December in Porto averages a daily high of 14.4°C with nights around 7.3°C. Expect roughly 14.9 wet days totalling 177.5mm. Demanding conditions — pack for it and plan indoor options.
Across the year, the best time to visit Porto is June–September.
Based on PORTO, PO (1.9km), 1995–2024. 17 years of December data.