The beginning of the rainy season in Costa Rica During 2026 it will occur irregularly, according to the climate perspective of the National Meteorological Institute (IMN). The first rains will not be established uniformly across the national territory.
According to the IMN climate projectionpresented by meteorologist Karina Hernández Espinoza, the start of the season will occur between April and May, as usual, but with variations in the frequency and intensity of precipitation.
“For the rainy season, an irregular start is expected, as well as a closure with deficient conditions. The hurricane season is expected to be less active than normal, between 9 and 12 systems, when the normal or climatological is 14 systems,” said Hernández.
This condition implies that some regions could experience delays in the establishment of rainswhile others would record isolated events without consolidating the typical rainy pattern.
Throughout the rainy period, the country will face a precipitation deficit between 10% and 30% compared to historical values.
The most marked behavior will be observed towards the end of the season. The months of September, October and November The greatest reductions in rainfall will be concentrated, especially in the Pacific, the Central Valley and the north-western zone.
The start of the rainy season will be staggered by region:
- South Pacific: between April 27 and May 2
- Central Pacific: between May 2 and 10
- Central Valley: between April 29 and May 8
- North Pacific: between May 8 and 13
- North zone: between May 11 and 13
- Caribbean: no defined dry season
Furthermore, the less cyclonic activity scheduled for 2026 will limit the entry of systems that usually provide rain to the country, which will reinforce the deficit scenario.
The general picture points to a unstable start of the rainy seasonfollowed by a season with less accumulated than usual in much of the country.
