Early September 1 September
80°F
Typical afternoon high
4% historical wet-day frequency
Portugal · City
Lisbon
in September.
Is September a good time?
Warm days.
A steady visitor season.
September averages 78°F afternoons and 66°F seas, with about 2 rain days.
- Afternoons
- 78°F
- Sea
- 66°F
- Visitor demand
- 93%of August peak
Historical Grande Lisboa regional averages, not a forecast or a measure of queues. Overnight demand compares average stays per day. Covers Lisbon, Sintra and Cascais; conditions vary within the region.
Overall match
8.1/10 · scores & prioritiesWhat matters most?
Weather 50% · Crowds 30% · Cost 20%
#5 of 12 months here · Balanced mix
Weather10.0/10Excellent
CrowdsSteady all yearsimilar all year; overnight stays do not measure queues
CostPriceyfor Europe
Overall combines weather, overnight demand and cost. It does not include sea temperature.
Plan your September
What to expect.
What should I pack?
Afternoons around 78°F (25°C): T-shirt weather; nights around 60°F (16°C): light layers. About 12 hours of daylight. About 2 rain days in a typical September.
Can I swim in September?
The sea averages 66°F. Our swimming guide: fresh: fine once you are in. Your comfort will vary. This is open water near the coast, not a beach-specific reading.
Monthly coastal averages from NOAA, 2011–2025. Sea temperature is separate from the weather and Overall scores.
A typical day: temperatures & daylightAfternoons, nights, sea temperature & daylight Show detailsHide details
About 12 hours of daylight.
The sun rises about 07:17 and sets about 19:47 (local time, mid-month). Mornings start around 60°F (16°C); afternoons reach about 78°F (25°C). Expect rain on about 2 days in a typical September.
Typical afternoon
78°F (25°C)
average daily high, 15 recent Septembers
Night low
60°F (16°C)
average daily minimum
Sea
66°F (19°C)
fresh; open water near the coast, NOAA satellite record 2011–2025
Daylight
12h 30m
on the 15th, computed from latitude
Early, middle or late?
Early or late September?
Early and late September have similar afternoon averages. The afternoon high averages 80°F on the 1st, versus 76°F on the 30th. Historical wet-day frequency rises from 4% to 11% between those dates.
Mid September 15 September
78°F
Typical afternoon high
12% historical wet-day frequency
Late September 30 September
76°F
Typical afternoon high
11% historical wet-day frequency
Historical daily averages from 2011–2025, smoothed over two weeks. A seasonal pattern, not a forecast. This does not establish which week has the lowest prices or fewest visitors.
Daily calendar & holiday datesSeptember 2027 · historical weather & dated holidays Show calendarHide calendar
September 2027 calendar
Weather shows historical patterns, not a forecast. Holidays and events use the dates shown for 2027.
| Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|
| 180° | 279° | 379° | 479° | 579° | ||
| 679° | 779° | 879° | 979° | 1079° | 1178° | 1278° |
| 1378° | 1478° | 1578° | 1678° | 1778° | 1877° | 1977° |
| 2077° | 2177° | 2277° | 2377° | 2477° | 2577° | 2677° |
| 2777° | 2876° | 2976° | 3076° |
Afternoon high rain likely (25%+) local school holidays public holiday event
School-holiday dates for September 2027 aren't available in our data yet. A day without a school marker doesn't mean schools are open.
Afternoons cool from about 79°F (26°C) in the first week to 77°F (25°C) in the last. The chance of a wet day runs 4–16%.
Crowds, cost and getting there
Visitor season
Will it be busy?
Steady all year. September averages 93% of August's overnight stays per day. Overnight demand varies little across the year.
Overnight stays across Grande Lisboa do not measure queues, day visitors or congestion at individual sights.
Hotel price season
Will it be cheaper?
Well above usual. Historical regional hotel revenue (2024–2025 monthly average): €113 per guest-night. An average, not a booking quote.
Fewer overnight stays do not automatically mean cheaper rooms. Check actual quotes for your trip.
