September weather forecastNaples, Italy
September
Weather in September
September in Naples brings the gradual ending of summer and the incipient whispers of autumn. While the heat of the summer subsides, rainfall begins to increase, jumping from 8mm (0.31") in August to 45mm (1.77"). The sun still generously shines, but the days noticeably become shorter. Despite indicating the start of rainy season, it retains enough sunny weather to enjoy outdoor activates.Temperature
September sees a slight reduction in average high-temperature, with a shift from a tropical 30°C (86°F) in August to a moderately hot 25.8°C (78.4°F). In Naples, the nighttime temperature averages to an enjoyable 19.5°C (67.1°F) during September.Humidity
In September, the average relative humidity in Naples is 64%.Rainfall
In September, the rain falls for 11.5 days. Throughout September, 45mm (1.77") of precipitation is accumulated. In Naples, during the entire year, the rain falls for 139.4 days and collects up to 569mm (22.4") of precipitation.Snowfall
In Naples, snow does not fall in March through December.Sea temperature
In September, the average sea temperature in Naples is 24.8°C (76.6°F).Note: When thinking about a swim in 24.8°C (76.6°F) waters, consider your cold tolerance, the day's sunshine, wind, and air temperature. It is a fun fact that Olympic swimmers dive into waters of 25°C (77°F) to 28°C (82.4°F).
Daylight
The average length of the day in September is 12h and 28min.On the first day of the month, sunrise is at 06:30 and sunset at 19:35. On the last day of September, in Naples, sunrise is at 06:58 and sunset at 18:46 CEST.
Sunshine
In September, the average sunshine in Naples is 10.9h.UV index
In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for the ordinary person.Note: In September, the average maximum UV index of 5 translates into the following recommendations:
Undertake precautions - It is suggested to shield oneself from sunburn. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun. Be careful! The Sun's UV radiation is accentuated by reflecting off sand and water.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Naples, Italy
- Average high temperature in September: 25.8°C
The warmest month (with the highest average high temperature) is August (30°C).
The month with the lowest average high temperature is January (12.3°C).
- Average low temperature in September: 19.5°C
The month with the highest average low temperature is August (22.7°C).
The coldest months (with the lowest average low temperature) are January and February (7.8°C).
Average pressure in September
Naples, Italy
- Average pressure in September: 1015.6mbar
The month with the highest atmospheric pressure is December (1018.4mbar).
The month with the lowest atmospheric pressure is April (1014mbar).
Average wind speed in September
Naples, Italy
- Average wind speed in September: 10.1km/h
The windiest month (with the highest average wind speed) is February (13.9km/h).
The calmest month (with the lowest average wind speed) is August (8.7km/h).
Average humidity in September
Naples, Italy
- Average humidity in September: 64%
The months with the highest relative humidity are January and November (73%).
The month with the lowest relative humidity is August (61%).
Average rainfall in September
Naples, Italy
- Average rainfall in September: 45mm
The wettest month (with the highest rainfall) is November (114mm).
The driest month (with the least rainfall) is August (8mm).
Average rainfall days in September
Naples, Italy
- Average rainfall days in September: 11.5 days
The month with the highest number of rainy days is January (15.4 days).
The months with the least rainy days are July and August (5.2 days).
Average snowfall in September
Naples, Italy
- Average snowfall in September: 0mm
The months with the highest snowfall are January and February (2mm).
The months with the least snowfall are March, April, May, June, July, August, September, October, November and December (0mm).
Average snowfall days in September
Naples, Italy
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (0.4 days).
The months with the least snowfall days are March, April, May, June, July, August, September, October, November and December (0 days).
Average sea temperature in September
Naples, Italy
- Average sea temperature in September: 24.8°C
The best month for swimming (with the highest average sea temperature) is August (26°C).
The coldest month (with the lowest average sea temperature) is February (13.9°C).
Average daylight in September /
Average sunshine in September
Naples, Italy
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 10h and 54min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 5h and 36min).
Average sunshine days in September
Naples, Italy
- Average sunshine days in September: 15.6 days
The month with the most sunshine days is July (24 days).
The month with the least sunshine days is February (11.1 days).
Average UV index in September
Naples, Italy
- Average UV index in September: 5
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February and December (UV index 3).
Average cloud cover in September
Naples, Italy
- Average cloud cover in September: 19
The month with the most cloud cover is January (Cloud cover 41).
The month with the least cloud cover is August (Cloud cover 9).
Average visibility in September
Naples, Italy
- Average visibility in September: 10km
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
