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Water temperatureEnter

Italy: where to swim in September?

Italy, in September: the sea is at 25.2 °C on average along the coast, from 24.0 °C to 26.3 °C depending on the spot. Where the water is warmest (26.3 °C), it is warm. Ideal for long swims and for being in the water all day.

Sea temperature, month by month

MonthAverage temperatureDepending on the spotWhere it is warmest
January14.9 °C14.1 °C – 15.7 °Ccool
February14.3 °C13.6 °C – 15.1 °Ccool
March14.1 °C13.4 °C – 15.0 °Ccool
April15.5 °C14.7 °C – 16.1 °Ccool
May17.9 °C17.3 °C – 18.5 °Ccool
June22.5 °C21.9 °C – 23.3 °Cwarm
July25.6 °C24.5 °C – 26.6 °Cwarm
August26.5 °C25.7 °C – 27.4 °Cvery warm
September25.2 °C24.0 °C – 26.3 °Cwarm
October22.2 °C20.5 °C – 23.5 °Cwarm
November19.4 °C17.9 °C – 20.6 °Cpleasant
December16.5 °C15.4 °C – 17.6 °Ccool

Compared with August, the water cools down by 1.3 °C in September. The warmest month: August (26.5 °C). The coldest: March (14.1 °C).

Nearby, in September

And right now?

For the temperature measured right now, station by station and to the hour: Italy: water temperature

Frequently asked questions

What is the sea temperature in September?

Italy, in September: 25.2 °C on average along the coast, from 24.0 °C in the coolest waters to 26.3 °C in the warmest (average of the years 2011 to 2025).

Can you swim in September?

Where the water is warmest (26.3 °C), it is warm. Ideal for long swims and for being in the water all day.

What is the best month for swimming?

The water is warmest in August (26.5 °C on average) and coldest in March (14.1 °C). Where the water is warmest, it goes above 20 °C in these months: June, July, August, September, October, November.

Where is the water warmest in September?

The warmest in September: Croatia (24.1 °C), France (20.1 °C), Germany (17.0 °C). The coolest: Denmark (16.3 °C).

Where do these temperatures come from?

These are averages of the sea surface temperature from 2011 to 2025, computed from NOAA satellite images (OISST, one value about every 50 km), in a 100 km strip along the coasts of the main country: distant territories (overseas, remote islands) are not counted. It is an estimate, not a measurement taken at the beach: lakes and rivers are not included.

← August · October → · Warmest water today