Historical hotel average
€113
2024–2025 monthly average; hotel revenue per guest-night; not a current booking quote. +28% vs this region's usual month.
Portugal as a whole
Well below EU average
2024 restaurants and hotels price level: 76 where the EU average is 100. A relative index, not a room rate.
Recorded US nonstop flights · 2024
Recorded this month
from Newark, Boston, Washington Dulles and New York JFK and 4 more; 2024 schedule, Eurostat
The historical regional amount comes from INE Portugal, Inquérito à Permanência de Hóspedes: hotel room revenue per guest-night; the country price level is national. Hotel averages are not live booking quotes.
Year-to-year variation
How much does September vary?
Across the recorded years
In the 15 years from 2011 to 2025, the month's afternoons averaged between 76°F (24°C) and 81°F (27°C); in 14 of them they were within 3°F (1.5°C) of the typical 78°F (25°C). Rain days ranged from 0 to 14; half the years had 1–4.
Rain days in each September
Rain days
2
at least 1 mm, typical year; about 6 in a wet year
Mostly sunny days
14 of 30
cloud cover under 30%
Years with a 95°F+ day
0 of 15
no September in the last 15 years had a day at or above 95°F (35°C)
Good weather days
29 of 30
rated very good or better
See every recorded SeptemberHistorical monthly averages, year by year Show detailsHide details
| Year | Afternoon high | Rain days |
|---|---|---|
| 2011 | 78°F | 1 |
| 2012 | 80°F | 4 |
| 2013 | 79°F | 5 |
| 2014 | 76°F | 14 |
| 2015 | 76°F | 1 |
| 2016 | 79°F | 1 |
| 2017 | 76°F | 0 |
| 2018 | 81°F | 1 |
| 2019 | 79°F | 2 |
| 2020 | 78°F | 3 |
| 2021 | 76°F | 4 |
| 2022 | 76°F | 4 |
| 2023 | 77°F | 6 |
| 2024 | 77°F | 2 |
| 2025 | 77°F | 2 |
Checked against official climate averages for Lisboa (Instituto Geofisico). How we check
Compare dates
August, September
or October?
| Typical conditions | Aug | Sep | Oct |
|---|---|---|---|
| Afternoons | 81°F | 78°F | 73°F |
| Sea | 65°F | 66°F | 65°F |
| Rain days | 0 | 2 | 8 |
| Overnight demand | 100% | 93% | 90% |
August: Warmer afternoons and fewer rain days than September. August guide →
October: Cooler afternoons and more rain days than September. October guide →
Overnight demand measures accommodation stays, not queues. Sea temperatures are monthly coastal averages.
Compare any of the 12 monthsChoose another month and compare it with September Show comparisonHide comparison
Yellow marks the top three months on the Balanced mix. September stays as your reference.
Hotel stays vary little through the year. No other scored month has a Weather score at least 1.0 point higher than September.
Your comparison
September or August?
Overnight stays vary little through the year.
Historical regional hotel revenue (2024–2025 monthly average): €84 per guest-night. An average, not a booking quote.
Read the August guide →| Typical conditions | September | August |
|---|---|---|
| Afternoons | 78°F | 81°F |
| Nights | 60°F | 60°F |
| Sea | 66°F | 65°F |
| Rain days | 2 | 0 |
| Visitor season | Steady all year | Steady all year |
| Overall / 10 | 8.1 | 8.4 |
| Month rank | #5 | #2 |
Every month, in detail Show detailsHide details
| Month | Overall | Rank | High | Low | Sea | Rain days | Weather | Visitor season |
|---|---|---|---|---|---|---|---|---|
| January | 7.2 | #12 | 60°F | 47°F | 59°F | 9 | 7.1 | Steady all year |
| February | 7.3 | #11 | 61°F | 48°F | 58°F | 8 | 7.3 | Steady all year |
| March | 7.4 | #9 | 64°F | 49°F | 58°F | 7 | 7.8 | Steady all year |
| April | 7.8 | #7 | 67°F | 52°F | 60°F | 8 | 8.8 | Steady all year |
| May | 8.2 | #3 | 72°F | 55°F | 62°F | 2 | 10.0 | Steady all year |
| June | 8.2 | #4 | 76°F | 58°F | 64°F | 1 | 10.0 | Steady all year |
| July | 8.4 | #1 | 80°F | 59°F | 65°F | 0 | 10.0 | Steady all year |
| August | 8.4 | #2 | 81°F | 60°F | 65°F | 0 | 10.0 | Steady all year |
| September | 8.1 | #5 | 78°F | 60°F | 66°F | 2 | 10.0 | Steady all year |
| October | 8.0 | #6 | 73°F | 59°F | 65°F | 8 | 9.6 | Steady all year |
| November | 7.4 | #8 | 65°F | 53°F | 63°F | 11 | 8.1 | Steady all year |
| December | 7.3 | #10 | 62°F | 49°F | 61°F | 7 | 7.4 | Steady all year |
Near here
Nearby places in September
Nearby regions, nearest first. Distances are centre to centre, as the crow flies; they are not road distances or journey times.
