Weather Warning -Update-

Tropical wave #8 over Costa Rica

June 24th, 2025

04:50 p.m.

Diagnosis: The instability of Tropical Wave 8 has manifested itself with scattered heavy rains and downpours in various locations in the central and Pacific regions of the country. Rainfall with downpours accompanied by thunderstorms occurred in the Central Valley, mountains of the Central and South Pacific, and around the Gulf and Nicoya Peninsula.

The most significant accumulations so far are: 80 mm in La Unión de Cartago, 70 mm in La Paz, Mora, 65 mm in Santa Barbara, 80 mm in Los Chiles, 45 mm in San Ramón, 45 mm in Pérez Zeledón and Buenos Aires de Puntarenas, 30 mm in Braulio Carrillo National Park and Guápiles, and around Nicoya.

Forecast: For the remainder of the afternoon, heavy thunderstorms are expected in parts of the western Central Pacific, the South Pacific, parts east of the Gulf of Nicoya, and the northwestern-central part of the Northern Zone, as well as in low-lying areas of the Northern Caribbean and near the mountains of the Southern Caribbean (there is a high possibility that these precipitations will extend into the early evening, gradually decreasing in intensity). Accumulated rainfall is estimated between 25 mm and 50 mm, with maximums between 70 mm and 100 mm over periods of 6 to 12 hours.

In the Central Valley, variable rainfall is expected to continue with estimated amounts between 10 mm and 30 mm, with maximums of up to 60 mm over periods of 6 to 12 hours.

Tropical Wave 9 is forecast to enter the country between Wednesday and Thursday night. The continuous passage of tropical waves, combined with low-pressure systems associated with the Intertropical Convergence Zone, maintains a highly unstable environment, favoring the formation of large clouds and the presence of significant rainfall in different regions of the country.

Warning: Special attention should be paid to the Nicoya Peninsula, the entire Northern Zone, and the Caribbean in general, as well as the Central and South Pacific, due to the fact that these areas have very high soil saturation levels between 90 and 100%, which increases the vulnerability to the risk of incidents.

Due to the above, the IMN recommends:

• Caution due to possible sewer saturation in areas prone to flooding due to water accumulation.

• Thunderstorm prevention: If strong wind gusts occur or are perceived near storm clouds, it is recommended to seek shelter in a safe place, as tree branches, power lines, or other objects could fall. These gusts can reach up to 80 km/h in isolated cases.

• Stay informed through official channels: Twitter: @IMNCR, Facebook: Instituto Meteorológico Nacional CR, website: www.imn.ac.cr

Jose Valverde Mora

Meteorologist

DMSA-IMN