section_path: Geography/Climate
section_name: Climate
paragraph_text: Climate
  
  Portugal is mainly characterised by a Mediterranean climate, temperate maritime climate in high altitude zones of the Azorean islands; a semi-arid climate in parts of the Beja District far south and in Porto Santo Island, a hot desert climate in the Selvagens Islands and a humid subtropical climate in the western Azores, according to the Köppen-Geiger climate classification. It is one of the warmest countries in Europe: the average temperature in mainland Portugal varies from 10–12 °C (50.0–53.6 °F) in the mountainous interior north to 17–19 °C (62.6–66.2 °F) in the south and on the Guadiana river basin. There are variations from the highlands to the lowlands. The Algarve, separated from the Alentejo region by mountains reaching up to 900 metres (3,000 ft) in Alto da Fóia, has a climate similar to that of the southern coastal areas of Spain or Southwest Australia.
  
  Annual average rainfall in the mainland varies from just over 3,200 millimetres (126.0 in) on the Peneda-Gerês National Park to less than 500 millimetres (19.7 in) in southern parts of Alentejo. Mount Pico receives the largest annual rainfall (over 6,250 millimetres (246.1 in) per year), according to Instituto Português do Mar e da Atmosfera. In some areas, such as the Guadiana basin, annual diurnal average temperatures can be as high as 24.5 °C (76.1 °F), and summer's highest temperatures are routinely over 40 °C (104 °F). The record high of 47.4 °C (117.3 °F) was recorded in Amareleja.
  
  Snowfalls occur regularly during winter in the interior North and Centre, particularly in the highlands. In these regions, temperatures can drop below −10.0 °C (14.0 °F), and snow may fall any time from October to May. In the South, snowfalls are rare but can still occur at the highest elevations. While the official absolute minimum by IPMA is −16.0 °C (3.2 °F) in Penhas da Saúde and Miranda do Douro, lower temperatures have been recorded. Continental Portugal receives around 2,300-3,200 hours of sunshine annually, an average of 4–6 hours in winter and 10–12 hours in the summer, with higher values in the south-east, south-west, Algarve coast and lower in the north-west.
  
  Portugal's central west and southwest coasts have an extreme ocean seasonal lag; sea temperatures are warmer in October than in July and are their coldest in March. The average sea surface temperature on the west coast of mainland Portugal varies from 14–16 °C (57.2–60.8 °F) in January−March to 19–21 °C (66.2–69.8 °F) in August−October while on the south coast it ranges from 16 °C (60.8 °F) in January−March and rises in the summer to about 22–23 °C (71.6–73.4 °F), occasionally reaching 26 °C (78.8 °F). In the Azores, around 16 °C (60.8 °F) in February−April to 22–24 °C (71.6–75.2 °F) in July−September, and in Madeira, around 18 °C (64.4 °F) in February−April to 23–24 °C (73.4–75.2 °F) in August−October.
  
  Azores and Madeira have a subtropical climate, although variations between islands exist. The Madeira and Azorean archipelagos have a narrower temperature range, with annual average temperatures exceeding 20 °C (68 °F) in some parts of the coast. Some islands in Azores have drier months in the summer. Consequently, the islands of the Azores have been identified as having a Mediterranean climate, while some islands (such as Flores or Corvo) are classified as Humid subtropical, transitioning into an Oceanic climate at higher altitudes. Porto Santo Island in Madeira has a warm semi-arid climate. The Savage Islands, which are part of the regional territory of Madeira and a nature reserve are unique in being classified as a desert climate with an annual average rainfall of approximately 150 millimetres (5.9 in).
  
  Climate change in Portugal is causing rising temperatures and longer-lasting heat waves, decreases in average rainfall and increases in the number of extremely rainy days (causing droughts and floods), and rising sea levels which will threaten the country's many coastal populations. Wildfires are quite common and a major issue in Portugal, being the country with the highest percentage of burned area, on average, in the entire European Union.