Costa Rica 7-Day Weather Forecast: August 18 to 24, 2025

Hurricane Erin’s Distant Influence and Active Conditions

Over the past few days, Costa Rica’s been experiencing some unexpected influence from Hurricane Erin, even though the storm is far to the east in the Atlantic. While hurricanes typically don’t directly impact Costa Rica due to geographical positioning, major storms like Erin can have far-reaching atmospheric effects across different regions.

Hurricane Erin’s circulation has helped alter the position of the Intertropical Convergence Zone (ITCZ), essentially “pulling” this weather-making system and affecting rainfall patterns across Central America. The hurricane’s influence has even drawn some moisture and rain patterns from the Pacific coast, contributing to the more active weather we’ve been experiencing. This demonstrates how interconnected weather systems can be, even with storms thousands of miles away.

The ITCZ will remain close to Costa Rica this week, combined with weak trade winds. Under these conditions, local factors such as daytime warming and sea breezes, working together with the ITCZ, will favor the formation of showers and thunderstorms during the afternoons.

Enhanced Activity Expected

This week’s pattern shows more significant activity than previous weeks, particularly in areas that have been relatively quiet recently. In the mornings, variable cloudiness will predominate, ranging from light to partly cloudy, allowing for rapid warm-up and warm temperatures across much of the country.

Because of that warm up, afternoons will have isolated showers and thunderstorms in the North Pacific (more significant than in previous days), the Central Valley, and mountains of the Northern Pacific and Caribbean. The Central and South Pacific will see rain and downpours that are more frequent and widespread too.

How This Week’s Pattern Could Play Out:

Monday-Tuesday active establishment: The enhanced ITCZ influence and Hurricane Erin’s distant effects create more widespread afternoon thunderstorm activity across multiple regions.

Mid-week consistency: Wednesday and Thursday maintain the active pattern with strong afternoon convection and morning warm-up cycles.

Weekend continuation: Friday through Sunday the pattern persists with afternoon thunderstorms and possible early evening rainfall extensions.

Daily Breakdown

Mornings

Variable cloud cover ranging from light to partly cloudy allows for rapid warming and warm temperatures across much of the country. This morning heating pattern is crucial for building the atmospheric instability that drives afternoon thunderstorm development.

Afternoons

Isolated showers and thunderstorms will develop in the North Pacific, the Central Valley, and mountains of the Northern Pacific and Caribbean. The Central and South Pacific will experience showers and downpours that are more frequent and widespread.

Evenings

The possibility of rain continues into the early evening hours, though it will tend to decrease in both intensity and coverage as the atmosphere cools down.

Temperatures

Temperature patterns feature warm morning conditions that rapidly heat up due to light cloud cover, followed by afternoon cooling where thunderstorms develop.

Here’s what we are looking at for high and low temperatures across Costa Rica’s different regions:

This forecast is based on the weekly outlook shared by Costa Rica’s National Meteorological Institute (IMN) and other sources.