Weather in Cusco in December

Shoulder season. December sits in between. You will get good days and you will lose some. You should expect rain on 21 days of the month, which is more days wet than dry.

December ranks 10 of 12 — near the bottom of Cusco's year. August is the month that works, and the swing between the two is 36 points, which is a different holiday rather than a slightly better one.

Rain on 21 of the month's 31 days, 4 of them heavy. At that frequency a wet-weather backup is not a contingency, it is the itinerary — book the indoor things first and treat the clear days as the bonus. Pack for 17.5 °C days and 6.8 °C nights; the spread matters more here than any single number.

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 22.5 °C and the coldest night fell to 4.2 °C, and the wettest single day dropped 75 mm — roughly 55% of the month's rain in one day.

December is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest December on record still delivered 303 mm against 77 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 137 mm average is a reasonable planning figure, not a promise.

Wind is light at 6.5 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 80%, high enough to notice on the warm days without dominating them.

How December sits in the year

Temperatures hold steady either side: 18.4 °C in November, 17.5 here, 16.9 in January. Nothing about the timing within the month matters much. Rain has already shifted: 9 days more than November had.

Daylight in December

Cusco sits close enough to the equator that daylight barely moves all year — 12.9 hours in December, against a range of just 1.6 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

An inland climate

Despite being inland, the year stays fairly even: 13.5 °C between the year's warmest afternoons and coldest nights. At 3312 m, altitude is doing as much work here as latitude: thinner air means fierce sun by day and heat that leaves the moment it sets.

How busy it gets

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

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

December in Cusco versus nearby

If Cusco is one option among several, the nearby comparison is worth making. Arequipa is a better bet in December — 8.2 °C warmer, 16 days less rain. Lima is a better bet in December — 11.7 °C warmer, 21 days less rain.

So: December is a compromise. August is 34 points better and is what Cusco 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 Cusco

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