San Sebastian, which has a maritime climate, is one of the rainiest cities in Spain. The rains are abundant in all seasons, especially in autumn, being non-existent water supply problems. Precipitation as snow is low (between 1 and 3 days a year, although there are winters like 2004-05 and 2009-10 in which the number of days was higher than 10) in turn, the number of frost usually varies between 5 and 10 per year. The gales are relatively common. In early October are given what the locals call "Riptide" great tidal waves.

Temperatures are mild and temperate (average 15 ° C), although in the months of June to September dehumedad lot (located at around 65% -70% most of the day of the year) causes sensations greater thermal heat.The wind blows from the south wind (which causes foehn effect) raises the temperature to 20 ° C in winter and up to 37-38 ° C in summer, the humidity down considerably (although this situation of high summer temperatures often last a few days or even hours interrupted with a twist of wind component NO, which comes from the Cantabrian Sea, this phenomenon is the 'gale' and is accompanied by a sharp drop in temperatures and times of clouds, storms or even sea fog).

In situations of cold air invasion from Europe, San Sebastian is one of the first cities to feel the cold and often the most affected coastal Spanish capital because of its proximity to France, this is because the winds are not maritime route so unless you are tuned in other cities, so it is not unusual to see the Concha beach covered with snow. The extremes of San Sebastian are 40 ° C and -13 ° C, both taken at the airport.