Porto and its metropolitan area feature a Mediterranean climate (Köppen: Csb) with mild wet winters and warm dry summers. According to the Troll-Paffen climate classification, Porto has a warm-temperate subtropical climate (Warmgemäßigt-subtropisches Zonenklima),Climatic map by Istituto Geografico De Agostini, according to Troll-Paffen climate classification and a subtropical climate according to Siegmund/Frankenberg.Die Klimatypen der Erde - Pädagogische Hochschule in Heidelberg Porto is the wettest major city with a Mediterranean climate.
Classifications
Temperature Normals
Porto has generally moderate temperatures. The average annual high is around and average low around . The climate is also only mildly seasonal, from a maxima of in January to in August, while minima is around in January and in July and August. In its metropolitan area, January lows can vary between at the coast and on the mountainous interior, and August highs vary between at the coast and in the interior near the Douro valley.
Extremes Due to its coastal position, temperatures below freezing () are rare, and frosts are never severe. Porto is placed in the USDA hardiness zone 10a. The lowest temperature ever recorded in the city was on 11 January 1941.Extremes Instituto Português do Mar e da Atmosfera, IPMA
Precipitation Porto has abundant levels of precipitation. Despite averaging above of precipitation a year, July and August are relatively dry with around falling each month. The wettest period is between October and February, mostly between October and December, the wettest month.
Humidity The average relative humidity is around 77%. 81% from November to January and 73% in the summer. Summer can be slightly muggy in the hottest days but is generally comfortable, as temperatures rarely surpass .
Other phenomena
Sunshine, UV and daylight Despite its precipitation, the total hours of sunshine are relatively normal for a region of its latitude. Winters, especially December, are somewhat dull, and summers are sunny.
Wind As a coastal Atlantic city, winds are most predominant in winter. In the summer, nortada winds prevail and can refresh the city in the hottest days. The city centre is sheltered and seldom gets any strong winds.
+Average wind speed (km/h) 1971-2000JanFebMarAprMayJunJulAugSepOctNovDecYearPorto (Fontainhas)19.619.7 19.219.018.116.917.316.315.216.818.420.018.0Porto São Gens8.68.7 8.89.08.37.77.46.86.56.56.56.98.4Porto Pedras Rubras15.716.3 15.015.014.913.512.512.211.913.314.216.314.2
Sea Temperature +Average sea temperature, according to seatemperature.org:JanFebMarAprMayJunJulAugSepOctNovDecYear +Average sea temperature, according to surf-forecast.com:JanFebMarAprMayJunJulAugSepOctNovDecYear
1961-1990 data
References
External links