Costa Rica 7-day Weather Forecast: May 12 to 18, 2025

Recent Weather

With the start of May we’ve seen a typical rainy season pattern of heat building during the day and afternoon/evening thunderstorms. A few isolated storms have been quite heavy, resulting in localized flooding in the Central Valley and Nicoya Peninsula. The southern Pacific has already received some impressive amounts of rain for the season with over 15-inches (380 millimeters) in some spots.   

This Week’s Weather Outlook

Several key factors will influence conditions across the country this week, likely bringing more rain. We have morning warming, sea breezes bringing moisture in off the ocean, the passage of Tropical Wave #1, and the Intertropical Convergence Zone positioning itself near Costa Rica. These will all affect where and when it rains. 

The first tropical wave of the season is expected to arrive Tuesday. That will enhance the afternoon rains and may extend them the early evening. The Pacific, Central Valley, Northern Zone, and mountainous parts of the Caribbean have the highest probability of experiencing these showers.

Learn more about Tropical Waves with this post: Tropical Waves: What Are They & What to Expect in Costa Rica.  

The Costa Rica Meteorological Institute (IMN) says for the remainder of the week, the Intertropical Convergence Zone—a band of low-pressure—will become more active as it gradually approaches the country. This will significantly increase moisture levels, facilitating cloud formation and bringing afternoon and evening showers and thunderstorms, especially to the Pacific, Central Valley, North Zone, and Caribbean mountains. Some morning showers are also possible along the Pacific coast during the latter part of the week.

What to Expect Daily

Mornings

Partly cloudy conditions across the country, with possible early showers during the second half of the week, particularly in Pacific coastal areas.

Afternoons

Expect cloudy conditions with showers and thunderstorms in the Pacific, Central Valley, and Northern Zone, becoming more widespread later in the week. The Caribbean will remain partly cloudy with possible mountain showers.

Evenings

Cloud cover and showers will continue in Pacific regions, especially along the coast. The Central Valley, Northern Zone, and Caribbean mountains may experience scattered showers during the first half of the night.

Regional Temperature Outlook

The North Pacific will continue to have the highest daytime temperatures, while the Central Valley will experience the coolest overnight lows.