Lisbon has a mild Mediterranean-Atlantic climate: hot, bone-dry summers and cool, wet winters, with two shoulder seasons that are the sweet spot most people miss because they default to July. The numbers below come from the long-run climate record (the chart on this page plots all twelve months). The short version: the weather is kindest in late spring and early autumn, the crowds and prices are worst in high summer, and winter is a genuine bargain if you can live with rain and shorter days.
Two things skew the calendar in ways weather alone won’t tell you. First, this is a hill city of open-air viewpoints, terraces and grilled-fish lunches — pleasures that lose their point in drizzle, so a wet week costs you more than the rain gauge suggests. Second, a handful of big events swing hotel prices hard, and one of them lands in a month that’s otherwise the best value of the year.
A few practicalities that shift by season. Daylight swings a lot for a southern city: you get roughly nine and a half hours of light around the December solstice against nearly fifteen in June, which matters when your days are built around viewpoints and sunsets. The Atlantic keeps summer nights bearable — evenings cool into the high teens even in August — so a light layer earns its place year-round. And the rain, when it comes, tends to arrive in heavy Atlantic bands rather than all-day drizzle, so a wet forecast often still leaves dry windows to work with if you stay flexible.
Lisbon month by month
- January: the coldest month, highs around 15°C, and among the wettest, with roughly 8 rainy days. Cheap and quiet, but daylight is short and terrace weather is a gamble. City museums and the castle carry the trip.
- February: similar temperatures, slightly drier on average (about 6 wet days). Carnival falls here some years. Still low season, still a bargain, still bring a waterproof.
- March: warming to about 17°C but statistically one of the wettest months (around 9 rainy days). Unpredictable — you might get a run of glorious clear days or a soaking. Prices haven’t climbed yet.
- April: highs near 19°C, still around 9 rainy days, and Easter can spike prices for a week. Spring blossom in the gardens; a decent bet if you dodge the Easter surge.
- May: the rain drops off sharply (about 4 wet days) and highs reach a comfortable 23°C. Arguably the best all-round month — warm enough for everything, not yet crowded or expensive.
- June: warm and dry (25°C, ~4 wet days) with long evenings. The Santo António festival around 12–13 June turns Alfama into a street party of grilled sardines and paper decorations — fun, but book accommodation early and expect crowds.
- July: hot and effectively rainless (28°C, ~1 wet day). Peak crowds, peak prices, and the beaches at Cascais and Caparica are heaving at weekends. Great weather, worst value.
- August: the hottest month (highs around 28°C, often spiking past 35°C in heatwaves) and the driest. Many local businesses close as Lisboetas leave for holidays, so parts of the city feel emptied of actual residents while the tourist core is at its most packed.
- September: the other sweet-spot month — still 26°C and dry (~4 wet days), the sea is at its warmest after a summer of heating, and the July–August crush eases as the month goes on and families return home for school. Prices soften from mid-September, and the light turns golden for the evening viewpoints. If you can only travel in the warm season, this is the month to pick over July.
- October: mild (23°C) but the rain returns hard — around 10 wet days, the wettest stretch of the year begins. Pleasant between showers, and much cheaper than summer.
- November: cooler (18°C) and wet (~10 rainy days), and normally excellent value — except the Web Summit tech conference, usually held this month, books out the city and doubles hotel rates for its week. Check the dates before you commit.
- December: mild for a European December (16°C) but wet (~7 rainy days), with Christmas lights and a low-season feel until New Year’s Eve, which fills the riverfront.
Weather, crowds and price by season
| Period | Weather | Crowds | Prices | Verdict |
|---|---|---|---|---|
| Dec–Feb | Mild, wet, short days | Low | Lowest | Bargain if you accept rain |
| Mar–Apr | Warming, still wet | Rising | Low–mid | Gamble on weather; watch Easter |
| May | Warm, mostly dry | Moderate | Mid | Best all-rounder |
| Jun | Warm, dry, festive | High | Mid–high | Great, but book early |
| Jul–Aug | Hot, dry | Peak | Highest | Best weather, worst value |
| Sep | Warm, dry, warm sea | High, easing | Mid–high | Best value in the good weather |
| Oct–Nov | Mild, turning wet | Low | Low (bar Web Summit) | Cheap, hit-and-miss skies |
The verdict
Best overall: late May. You get near-summer warmth and dry days without July’s crowds or prices, and the viewpoints, ferries and beaches all deliver. September is the close runner-up and edges it if you want warm sea for a beach day trip. Best value: November — genuinely cheap and still mild, as long as you check that your dates miss the Web Summit week, which is the one time the bargain evaporates. Avoid, if you have a choice: August — you’re paying the highest prices to share the packed core with everyone else while half the neighbourhood tascas are shut for the owners’ holidays, and the midday heat on the treeless hills is punishing. If August is your only option, start early, rest through the hottest hours, and plan a beach or ferry day to catch the breeze off the water.
Whatever month you land in, the weather steers the plan more than the calendar does. On a wet day, front-load the museums and save the miradouros for the clear spell — the things-to-do guide flags which sights hold up in rain. If you’re coming in the warm, dry months, a beach or Sintra day is the obvious add — see the day-trips guide — and if you’re chasing the lowest room rates, cross-reference the cheap months against the where-to-stay guide before you book.