Lisbon has a Mediterranean climate with mild, rainy winters and warm to hot, dry summers. The average annual temperature is 17.4 °C (63.3 °F), 21.3 °C (70.3 °F) during the day and 13.5 °C (56.3 °F) at night.
In the coldest month – January – the highest temperature during the day typically ranges from 11 to 19 °C (52 to 66 °F), the lowest temperature at night ranges from 3 to 13 °C (37 to 55 °F) and the average sea temperature is 16 °C (61 °F). In the warmest month – August – the highest temperature during the day typically ranges from 25 to 32 °C (77 to 90 °F), the lowest temperature at night ranges from 14 to 20 °C (57 to 68 °F) and the average sea temperature is around 20 °C (68 °F).
Among European capitals, Lisbon ranks among those with the warmest winters and has the mildest winter nights out of any major European city, with an average of 8.3 °C (46.9 °F) in the coldest month, and 18.6 °C (65.5 °F) in the warmest month. The coldest temperature ever recorded in Lisbon was −1.2 °C (30 °F) in February 1956. The highest temperature ever recorded in Lisbon was 44.0 °C (111.2 °F) on 4 August 2018.
The city has around 2,806 hours of sunshine per year, averaging 4.6 hours of sunshine per day in December and 11.4 hours of sunshine per day in July, though when disregarding the duration of the day August is actually the sunniest, with over 80% chance of direct sunlight hitting the ground.
Lisbon has around 750 mm (30 in) of precipitation per year. November and December are the wettest months, accounting for a third of the total annual precipitation. July and August are the driest.