Month guide · Santiago do Cacém, Portugal

Santiago do Cacém in December: weather and what to expect

In December, Santiago do Cacém averages highs of 15°C and lows of 8°C, with about 10 rainy days and 76 mm of rain. Highs are 2°C cooler than in November and 1°C warmer than in January. Crowds in the Alentejo are low.

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

Average high Town-level15°CLow 8°C
Rainy days Town-level1076 mm in total
UV index Modelled2Low at noon on a clear day
Crowds RegionalLowThe Alentejo as a whole

Is December a good time to visit?

Good for

No verdicts for Santiago do Cacém in December 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 December

Town-level · ERA5-Land 1991-2020
Usual range (8 in 10 years)Typical high

Highs fall about 1°C over the month. A day above 20°C happens in roughly 1 December in 6.

December in detail

Town-level · ERA5-Land
MeasureNovemberDecemberJanuary
Average high17°C15°C14°C
Average low11°C8°C7°C
Rainy days (at least 1 mm)10109
Total rainfall77 mm76 mm63 mm
Daylight (mid-month)10 h 09 min9 h 33 min9 h 48 min

Crowds, holidays and daylight

Visitor level RegionalLowNights booked through online platforms in the Alentejo in December 2025: about 15% of the busiest month.

Public holidays in December 2026

  • 1 Dec Restoration of Independence Day
  • 8 Dec Immaculate Conception
  • 25 Dec Christmas Day

Local (municipal) holidays are not included.

Daylight mid-month Exact9 h 33 minSunrise to sunset, calculated from the town's coordinates.
PlaceHighRain daysFrom Santiago do Cacém
Aljezur, Algarve16°C1078 km
São Marcos da Serra, Algarve16°C978 km
Odemira, Alentejo16°C947 km
São Bartolomeu de Messines, Algarve16°C892 km
Vila Nova de Milfontes, Alentejo16°C1034 km

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

How December is changing

Town-level · ERA5-Land

December highs are 0.8°C warmer than in 1991-2000, and December rainfall is down about 35% (2016-2025 against 1991-2000).

Questions about Santiago do Cacém in December

How warm is Santiago do Cacém in December?

Average highs are 15°C and lows 8°C. November averages 17°C and January 14°C.

Does it rain much in Santiago do Cacém in December?

About 10 days have at least 1 mm of rain, with 76 mm in total over the month.

Is Santiago do Cacém busy in December?

In December 2025, nights booked through online platforms in the Alentejo were about 15% of the busiest month, which we count as low. The figure is for the whole region and leaves out hotels.

How long are the days in Santiago do Cacém in December?

About 9 h 33 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