Data checked: October 2026
When should you come? It depends on the region — Porto in August is a different climate from Faro, and Madeira barely has a winter at all. Below, seven tables built from daily ERA5-Land reanalysis data (2015–2024) and monthly sea-surface normals from the Open-Meteo Marine model, with short data-driven takeaways for each region.
Warmest month: Aug (29.3°C). Driest: Aug (0 mm). Warmest sea: Oct (19.5°C).
Warmest month: Aug (28.4°C). Driest: Aug (1 mm). Warmest sea: Oct (18.4°C).
Warmest month: Aug (24.8°C). Driest: Jul (13 mm). Warmest sea: Oct (18.3°C).
Warmest month: Aug (33.1°C). Driest: Jul (3 mm). Warmest sea: Oct (19.3°C).
Warmest month: Aug (29°C). Driest: Jul (10 mm). Warmest sea: Oct (18.3°C).
Warmest month: Aug (26.6°C). Driest: Aug (12 mm). Warmest sea: Aug (24.9°C).
Warmest month: Aug (24.9°C). Driest: Jul (45 mm). Warmest sea: Aug (24.6°C).
How to read these tables
Air temperatures are 2015–2024 monthly means of daily highs/lows at each region’s representative station (ERA5-Land via Open-Meteo, CC BY 4.0). Rainy days count days with ≥1 mm in a typical month. Sea temperatures are offshore surface values from the Open-Meteo Marine model (2023–2025) — beach shallows run warmer in summer. Mountain and valley microclimates (Douro, Serra da Estrela) vary beyond these station values.
Frequently asked questions
What is the best month to visit Portugal?
For most travellers, May–June and September–October: warm sea in the south, stable weather everywhere, thinner crowds and lower prices than July–August. For beach-first trips, August has the warmest sea in the Algarve (20–24°C); for cities and hiking, April–June and September–October are the most comfortable.
What is the rainy season in Portugal?
November–February on the northern coast (Porto averages 10–14 rainy days per month in winter) and December–February in Lisbon. The Algarve stays noticeably drier even in winter, and Madeira and the Azores see rain in every month — usually short and local.
When is the sea warmest in Portugal?
August–September everywhere. The eastern Algarve is the warmest stretch of mainland coast (22–24°C), the west coast around Lisbon and Nazaré runs 3–4°C cooler due to upwelling, and Madeira peaks around 24°C.
Is Portugal good to visit in winter?
Yes for cities, the Algarve and Madeira: daytime highs stay around 15–18°C in the south and 20°C+ on Madeira. The north is cooler and wetter. It is the low season — expect shorter opening hours on the coast but normal city life and easy reservations.