This week marks an important transition as the hotter and drier weather we have been seeing becomes more unstable. That means the rhythm of afternoon rainfall will return to much of the country. Yup, after weeks of tracking the canicular period and its dry, stable conditions, we’re about to see more typical rainy season behavior this week.
Early this week, a humid and unstable environment will prevail across Central America due to the position of the Intertropical Convergence Zone near the country. This will generate scattered morning showers in the Caribbean and isolated afternoon thunderstorms, mainly in the Pacific and Central Valley regions.
Tropical Wave and Dust Activity
Tropical Wave #23 is expected to reach Costa Rica on Thursday, which will create a rainier day/afternoon. Looking toward the weekend and beginning of next week, there’s a possibility of more Saharan dust, but in lower concentrations. If that happens atmospheric humidity would decrease (soaked up by the dust) and reduce precipitation across the national territory again. We’ll watch it and keep you posted!
Early week humid conditions: Monday through Wednesday feature the most active weather as the Intertropical Convergence Zone brings scattered morning Caribbean showers and afternoon Pacific thunderstorms.
Thursday’s enhancement: Tropical Wave #23 reinforces rainfall patterns across multiple regions, marking the peak of this week’s wet weather.
Friday’s Mother’s Day: As Costa Rica celebrates Día de las Madres, expect continued active weather patterns with mostly cloudy conditions and scattered showers. Happy Mother’s Day to all those celebrating! 
Weekend dust influence: Possible low-concentration Saharan dust arrival could temporarily reduce humidity and rainfall, creating a brief dry period for weekend activities.
Variable cloud cover in the northern region and Caribbean with occasional rain near the coast and border areas during the early hours. The Central Valley and Pacific slope will see partly cloudy to cloudy conditions as moisture builds throughout the atmosphere.
Mostly cloudy conditions throughout the country, with isolated showers developing over mountain ranges, as well as the plains of the northern region and Costa Rican Pacific coast. This represents a significant change from recent weeks of scattered afternoon activity.
Mostly cloudy conditions continue throughout the country, with scattered showers along the Pacific coast and plains of the northern region as afternoon storm activity extends into evening hours.
Central Valley & Pacific: Experience the most dramatic change this week as afternoon thunderstorms return after weeks of limited/scattered activity. The Pacific coast will see increased evening shower activity as well.
Caribbean & Northern Zone: Maintain more consistent patterns with morning coastal showers and ongoing mountain range activity, though overall intensity increases as the ITCZ becomes more active.
Mountain Ranges: Across all regions, mountain areas will see increased isolated shower activity during afternoon hours as atmospheric instability increases.
Temperature patterns remain warm but may moderate slightly as cloud cover increases and rainfall activity returns across the country.
Here’s what we are looking at for high and low temperatures across Costa Rica’s different regions:
High: 31° (87.8°) | Low: 14° (57.2°)
High: 35° (95°) | Low: 19° (66.2°)
High: 33° (91.4°) | Low: 16° (60.8°)
High: 33° (91.4°) | Low: 16° (60.8°)
High: 30° (86°) | Low: 18° (64.4°)
High: 30° (86°) | Low: 17° (62.6°)
This forecast is based on the weekly outlook shared by Costa Rica’s National Meteorological Institute (IMN).
