Lisbon weather in September
Lisbon averages 26°C by day and 18°C at night in September, with the sea at 19°C and 4 days with at least 1 mm of rain. It cools by about 3°C into October.
Day
26°C
Night
18°C
Sea
19°C
Rainy days
4
Flight from London
2½h
What September feels like
September is hot in Lisbon: proper beach weather.
The sea is 19°C: refreshing, and chilly for most people after a few minutes.
Rain is occasional, on about 4 days.
Of the 48 sun destinations we track, Lisbon is the #41 warmest in September, and #20 of 23 within 5½ hours of the UK.
Want it warmer in September?
These are hotter than Lisbon this month for at most an hour and a half more flying:
Lisbon weather by month
September is highlighted. Compare with August and October, or see the full year in Lisbon.
Lisbon in September: quick answers
Is Lisbon hot in September?
September is hot in Lisbon: proper beach weather. Average highs are 26°C and lows 18°C.
Can you swim in Lisbon in September?
The sea is 19°C: refreshing, and chilly for most people after a few minutes.
Does it rain in Lisbon in September?
Rain is occasional, on about 4 days.
What is the warmest month in Lisbon?
August, at an average high of 29°C. The coolest is January at 15°C.
How long is the flight to Lisbon from the UK?
About 2½h direct from London, estimated from the 1,571 km distance. Check your airline for exact times.
Still choosing? See where is hot in September for every destination ranked by temperature, sea and flight time.
How we measured this
Averages of every day in September from 2016 to 2025, from the Open-Meteo historical weather archive (ECMWF ERA5 reanalysis). Sea temperature is the 2023 to 2025 average from the Open-Meteo marine archive. A rainy day has at least 1 mm of rain. Reanalysis describes an area about 25 km across, so sheltered resorts can run a degree or two warmer. Flight time is a distance-based estimate from London Heathrow.
Planning Lisbon in September?
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