Sits around the middle of the year.
May in context
How it compares to the rest of the year in Lisbon.
Typical rainfall for the year.
Long daylight hours.
Close to the yearly wind average.
UV runs high compared with most months.
Humidity stays close to the yearly norm.
Monthly climate breakdown
A detailed look at the typical climate conditions for May.
Thermal profile
Temperature
Typical daytime high
- Nighttime low
-
- Feels like (avg)
-
Light window
Sunshine
14.3 h
Average daylight
- UV index (max)
- 8
- Typical sun hours
- 05:24 - 19:41
Wet-day pattern
Rain & Snow
Typical rainfall
- Rainy days
- 8 days
- Cloud cover (avg)
- 45%
Air feel
Humidity & Wind
73%
Average humidity
- Wind (avg)
-
- Wind (max gusts)
-
Historical daily baseline
Daily climate explorer
Pick a day to inspect the usual conditions through May in Lisbon. Based on a 30-year historical climate baseline, not a forecast.
Primary control
Select a day
Scroll to compare daily conditions. The summary updates with your selection.
Secondary context
Monthly trend
Median daytime highs across the month, with a softer low line.
Day 15 selected for May. Temperature 19.9°C.
Historical disruption baseline
Typical disruptions in May
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in May.
Washout risk Measures: Washout day risk. Observed about 9% of days (2.7 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.7 days / month
- Share of days
- ~9% of days
- Upper edge
- Up to ~22mm (P95)
Why this matters
Washout conditions are possible on ~3 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Strong gusts Measures: Strong gust days (>=60 km/h). Observed about 4% of days (1.2 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.2 days / month
- Share of days
- ~4% of days
- Upper edge
- Up to ~73km/h (P95)
Why this matters
Strong gusts are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Stormy conditions Measures: Storm-impact proxy days. Observed about 3% of days (0.8 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.8 days / month
- Share of days
- ~3% of days
- Upper edge
- Up to ~70km/h (P95)
Why this matters
Stormy conditions are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Rain disruption Measures: Likely rain disruption days. Observed about 9% of days (2.7 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.7 days / month
- Share of days
- ~9% of days
- Upper edge
- Up to ~22mm (P95)
Why this matters
Rain disruption risk appears on ~3 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Hot feels-like days Measures: Hot feels-like days (>=32C). Observed about 3% of days (0.9 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.9 days / month
- Share of days
- ~3% of days
- Upper edge
- Up to ~35°C (P95)
Why this matters
Feels-like heat >=32C is possible on ~1 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Hot days Measures: Hot days (>=30C). Observed about 2% of days (0.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.6 days / month
- Share of days
- ~2% of days
- Upper edge
- Up to ~33°C (P95)
Why this matters
Hot days are possible on ~1 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Show all disruptions (14 more)
Washout run Measures: Multi-day washout runs. Observed about 0.6 days/month in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.6 days / month
- Share of days
- —
- Upper edge
- Up to ~18mm (P95)
Why this matters
Multi-day washout runs are possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 4% of days (1.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.4 days / month
- Share of days
- ~4% of days
- Upper edge
- Up to ~27mm (P95)
Why this matters
Heavy rain is possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Gusty days Measures: Gusty days (>=40 km/h). Observed about 50% of days (15.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
15.6 days / month
- Share of days
- ~50% of days
- Upper edge
- Up to ~62km/h (P95)
Why this matters
Gusty conditions are possible on ~16 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 34% of days (10.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
10.5 days / month
- Share of days
- ~34% of days
- Upper edge
- Up to ~98% (P95)
Why this matters
Cloudy skies are possible on ~11 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wet days Measures: Wet days (>=0.1mm). Observed about 34% of days (10.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
10.5 days / month
- Share of days
- ~34% of days
- Upper edge
- Up to ~16mm (P95)
Why this matters
Measurable rain is possible on ~10 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 25% of days (7.9 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
7.9 days / month
- Share of days
- ~25% of days
- Upper edge
- Up to ~21h (P95)
Why this matters
Several rainy hours are possible on ~8 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
High humidity Measures: High humidity days (RH >=80%). Observed about 24% of days (7.5 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
7.5 days / month
- Share of days
- ~24% of days
- Upper edge
- Up to ~91% (P95)
Why this matters
High humidity is possible on ~8 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 16% of days (5.0 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
5.0 days / month
- Share of days
- ~16% of days
- Upper edge
- Up to ~22h (P95)
Why this matters
Wet-most-of-day conditions are possible on ~5 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 14% of days (4.2 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
4.2 days / month
- Share of days
- ~14% of days
- Upper edge
- Up to ~99% (P95)
Why this matters
Mostly cloudy skies are possible on ~4 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Breezy days Measures: Breezy days (mean wind >=25 km/h). Observed about 12% of days (3.6 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
3.6 days / month
- Share of days
- ~12% of days
- Upper edge
- Up to ~34km/h (P95)
Why this matters
Breezy conditions are possible on ~4 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 4% of days (1.2 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.2 days / month
- Share of days
- ~4% of days
- Upper edge
- Up to ~100% (P95)
Why this matters
Overcast skies are possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Fog-likely signal Measures: Fog-likely visibility proxy. Observed about 1% of days (0.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.4 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~93% (P95)
Why this matters
Fog-likely conditions are possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data Measures: Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data. Observed about 1% of days (0.4 days/month) in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.4 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~93 (P95)
Why this matters
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data is possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Feels-like heatwave Measures: Feels-like heatwave runs (>=3 days). Observed about 0.1 days/month in May. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.1 days / month
- Share of days
- —
- Upper edge
- Up to ~33°C (P95)
Why this matters
Feels-like heatwave runs are possible on ~0 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Travel planning FAQ
Frequently asked questions
Quick answers to the weather questions you ask the most.
Is May a good time to visit Lisbon?
Typical May days in Lisbon reach highs of 21°C (70°F) with nights around 14°C (57°F). It usually feels mild by day and cool after dark. Overall, May sits in the middle of the Lisbon climate range.
What are temperatures like in May?
In May, you can usually expect highs of 21°C (70°F) and lows near 14°C (57°F). That means mild days and cool nights, so pack layers you can add or remove.
How much does it rain in May?
Rainfall in May averages 40 mm (1.6 in) across roughly 8 days. Overall it is a moderately wet time of year, so showers are usually brief rather than all-day downpours.
How many hours of daylight are there in May?
You can expect about 14 hours of daylight in May. Sunrise is typically around 05:24 and sunset near 19:41. You get long days with comfortable amounts of daylight.
How strong is the sun in May?
UV levels frequently reach very high levels (around 8), so strong sun protection is essential, especially around midday.
Is it windy in May?
In May, average wind speeds are around 17 km/h (11 mph), with gusts on the windiest days reaching about 54 km/h (34 mph). On the ground, it is it can feel quite windy at times, particularly when weather systems move through.