Spain and Portugal share the Iberian Peninsula, but their climates differ more than most people expect. Portugal’s long Atlantic coastline keeps it wetter and more temperate, while Spain’s larger landmass creates sharper extremes, from scorching interior summers to genuinely cold winters on the central plateau. The differences come down to ocean influence, geography, and size.
Why the Atlantic Makes Portugal Wetter
Portugal sits entirely on the Atlantic side of the peninsula, and that positioning defines its climate. Moisture-laden air rolls in off the ocean year-round, delivering significantly more rainfall than most of Spain receives. Porto averages 1,237 mm of rain per year, and Braga in the northwest gets nearly 1,449 mm. Even Lisbon, farther south, receives 774 mm annually. Compare that with Madrid at 423 mm or Seville at 539 mm. The only Spanish cities that come close to Portuguese rainfall totals are those in the northwest corner of Galicia, which shares Portugal’s Atlantic exposure.
Southern Portugal is the exception. The Algarve region, centered around Faro, gets only about 512 mm of rain per year, putting it closer to the drier parts of Spain. And southeastern Spain is remarkably arid: Almería averages just 200 mm annually, making it one of the driest places in Europe.
Humidity Along the Coast vs. the Interior
Portugal’s Atlantic orientation also makes it noticeably more humid. Porto’s relative humidity runs between 85 and 92 percent in winter and stays at 65 to 75 percent even in summer, averaging around 80 to 83 percent for the year. Lisbon is slightly drier, with an annual average of 70 to 75 percent. Even the Algarve, Portugal’s driest region, averages 65 to 70 percent.
Spain’s interior and Mediterranean coast tend to be much drier in the air. Madrid and the Andalusian lowlands have notably lower humidity, especially in summer. This is one reason the heat feels different in the two countries: a 35°C afternoon in Lisbon can feel sticky and heavy, while the same temperature in Madrid feels more like standing in an oven with dry, baking air.
Summer Heat: Coastal Cooling vs. Interior Extremes
One of the most striking climate differences is how each country handles summer. Portugal’s western coast benefits from a seasonal wind pattern called the Nortada, a northerly wind driven by the interaction between the Azores High pressure system over the Atlantic and a thermal low that forms over the hot interior of the peninsula. This wind blows along the coast at considerable strength, with average speeds around 15 meters per second and gusts reaching 25 meters per second. It also triggers coastal upwelling, pulling cold water from the deep ocean to the surface, which cools the air near shore and suppresses humidity over land.
The result is that Portuguese beach towns can feel surprisingly cool in July and August, even while temperatures inland climb past 40°C. Mora, a town about 100 kilometers east of Lisbon, recorded 46.6°C in June 2024, a record for mainland Portugal. The coast, just a short drive away, was far more bearable.
Spain has its own version of extreme interior heat. The Meseta Central, the vast plateau that covers much of central Spain, bakes in summer, with average daytime highs of 24 to 27°C in the southern half and 21°C in the north. Those are averages, though. Peak temperatures regularly push well above 40°C in Andalusia and the southern meseta. Seville is one of the hottest cities in Europe during summer, logging 3,279 sunshine hours per year, more than any other major city on the peninsula.
Winter Cold and Snowfall
Winters reveal another gap. Portugal’s winters are mild along the coast, with Lisbon rarely dipping below 8°C. Rain is frequent, especially in the north, but freezing temperatures at sea level are uncommon. The interior highlands are a different story: Serra da Estrela, Portugal’s highest mountain range at just under 2,000 meters, still averages about 28 snow days per year at its mid-altitude weather station (1,380 meters), though that number has dropped sharply from 53 days in the 1950s. At the summit plateau, snow cover lasts roughly 120 days per year, down from about 170 days in the late 19th century.
Spain has far more mountain territory and far colder winters in its interior. The Meseta Central experiences strong winds, high humidity, and frequent frost in winter, despite relatively low precipitation. The northern foothills of the Iberian System are among the coldest non-mountain areas in the country. Spain’s Pyrenees and Sierra Nevada carry snow well into spring, and the Sierra Nevada maintains ski runs at altitudes Portugal simply doesn’t have. The Spanish interior’s continental climate creates a temperature range that Portugal, buffered by the ocean, rarely matches: it is common for Madrid to see frost in January and 38°C heat in July.
Sunshine Hours Across the Peninsula
Both countries are among Europe’s sunniest, but the distribution differs. Southern Spain dominates: Seville gets 3,279 hours of sunshine per year, Cádiz logs 3,024, and Almería hits 2,994. In Portugal, Faro leads with 3,036 hours, closely rivaling Spain’s sunniest cities. Lisbon gets 2,806 hours, slightly more than Madrid’s 2,769.
The gap widens in the north. Porto receives 2,468 sunshine hours, which sounds generous until you compare it with Valencia’s 2,956 or Barcelona’s 2,591. Northwestern Spain is the outlier on the Spanish side: A Coruña, in Galicia, gets only 2,010 hours, making it cloudier than any major Portuguese city. Galicia’s climate, in fact, resembles northern Portugal’s far more than it resembles the rest of Spain.
The Galicia-Northern Portugal Connection
The border between the two countries cuts through what is climatically one continuous region in the northwest. Galicia and northern Portugal share heavy Atlantic rainfall, lush green landscapes, moderate temperatures, and high humidity. Viana do Castelo, just south of the Portuguese border, gets 1,466 mm of rain per year. Cross into Galicia and you find similar numbers. This shared wet, mild climate zone is completely unlike the semi-arid conditions found in southeastern Spain or even parts of southern Portugal.
What the Differences Mean in Practice
If you’re comparing the two countries for travel, relocation, or just curiosity, the key patterns are straightforward. Portugal is generally wetter, more humid, and more moderated by the ocean. You won’t find the same temperature extremes there that you will in Spain’s interior. Spain offers greater climate diversity overall, from the wet green northwest to the near-desert southeast, from mild Mediterranean coasts to a central plateau with genuinely cold winters and scorching summers.
Portugal’s Algarve and Spain’s Costa del Sol are the closest climate twins between the two countries: both are warm, sunny, and relatively dry. Move north or inland in either country and the climates begin to diverge, with Spain trending toward continental extremes and Portugal staying closer to its Atlantic baseline.