Month guide · Nisa, Portugal
Nisa in September: weather and what to expect
In September, Nisa averages highs of 27°C and lows of 16°C, with about 5 rainy days and 40 mm of rain. Highs are 4°C cooler than in August and 6°C warmer than in October. Crowds in the Alentejo are medium.
Is September a good time to visit?
Good for
No verdicts for Nisa in September yet. They only use climate values that are precise enough to judge with.
Not ideal for
Nothing stands out as a weaker fit.
Daily highs through September
Town-level · ERA5-Land 1991-2020Highs fall about 6°C over the month. A day above 35°C happens in roughly 1 September in 2.
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 Nisa |
|---|---|---|---|
| Ponte de Sôr, Alentejo | 29°C | 5 | 43 km |
| Pego, Oeste e Vale do Tejo | 28°C | 5 | 43 km |
| Vila Velha de Ródão, Centro | 28°C | 5 | 16 km |
| Alter do Chão, Alentejo | 28°C | 5 | 35 km |
| Atalaia, Alentejo | 27°C | 6 | 20 km |
The nearest towns with a warmer September. Distances are in a straight line.
How September is changing
Town-level · ERA5-LandSeptember highs are 2.3°C warmer than in 1991-2000, and September rainfall is down about 15% (2016-2025 against 1991-2000). Days above 30°C in September went from 6.8 to 9.9 a year on average.
Questions about Nisa in September
How warm is Nisa in September?
Average highs are 27°C and lows 16°C. August averages 32°C and October 22°C.
Does it rain much in Nisa in September?
About 5 days have at least 1 mm of rain, with 40 mm in total over the month.
Is Nisa 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 Nisa in September?
About 12 h 31 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