Best Time to Visit Sintra
Recommended: Mar to May
When to go
March-May and September-October have mild weather and thinner crowds than summer. June-August is the worst combination of heat, humidity, and coach-tour volume; weekday mornings help but don't solve it. Sintra runs several degrees cooler and foggier than Lisbon year-round, so bring a layer even in July.
Month by month in Portugal
Sintra sits in Portugal, so the country's broader seasonal pattern applies. June to September is warm and dry nationwide, especially the Algarve. Lisbon and Porto are most pleasant April to June and September to October. November to February brings real rain to Porto and the north; the Algarve stays milder and drier.
Jan-FebMild by Canadian standards but genuinely wet in Porto and the north. Algarve and Lisbon stay drier, around 14-16C, lowest prices of the year.
Mar-AprRain tapers through April, almond blossoms inland, good hiking weather, still too cool for most people to swim in the Algarve.
MayWarming fast, still green, before summer crowds and heat arrive. Strong shoulder-season pick for Lisbon and Porto.
JunAlgarve summer starts in earnest and the sea is warm enough to swim. Lisbon and Porto heat up but stay tolerable.
Jul-AugPeak heat and peak crowds everywhere. Inland Alentejo regularly tops 35C; Algarve beaches are packed and priciest of the year.
SepThe best month for most of the country. Summer heat breaks, the sea is still warm, crowds thin after the third week.
OctReliable sun in the Algarve and Lisbon, first rain returns to Porto and the north, harvest season in the Douro valley.
Nov-DecRainy season sets in properly in Porto and the north. Algarve stays the mildest, driest region; Christmas markets and low prices in the cities.