Costa Rica Weather by Month: When the Dry Season Really Starts, and How Wet the Green Season Gets

What is the weather in Costa Rica, in one minute?

Costa Rica's Pacific side has two seasons, and they are not subtle. From December to March it is hot, sunny and close to dry: Tamarindo gets 16 mm of rain in December and then only 3 mm, 1 mm and 3 mm from January to March. From May to November it rains heavily, with 167 to 391 mm a month in Tamarindo and 306 to 611 mm in Santa Teresa. April is the switch, when the first storms arrive and the dry heat peaks just before them.

Here is the year for Tamarindo, the north-west coast:

Averages 2015-2025 · Source: Open-Meteo, CHIRPS · How we measure

Read the rain line first: almost nothing for four months, one step up in April and a long wet block with a peak in October. The temperature band is nearly flat: Costa Rica changes with rain, not with heat. For one month at a time, the Tamarindo, Santa Teresa and San José pages are faster.

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When is the dry season in Costa Rica, exactly?

December to March, with a short lead-in at each end. December is already dry on the coast (16 mm in Tamarindo, 32 mm in Santa Teresa, 30 mm in San José) but not as dry as January, and about half the sky is still cloud. January to March is the clean window: 1 to 3 mm in Tamarindo, 5 to 8 mm in Santa Teresa and 9 to 13 mm in San José, with the clearest skies of the year.

Heat builds through the window. Tamarindo's high climbs from 32° in January to 34° in March, and humidity stays low at about 59 to 64 percent. That is the best stretch for a long beach stay, and also the most expensive and most booked. If you work from a laptop in the sun, March is the hottest of the dry months and the one to plan around with air conditioning or a shaded desk.

How wet is the green season, really?

Wetter than the name suggests. "Green season" is the tourism word for May to November. Our figures say rain is 230 mm in May and 329 mm in June in Tamarindo, with cloud over 80 to 88 percent of the sky. September is 271 mm, October 391 mm, and only July (167 mm) gives a lighter break.

In Santa Teresa it is worse: 335 mm in May, 480 mm in September and 611 mm in October. The chance of rain on a given day in our data is 72 to 82 percent in the peak months in Santa Teresa and 72 to 84 percent in Tamarindo. We hold monthly totals, not the time of day, so we cannot tell you the rain comes only in the afternoon; plan for wet spells that can last days.

July is the lighter month of the wet season at Tamarindo (167 mm, against 329 mm in June and 242 mm in August), a dip known locally as the veranillo, the "little summer". Do not count on it: it is a dip within a wet season, not a dry spell.

Pacific coast or San José?

San José is the same two seasons at a lower temperature. It is 1,100 m up, so highs of 24° to 27° and lows of 16° to 17°: comfortable days and cool nights with no need for air conditioning. In the dry months it gets 9 to 13 mm a month, in the green season 164 to 319 mm, so it is clearly less wet than Santa Teresa and close to Tamarindo, but still a rainy city for half the year.

Choose by what you need: coastal heat and surf in the dry months, the capital for a cooler base with better connections. The wet season is a poorer trade on the coast than in the city, where you can stay indoors and work through it.

Tamarindo or Santa Teresa?

Tamarindo, in the north-west, is the drier of the two in every month in our data: 1 mm against 5 mm in February, and 391 mm against 611 mm in October. It is also hotter, 34° in March against 31°. Santa Teresa, at the southern tip of the Nicoya peninsula, is one to four degrees cooler, more humid (70 to 77 percent in the dry months, 88 to 91 in the wet) and gets noticeably more rain from April on.

If rain is what you are avoiding, choose Tamarindo for the shoulder months. If you are coming for the green season on purpose, check the sea and the roads as well as the weather. Here are the three places side by side in a dry, a switch and a wet month:

Who should go when?

• December to March: the dry-season trip. Best for first-time visitors, surf and yoga stays and anyone who wants to be outside every day. Book early; January and February are the surest.
• April: a gamble. Tamarindo's rain is 31 mm and Santa Teresa's 83 mm, so the first storms come, and it is nearly as hot as March, the hottest month on the coast (34° in Tamarindo).
• May to July: the wet season is established (167 to 370 mm a month on the coast). June is already one of the wettest months; July is the lighter dip.
• August to November: the heart of the green season. September and October are the wettest months. November eases (222 mm in Tamarindo, 339 mm in Santa Teresa) and is the way back to the dry window.

If you are choosing between warm places for the winter, see where is warm in January, in February and in March for the full ranking, where Costa Rica's dry coast competes with Asia and the Canary Islands.

This page covers weather only. It does not cover prices, internet, surf or the Caribbean coast, which has a different rain pattern and is not tracked here.

Which base?

• Tamarindo

  1 mm in Feb0 rain days in Feb33° high in Feb

  The north-west coast: the driest and hottest of the three. Chips show February.

  Suits: dry-season beach stays and the shoulder months

• Santa Teresa

  5 mm in Feb1 rain days in Feb31° high in Feb

  The southern Nicoya tip: a few degrees cooler and more humid. More rain than Tamarindo from April.

  Suits: surf and yoga in January to March

• San José

  9 mm in Feb2 rain days in Feb26° high in Feb

  1,100 m up: no air conditioning needed. Same two seasons, at a lower temperature.

  Suits: a cooler base with better connections, and working through the wet months indoors