Month guide · Olhão, Portugal

Olhão in September: weather and what to expect

In September, Olhão averages highs of 26°C and lows of 19°C, with about 3 rainy days and 22 mm of rain. Highs are 3°C cooler than in August and 4°C warmer than in October. Crowds in the Algarve are medium.

Based on 1991-2020 climate data · Updated 1 November 2026 · Sources

Average high Town-level26°CLow 19°C
Sea temperature Modelled21°COpen sea nearby, average for the month
Rainy days Town-level322 mm in total
UV index Modelled7High at noon on a clear day
Crowds RegionalMediumThe Algarve as a whole

Is September a good time to visit?

Good for

No verdicts for Olhão 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 1991-2020
Usual range (8 in 10 years)Typical high

Highs fall about 3°C over the month. A day above 30°C happens in roughly 1 September in 2; nights below 15°C in about 1 in 6.

September in detail

Town-level · ERA5-Land
MeasureAugustSeptemberOctober
Average high29°C26°C23°C
Average low21°C19°C17°C
Rainy days (at least 1 mm)037
Total rainfall3 mm22 mm69 mm
Daylight (mid-month)13 h 37 min12 h 29 min11 h 18 min

Crowds, holidays and daylight

Visitor level RegionalMediumNights booked through online platforms in the Algarve in September 2025: about 55% of the busiest month.

Public holidays in September 2027

No national or regional public holidays.

Local (municipal) holidays are not included.

Daylight mid-month Exact12 h 29 minSunrise to sunset, calculated from the town's coordinates.
PlaceHighRain daysFrom Olhão
Altura, Algarve29°C334 km
Manta Rota, Algarve28°C333 km
Cabanas de Tavira, Algarve28°C424 km
Vila Nova de Cacela, Algarve28°C332 km
Conceição, Algarve28°C425 km

The nearest towns with a warmer September. Distances are in a straight line.

How September is changing

Town-level · ERA5-Land

September highs are 1.1°C warmer than in 1991-2000, and September rainfall is down about 35% (2016-2025 against 1991-2000). Days above 30°C in September went from 1.5 to 2.4 a year on average.

Questions about Olhão in September

How warm is Olhão in September?

Average highs are 26°C and lows 19°C. August averages 29°C and October 23°C.

Does it rain much in Olhão in September?

About 3 days have at least 1 mm of rain, with 22 mm in total over the month.

Is Olhão busy in September?

In September 2025, nights booked through online platforms in the Algarve were about 55% 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 Olhão 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