This post is an overview of the weather in Lisbon during September, including temperatures and rain forecasts, as well as things to do.
Daytime high temperatures tend to average near 28 C (82 F) early in the month falling to about 24 C (76 F) near the month’s end.
On average, about 4 days will see afternoon high temperatures reaching at least 32 C (about 90 F) but mostly during the early part of the month.
The record high temperature reported in Lisbon during September was 37.1 C (98.8 F).
Late night and early morning low temperatures will average near 18 C to 19 C (about 65 F) early in the month gradually dropping closer to 16 C (about 61 F) near the end of the month.
A few of the cooler mornings, especially late in the month, can dip down to near 14 C (about 57 F).
The record low temperature recorded in Lisbon during September was 10.7 C (51.3 F).
Lisbon offers plenty of sunshine this month with about 19-23 days experiencing sunny or at least partly sunny skies.
Some rain will fall on about 5-8 days this month, however, only 3-4 days will record at least 1 mm (0.04 inches) and only 1 day receiving 10 mm (0.40 inches) or more.
Daylight lasts about 13 hours on September 1st but decreases gradually to about 11.8 hours by the 30th.
Humidity levels range from comfortable to somewhat humid with about 4-5 days being considered muggy.
Wind conditions during September are mostly gentle averaging 12-19 kph (8-12 mph) but occasionally become moderate at 20-28 kph (13-18 mph).
Light summer clothes work well from late morning through the afternoon, however, bring some heavier fall clothes, a windbreaker, and a couple of sweaters for those cooler evenings and early mornings.
We suggest a windbreaker from Columbia because it’s breathable and will work even on warmer days. It also has a packable hood!
A travel scarf is multi-use and great for when the temperatures can fluctuate on a trip.
With moderate weather, most of the year-round activities can be enjoyed in September. Some things to do this month are:
Find out about the best things to do in Lisbon at any time of year.
TIP: Many of the museums, tours, and historic locations one can visit this month are included with at least one Lisbon tourist attraction discount pass which can save you anywhere from 20% – 40% off general admission prices on average.