Weather in Rome in December

Shoulder season. December sits in between. You will get good days and you will lose some. Highs sit at 13.7 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

December ranks 12 of 12 — near the bottom of Rome's year. April is the month that works, and the swing between the two is 25 points, which is a different holiday rather than a slightly better one.

Rain on 11 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Layers, and a genuinely waterproof outer — at 13.7 °C the difference between a good day and a miserable one is entirely down to what you are wearing.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest December day reached 20.1 °C and the coldest night fell to -3.1 °C, and the wettest single day dropped 44 mm — roughly 48% of the month's rain in one day.

December is moderately variable: 5 mm in the driest year against 233 mm in the wettest, around an average of 91 mm. Roughly two Decembers in three land near that average, and the third does something else entirely.

Wind is light at 8.3 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 81%, which at 13.7 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How December sits in the year

Temperatures hold steady either side: 18.1 °C in November, 13.7 here, 12.6 in January. Nothing about the timing within the month matters much.

Daylight in December

December sits at the dark end of Rome's year — 9.2 hours of daylight against 15.2 at midsummer, holding steady all month. Sightseeing days are genuinely shorter, and an itinerary built for summer will not fit.

Sea temperature

The sea sits at about 16.3 °C in December — cold — a quick dip rather than a swim, and a wetsuit if you are in for longer. The sea peaks at 25.8 °C in August and bottoms out at 14 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

December in Rome versus nearby

If Rome is one option among several, the nearby comparison is worth making. Naples is close enough to be a coin toss — within a degree on temperature, 1 day more rain. Positano is close enough to be a coin toss — within a degree on temperature, 2 days more rain.

So: December is a compromise. April is 25 points better and is what Rome is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Rome

See all twelve months in Rome, or where else to go in December.