Weather in San José in December

A good month. December is a solid month to be in San José. Highs average 23.7 °C, lows 16.2 °C, and rain falls on 14 days — nothing in the month is working against you.

December ranks 4 of 12 in San José: past the worst of the year but short of February, which is the month to book if the dates are open.

This is persistent light rain rather than storms: 14 wet days but only 1 heavy ones. It rarely cancels anything outright, and it rarely fully clears either. A jacket beats an umbrella. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

Averages flatten a month, and this one hides a few things: it never really gets hot: not one day in an average December reaches 30 °C. Across the twenty years measured, the hottest December day reached 27.5 °C and the coldest night fell to 12.9 °C, and the wettest single day dropped 62 mm — roughly 87% of the month's rain in one day.

December is moderately variable: 17 mm in the driest year against 210 mm in the wettest, around an average of 71 mm. Roughly two Decembers in three land near that average, and the third does something else entirely.

Wind is light at 1.9 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 85%, high enough to notice on the warm days without dominating them.

How December sits in the year

Temperatures hold steady either side: 23 °C in November, 23.7 here, 24.4 in January. Nothing about the timing within the month matters much. Rain is the thing that moves: January brings 5 days less of it, so pushing the dates later buys drier weather.

Daylight in December

San José sits close enough to the equator that daylight barely moves all year — 11.5 hours in December, against a range of just 1.2 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: 12 °C between the year's warmest afternoons and coldest nights. At 1133 m the air is thin enough to matter — sun that burns faster than the temperature suggests, and nights that cool off quickly.

How busy it gets

Shoulder. The value months — prices ease off and you get the place closer to itself. December is the value pick for San José: it scores within 13 points of February without carrying February's prices.

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

December in San José versus nearby

If San José is one option among several, the nearby comparison is worth making. San Isidro is the weaker option in December — 2.4 °C warmer, 5 days more rain. Puntarenas is close enough to be a coin toss — 7.2 °C warmer, 7 days less rain.

So: December works, with February the better month by 13 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in San José

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