Weather Warning | Update

Rains of varying intensity in recurring sectors

June 15, 2025

5:35 p.m.

Diagnosis: The unstable pattern persists over the country, associated with the proximity of the Intertropical Convergence Zone, high temperatures, and the presence of a low-pressure system located off the coasts of Guanacaste and Nicaragua, which favors a constant flow of moisture from the ocean into the country. The most significant accumulations since 7:00 a.m. are:

• Northern Zone between 20 and 40 mm, with maximums between 55 and 70 mm around Sarapiquí.
• Northern Caribbean between 20 and 55 mm, with the most significant downpours around Guápiles.
• Northern Pacific between 20 and 30 mm, with maximums between 30 and 55 mm in northern parts of the region.
• Central Valley between 10 and 20 mm, with maximums between 20 mm and 40 mm in the mountains in the northeast of the region.
• Central and South Pacific: 10 to 35 mm, with a maximum rainfall in the canton of Osa.
• Rainfall in the South Caribbean is below 10 mm.

Forecast: Rain and downpours with thunderstorms will continue for the rest of the afternoon. There is a high possibility of this pattern continuing overnight in the northern zone, the western North Caribbean, the North Pacific, and the South Pacific. A gradual decrease in rainfall is expected for the rest of the country during the early evening hours, with light to moderate drizzle and rain. In particular, for the North, Central, and South Pacific, accumulated rainfall is estimated at between 10 mm and 30 mm, with maximum rainfall between 30 mm and 50 mm over periods of 6 to 12 hours. In the northern zone and western North Caribbean, accumulated rainfall is expected at between 15 mm and 35 mm, and maximum rainfall between 35 mm and 60 mm over periods of 6 to 12 hours. In the Central Valley and Southern Caribbean, rainfall accumulations between 10 mm and 20 mm are expected, with maximums between 20 mm and 40 mm in the Central Valley over periods of 6 to 12 hours.

Tropical wave 6 is expected to enter on Monday, June 16th. Its axis is currently located at 81°W. This system will increase rainfall throughout Monday and early next week.

Warning: Special attention should be paid to the Nicoya Peninsula, the mountains of the Northern Zone, the Sarapiquí Basin, and the South Pacific, as these areas have very high soil saturation levels, between 85% and 95%, which increases the risk of incidents.

Due to the above, the IMN recommends:

• Caution due to sewer saturation in areas prone to this type of flooding.
• Prepare for thunderstorms and seek shelter in a safe place if strong wind gusts occur or are perceived near storm clouds, due to the potential for falling tree branches, power lines, and other conditions. These gusts can reach 80 km/h in some isolated cases.
• Stay informed through social media: Twitter: @IMNCR, Facebook: Instituto Meteorológico Nacional CR, and the website: www.imn.ac.cr

Paulo J. Solano S. | Meteorologist | DMSA-IMN

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