Porto weather by month

When to go to Porto

For beach weather, look at months where the daytime average clears 25°C and rainy days stay low: July, August. December is the wettest month (170 mm, about 13 rainy days) and July the driest (22 mm). The sea is warmest in September at 17.5°C and coolest in February at 13.0°C.

Getting there

A direct flight from London Gatwick to Francisco de Sá Carneiro Airport (OPO, 13 km from Porto) takes roughly 2 h 24 min - short-haul (up to 4.5 h) by UK standards. Time-zone: Europe/Lisbon.

Records and extremes, 1991-2020

The hottest day recorded in Porto between 1991 and 2020 reached 38.4°C on 7 July 2013; the coldest fell to -1.1°C on 9 January 2009. In August one day in ten tops 31.5°C and about 16% of days pass 30°C; in January one night in ten drops to 2.5°C or below. The wettest single month of the period was March 2001 with 545 mm, against a March average of 123 mm.

Spring: comfortable days, but keep a rain plan

March brings daytime averages of 16°C, rising to 18°C in April and 20°C in May. That makes spring a good fit for exploring on foot without summer warmth, though it is not a reliably dry season. April averages 12 rainy days and May still has 11, so pack a waterproof rather than treating showers as an unlikely interruption. Evenings need another layer: March nights average 8°C, with May reaching 12°C. May offers more scope for time outdoors, with 7 hours of sunshine, but the sea remains cool at 15°C. Choose spring for mild city weather, not for a swimming-focused holiday.

Summer and September: the strongest weather window

June marks a useful shift towards drier weather, with 23°C days and 6 rainy days on average. July and August are the clearest choices if keeping rain disruption low matters most: each averages 4 rainy days, with daytime temperatures of 25°C and 26°C respectively. Light clothing makes sense during the day, with sun protection and a layer for evenings. September remains a strong option, averaging 24°C by day and 16°C at night, although rain becomes a little more frequent. Swimming is the compromise throughout this period. The sea averages 17°C from June through August, then reaches 18°C in September, so warm air does not mean warm water.

Late autumn and winter: mild afternoons, wetter plans

October still averages 20°C by day, but its 13 rainy days make it less dependable for outdoor plans than September. November cools to 16°C and keeps the same frequency of rain. Winter suits travellers who are happy to work around wet weather rather than spend every day outdoors. December averages 14°C by day, January 13°C and February 14°C, so afternoons can be manageable with layers. Nights are colder, reaching an average of 6°C in January and February. Pack a warm layer, waterproof jacket and shoes that cope with rain. February offers 5 hours of sunshine compared with December's 3, but it is still cool-weather city travel.