and 28 mm of rain. Highs are 2°C cooler than in August and 3°C warmer than in October. Our rules rate it good for walking and cycling. Crowds in the Alentejo are medium.
Is September a good time to visit?
Good for
- Walking and cyclingHighs of 24°C with about 4 rainy days
Not ideal for
Nothing stands out as a weaker fit.
Daily highs through September
Town-level · ERA5-Land 1991-2020Highs fall about 2°C over the month. A day above 30°C happens in roughly 1 September in 3.
September in detail
Town-level · ERA5-LandCrowds, holidays and daylight
Public holidays in September 2027
No national or regional public holidays.
Local (municipal) holidays are not included.
Warmer in September
Where is warm in September →| Place | High | Rain days | From Sines |
|---|---|---|---|
| Ferreira do Alentejo, Alentejo | 29°C | 4 | 67 km |
| Ermidas, Alentejo | 28°C | 4 | 43 km |
| Aljustrel, Alentejo | 28°C | 4 | 62 km |
| Castro Verde, Alentejo | 28°C | 4 | 75 km |
| Odemira, Alentejo | 27°C | 4 | 45 km |
The nearest towns with a warmer September. Distances are in a straight line.
How September is changing
Town-level · ERA5-LandSeptember highs are 1.3°C warmer than in 1991-2000, and September rainfall is down about 40% (2016-2025 against 1991-2000). Days above 25°C in September went from 8.0 to 12 a year on average.
Questions about Sines in September
Is September a good time to visit Sines?
Our rules rate September good for walking and cycling (highs of 24°C with about 4 rainy days).
How warm is Sines in September?
Average highs are 24°C and lows 17°C. August averages 26°C and October 22°C.
Does it rain much in Sines in September?
About 4 days have at least 1 mm of rain, with 28 mm in total over the month.
Is Sines busy in September?
In September 2025, nights booked through online platforms in the Alentejo were about 50% of the busiest month, which we count as medium. The figure is for the whole region and leaves out hotels.
How long are the days in Sines in September?
About 12 h 29 min from sunrise to sunset in the middle of the month.
Sources
Climate: ERA5-Land, Copernicus Climate Change Service (C3S) Climate Data Store, contains modified Copernicus information (CC BY 4.0). Crowds: Eurostat, nights spent in short-stay accommodation booked through online platforms (tour_ce_omn12) (CC BY 4.0). Place names and populations: GeoNames (CC BY 4.0). Climate averages cover 1991-2020. Daylight: calculated from the town's coordinates. Full methodology