The climate in Lisbon during September can be summarized as warm and dry.
September is in the fall / autumn in Lisbon and is typically the 3rd warmest month of the year. Daytime maximum temperatures average around a comfortable 27°C (80°F), whilst at night 17°C (63°F) is normal.
| Daytime temperature | 26.8°C 80.2°F | 
|---|---|
| Nightly temperature | 17.1°C 62.7°F | 
| Average temperature | 21.9°C 71.4°F | 
| Daily sunshine | 9.3 hrs | 
| Avg rainfall | 26 mm 1 ins | 
| Rainy days | 6 days | 
| Sea temperature | 20.4°C 68.7°F | 
| Humidity | 67% | 
| Windspeed | 12.2kph 8 mph | 
On average September is the 4th driest month of the year in Lisbon with around 26mm 1 inches of rain making it a dry time to visit. This rainfall is typically spread over 6 days, although this may vary considerably.
On the flip side this corresponds to an average of 9.3 hours of sunshine per day.
 
				 
						 
						The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Lisbon in September 2025.
Best places to visit in September
| Hottest month: | August | 28°C 82.4°F | 
|---|---|---|
| Driest month: | July | 4mm 0.2ins | 
| Sunniest month: | August | 11.8hrs | 
| Coldest month: | January | 14.7°C 58.5°F | 
| Wettest month: | November | 111mm 4.4ins | 
 
	 
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