Setúbal PeninsulaPortugal · about 20 miles
Balanced Overall 8.5 · Excellent weather, 80°F (26°C) · Busy season · Cost cheap
Óbidos, Nazaré & the Tagus ValleyPortugal · about 40 miles
Balanced Overall 8.6 · Excellent weather, 82°F (28°C) · Busy season · Cost cheap
AlentejoPortugal · about 80 miles
Balanced Overall 7.9 · Very good weather, 85°F (29°C) · Moderate season · Cost moderate
Central Portugalabout 120 miles
Balanced Overall 8.7 · Excellent weather, 80°F (27°C) · Moderate season · Cost cheap
The AlgarvePortugal · about 130 miles
Balanced Overall 8.3 · Excellent weather, 82°F (28°C) · Busy season · Cost moderate
Elsewhere in Europe
Same dates, elsewhere in Europe
Lisbon's weather ranks 1 of 41 city regions this month. We found no city regions outside Portugal with similar weather and a quieter visitor season.
How we knowSources, regional scope & scoring method Show detailsHide details
Hotel stays are steady all year here: this month is 93% of the busiest and 17% above average. That counts overnight stays, not how busy the sights are.The figures cover the whole Grande Lisboa region, suburbs included. That means about 64,000 overnight visitors on a typical September night across the region, 16% of them from Portugal itself. Rentals booked through Airbnb, Booking, Expedia and Tripadvisor add up to 38,000 more: 60 for every 100 counted above. Some are the same properties counted twice.
| Climate suitability (HCI:Urban, 0–100) | 86 |
| How our weather was checked | Official climate averages for Lisboa (Instituto Geofisico) from the national weather service, every month: afternoon highs typically within 3°F (1.7°C), night lows within 2°F (1.3°C). |
| Tourist nights per 1,000 residents per day | 30 |
| Busiest month here | August · 32 |
| Visitors as share of people present | 2.9% |
| Rank among Europe's regions this month | 77th percentile |
| Domestic share of nights | 16% |
| Platform rental nights per 100 counted nights | 60 |
| Visitor share if every platform night were extra | 4.5% |
| Population used | 2.2 million |
| Statistical region | PT1A · Grande Lisboa |
Crowds: Eurostat nights spent at tourist accommodation, by month and NUTS 2 region, 2024–2025 average. Overnight visitors per night is the month's nights divided by its days; the per-1,000 figure is Eurostat's, against each year's population. Platform rentals: Eurostat nights booked via Airbnb, Booking, Expedia and Tripadvisor, 2024–2025 average, shown separately because some properties are in both counts. Weather: Holiday Climate Index computed from ERA5 reanalysis with daily highs, night lows and rain days corrected from open national weather-service station records, 2011–2025, population-weighted to the region; day-by-day figures are the same data averaged by date. Heat and rain odds are counted across those years. Sunrise and sunset: NOAA solar equations, local time. Prices: Eurostat price level index and HICP, national; the first figure is regional (INE Portugal, Inquérito à Permanência de Hóspedes: hotel room revenue per guest-night). Full method · this region's data.