Lisbon has a Subtropical-Mediterranean climate, characterized by warm to hot, dry summers and mild to cool, wet winters. Influenced with the Gulf Stream, the city enjoys the mildest weathers in Europe. The average annual temperature is 17 °C (63 °F). Basically, there are two noticeable weather condition namely the warmest average max/ high temperature which typically ranges from 26 to 32 °C (79 to 90 °F) during the day and around 18 °C (64 °F) at night in the month of August and the coolest average min/ low temperature ranges from 8 to 17 °C (46 to 63 °F) during the day and 4 to 12 °C (39 to 54 °F) at night in January.
Generally, May to October is the typical summer seasons with an average temperature of 25 °C (77 °F) during the day and 16.2 °C (61.2 °F) at night. On the other hand, the coldest months are December, January and February with an average temperature of these three months amounting 15.2 °C (59.4 °F) during the day, 8.9 °C (48.0 °F) at night.
Lisbon is a perfect travel destination all year round because it is blessed with mild weather and has no extreme weather conditions. Summer season is typically hot during the day and cold at night, best for strolling and swimming in the beach. It is also the best time to enjoy Plenty of Lisbon’s biggest and most popular festivals like Cascais International Sailing Week and also the BaixAnima Street Festival. During winter months, rain mainly occurs. The best time for a visit may be the transition months of November, March and April where the temperature exceeds20 °C (68 °F), with an average temperature of these three months amounting 18.5 °C (65 °F) during the day and 11.2 °C (52.2 °F) at night.