Weather in Italy in September

September climate overview

Daytime highs across Italy in September run from 22.0°C (Lake Como) to 27.5°C (Sicily). In Sicily about 81% of September days reach 25°C. Nights average 17.2°C; the coldest 10% of nights in Lake Como fall to 11°C or below.

Rainfall in September

Expect around 9 rainy days (1 mm or more) in September, with Sardinia the driest (6 days) and Lido di Jesolo the wettest (11 days). The wettest September at Sicily between 1991 and 2020 was 2003 with 181 mm; the driest was 2001 with 0 mm.

Sea temperature

The sea averages 24.1°C around Italy in September - warmest at Sicily (25.2°C). That is comfortable for swimming.

Sunshine and daylight

Around 7.1 hours of sunshine a day on average, out of 12.2 hours of daylight (sunshine estimated from cloud cover).

September against the rest of the year in Italy

September is the 4th warmest month of the twelve in Italy. It is 4.5°C cooler than August and 4.4°C cooler in October. The hottest month here is August (29°C) and the coolest January (10°C).

Which part of Italy in September?

• Most sunshine: Sicily, 8.1 h a day.
• Driest: Sardinia, about 6 rainy days.
• Warmest sea: Sicily, 25°C.
• Hottest: Sicily, 28°C by day.
• Coolest (better for walking and cities): Lake Como, 22°C.

What to pack for Italy in September

Based on the averages: summer clothes for the day; a light jumper for evenings (17°C at night); a rain jacket - roughly 9 wet days; swimwear - the sea is 24°C.

Similar weather elsewhere in September

Within 1.5°C of Italy's September daytime average: Malaga (26°C, sea 22°C), Tenerife (25°C, sea 24°C), Zante (25°C, sea 25°C), Marbella (25°C, sea 21°C), Kos (25°C, sea 25°C). See the full ranking for September.

Choose Sicily for heat, Sardinia for fewer rainy days

Sicily is the strongest choice if warmth matters most, with daytime temperatures averaging 28°C and the sea at 25°C. That suits a swimming-focused holiday, though you may still want shade during the middle of the day. Sardinia offers a gentler balance: days average 26°C, the sea is 24°C and there are 6 rainy days, compared with Sicily's 7. Puglia is another option if you prefer warm rather than hot conditions, with 25°C days and 19°C nights. Local differences matter, though: Taormina averages 24°C by day and 10 rainy days, so do not assume every Sicilian destination matches the island-wide picture.

Cities are warm, but evenings call for a layer

Rome and Florence both average 25°C by day, making September a reasonable choice for spending plenty of time outdoors, provided you leave room for breaks when the sun feels strong. Their evenings are a different matter: Rome falls to 16°C and Florence to 15°C, so a light jumper or jacket earns its space in your bag. Naples combines the same daytime warmth with milder 18°C nights. For a cooler daytime option, Lake Como averages 22°C. Rome, Florence and Naples each have 9 rainy days, so choose plans that can move indoors rather than building the whole trip around dry weather.

Coastal stays still suit swimming, with a rain backup

Sorrento, Positano and the Amalfi Coast offer a balanced coastal option, with 24°C days, 19°C nights and sea temperatures of 24°C. Those conditions suit travellers who want time by the water without choosing the hottest destination. Swimming is a reasonable part of the plan, but the shared average of 9 rainy days means a beach-only itinerary has a catch. Pack swimwear and light daytime clothes alongside a light waterproof and an evening layer. The country average of 7.0 hours of sunshine leaves scope for time outdoors, but it is not a promise of clear skies throughout your stay. Keep swimming plans flexible around the weather.