Lisbon sits at 38.7N latitude on the Atlantic coast at just 2m elevation. The city has a Mediterranean climate strongly moderated by the Atlantic Ocean. Summers are warm and dry with cooling sea breezes. Winters are mild and wet. Lisbon is one of Europe’s sunniest capitals with 2,825 hours of sunshine annually. This guide provides exact monthly data for planning your trip.
Lisbon Monthly Weather Data
The table shows average daily high temperatures, total monthly rainfall, relative humidity, monthly sunshine hours, and average Atlantic sea temperatures for Lisbon.
| Month | High (°C) | High (°F) | Rain (mm) | Humidity | Sun Hours | Sea Temp |
|---|---|---|---|---|---|---|
| January | 15°C | 59°F | 100mm | 77% | 145 | 15°C |
| February | 16°C | 61°F | 85mm | 74% | 150 | 15°C |
| March | 18°C | 64°F | 53mm | 70% | 210 | 15°C |
| April | 19°C | 66°F | 62mm | 67% | 240 | 16°C |
| May | 22°C | 72°F | 39mm | 65% | 285 | 17°C |
| June | 25°C | 77°F | 15mm | 62% | 315 | 18°C |
| July | 28°C | 82°F | 4mm | 58% | 355 | 19°C |
| August | 28°C | 82°F | 6mm | 59% | 345 | 20°C |
| September | 26°C | 79°F | 33mm | 65% | 270 | 19°C |
| October | 22°C | 72°F | 80mm | 71% | 215 | 18°C |
| November | 18°C | 64°F | 114mm | 76% | 155 | 17°C |
| December | 15°C | 59°F | 118mm | 78% | 140 | 16°C |
Lisbon Weather Patterns Throughout the Year
Lisbon receives 709mm of rain annually with a strong Mediterranean pattern: very dry summers, wet winters. The city gets 2,825 hours of sunshine per year. The highest recorded temperature was 44.0°C (111°F) in August. The coldest was 1.2°C (34°F) in February. The Atlantic Ocean keeps temperatures moderate; extreme heatwaves are uncommon and usually broken by sea breezes within 2-3 days.
Winter in Lisbon: December Through February
December through February are mild by European standards. Highs average 15-16°C (59-61°F) with lows of 8-10°C (46-50°F). This is the rainy season: December gets 118mm, January 100mm, February 85mm. Rain typically comes in short, heavy bursts rather than all-day drizzle. Sunshine averages 145-155 hours per month. The sea temperature holds at 15°C. Pack a waterproof jacket and layers. Hotel rates are at their lowest (except Christmas/New Year). Tourist crowds are minimal.
Spring in Lisbon: March Through May
Spring warms gradually. March averages 18°C (64°F) with 53mm of rain. By May, highs reach 22°C (72°F) with 39mm of rain. Sunshine jumps from 210 hours in March to 285 hours in May. Sea temperature slowly climbs from 15°C to 17°C. April and May are excellent months for sightseeing with comfortable walking temperatures and manageable crowds. Jacaranda trees bloom purple across the city in May.
Summer in Lisbon: June Through August
Summer is warm, dry, and sunny. July and August both average 28°C (82°F) but the Atlantic breeze (the nortada) keeps it comfortable. Rainfall is near zero: 4mm in July, 6mm in August. Humidity drops to 58-59%, the lowest of the year. Sunshine peaks at 345-355 hours per month. The sea warms to 19-20°C, swimmable but cooler than the Mediterranean. August is peak tourist season with the highest hotel rates and crowded attractions. The afternoon wind can be strong enough to make beach umbrellas unusable at Cascais and Estoril.
Autumn in Lisbon: September Through November
September extends summer with highs of 26°C (79°F), sea at 19°C, and just 33mm of rain. October cools to 22°C (72°F) with 80mm of rain. November drops to 18°C (64°F) with 114mm of rain. September and early October are ideal: summer weather without August crowds, warm sea, and hotel rates dropping after the first week of September. November marks the start of the rainy season. The best time to visit Lisbon guide covers seasonal strategy in detail.
