May to June and September to October. Month by month below, with the weather, what's on and what it costs to fly there from your city.
Late spring and early autumn give warm weather, sunshine and fewer crowds; July and August are the busiest and hottest.
5 of the 8 travel guides we read name these months.
Average high and low in Algarve, and days with rain
JanuaryChecking fares…Coolest month: mild days, cool evenings, rain over about six days; good for golf and walking.Faro averages: high 16C, low 8C, sea 17C.
FebruaryChecking fares…Still mild, less rain than December or January, and a very quiet coast.The February carnival in Loulé is called the best in the region.
MarchChecking fares…Days get longer and sunnier, more than 240 hours of sunshine; coastal walks are good but the sea is still cool.March is the best time for Portugal's good weather, before tourist crowds, per one specialist (Portugal-wide).
AprilChecking fares…Pleasant and green, highs around 21C; the sea is still too cool for most swimmers.April to June is good for outdoor activities such as the Seven Hanging Valleys Trail.
Best timeMayChecking fares…One of the best months overall: warm days, over 300 hours of sunshine, little rain, before summer crowds.Faro averages: high 24C, sea 19C, rain 26 mm over about 4 days.Rain is rare between May and September.
Best timeJuneChecking fares…Summer starts with highs near 27C and almost no rain; beaches busy but not yet at their peak.The high season runs June to September, coinciding with summer vacations.
JulyChecking fares…Sunniest month, about 360 hours of sun and highs near 29C; beaches and resorts at their busiest.July and August can be very hot.
AugustChecking fares…As hot as July with the warmest sea of the summer, about 22C.August can get uncomfortably crowded, with popular spots such as Benagil Cave jam-packed.
Best timeSeptemberChecking fares…Still summer weather and a warm sea but fewer crowds after the first weeks; one of the best beach months.Many locals call it the best time to visit; crowds fade and the ocean is calm.Rain is only about 22 mm over about 2 days.
Best timeOctoberChecking fares…Warm and usually sunny, highs around 23C, sea above 21C; first autumn rains arrive over about six days.September and October are shoulder season: pleasant temperatures and only occasional showers.
NovemberChecking fares…Milder and wetter, highs near 20C; good for golf and hiking.Low-season hotel rates run from November 1 to March 31 in Portugal.
DecemberChecking fares…Faro averages: high 17C, low 10C, the most rain of the year (90 mm over 7 days) and only 5.1 hours of sun a day.Winter days hover around 15C-20C; bring a warm jacket for wind and rain.Weather: Algarve averages (long-term averages), as listed in its climate table on Wikipedia.
Live fares from your airport. Watch them and we alert you when they drop.
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Capitol Reef National Park