Subseasonal forecast

Valid from jun 22-jul 6 , 2025

(4 weeks)

General comment:

In June, the tropical cyclone season begins in the Atlantic and Caribbean Sea; this year the first weeks of the month will be rainy in the Pacific region. The second half of June is expected to be less rainy, in addition to moderate wind conditions.

Fig. 1. Weekly precipitation forecast by region for the next 4 weeks.

1.Forecast from jun 9-15, 2025

During the week it will remain rainy in most of the Central and South Pacific, the Caribbean will tend to have less rainfall, favoring a dry scenario compared to the rains of the season (amounts in the Pacific of 40-90 mm per week, Caribbean and North Zone 40-70 mm, Central Valley 40-75 mm).

Probability of extreme event: low (around 20%)
Prognosis uncertainty: medium

2. Forecast from jun 16-22, 2025

Moisture levels will continue to rise in the Caribbean, favoring seasonal rainfall, although a bit of rain in the early days. Rainfall in the Central Pacific, South Pacific, and Central Valley will also be normal (60-120 mm weekly in the Pacific, 40-90 mm in the Caribbean and North Pacific, and 40-90 mm in the Central Valley).

Probability of extreme event: low (around 20%)
Prognosis uncertainty: medium

3. Forecast from jun 23-28, 2025

This week, humidity levels will remain low, with the sun shining brightly in the center and north of the country. Clear conditions will favor warmer-than-normal temperatures. The Pacific will be drier than normal, while the rest of the country will experience normal conditions.

Probability of extreme event: low (around 30%)
Prognosis uncertainty: medium

4. Forecast from jun 29-Jul 6, 2025

Very weak trade winds and the presence of the Intertropical Convergence Zone over the country. The Intertropical Convergence Zone is expected to favor rainy conditions throughout the Pacific and Central Valley.

Probability of extreme event: low (around 20%)
Prognosis uncertainty: high

Forecast of extreme events from jun 9-15, 2024

This week, there is a moderate possibility of cyclogenesis, meaning a low-pressure system could form north of Panama, generating rainy conditions in the southern Pacific of Central America. There is a high possibility of a rainy scenario in Costa Rica and a very low possibility of direct impact from a tropical cyclone.

Fig. 2. Forecast of extreme events for the next 2 weeks (training areas).

Forecaster: Daniel Poleo
Maps: Nury Sanabria Valverde
Unidad de aplicaciones climáticas
Departamento de Desarrollo/IMN

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