Month guide · Castro Marim, Portugal
Castro Marim in May: weather and what to expect
In May, Castro Marim averages highs of 25°C and lows of 15°C, with about 5 rainy days and 30 mm of rain. Highs are 3°C warmer than in April and 5°C cooler than in June. Our rules rate it good for walking and cycling. Crowds in the Algarve are medium.
Is May a good time to visit?
Good for
- Walking and cyclingHighs of 25°C with about 5 rainy days
Not ideal for
Nothing stands out as a weaker fit.
Daily highs through May
Town-level · ERA5-Land 1991-2020Highs climb about 4°C over the month.
May in detail
Town-level · ERA5-LandCrowds, holidays and daylight
Public holidays in May 2027
- 1 May Labor Day
- 27 May Corpus Christi
Local (municipal) holidays are not included.
Warmer in May
Where is warm in May →| Place | High | Rain days | From Castro Marim |
|---|---|---|---|
| Mértola, Alentejo | 26°C | 7 | 51 km |
| Minas de São Domingos, Alentejo | 25°C | 7 | 51 km |
| Neves, Alentejo | 25°C | 7 | 95 km |
The nearest towns with a warmer May. Distances are in a straight line.
How May is changing
Town-level · ERA5-LandMay highs are 2.3°C warmer than in 1991-2000, and May rainfall is down about 30% (2016-2025 against 1991-2000). Days above 30°C in May went from 2.5 to 6.1 a year on average.
Questions about Castro Marim in May
Is May a good time to visit Castro Marim?
Our rules rate May good for walking and cycling (highs of 25°C with about 5 rainy days).
How warm is Castro Marim in May?
Average highs are 25°C and lows 15°C. April averages 21°C and June 29°C.
Does it rain much in Castro Marim in May?
About 5 days have at least 1 mm of rain, with 30 mm in total over the month.
Is Castro Marim busy in May?
In May 2025, nights booked through online platforms in the Algarve were about 40% 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 Castro Marim in May?
About 14 h 08 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