Ivo — 2025

A small tropical cyclone formed from a low-pressure area along the monsoon trough southwest of Costa Rica and became a tropical depression near 1200 UTC on 6 August 2025 about 295 nautical miles southeast of Acapulco, Mexico. It moved generally west-northwestward parallel to the coasts of Central America and southwestern Mexico and remained close offshore until weakening to a remnant low by 0600 UTC 11 August. The system maintained tropical-storm status from 1800 UTC 6 August through 0000 UTC 11 August, with its center moving from roughly 96.5°W to about 118.2°W during that time. There were no recorded landfalls by Ivo on the Mexican coast. The cyclone passed just offshore of the southwestern coast of Mexico throughout its lifetime, and because of its small size and distance from shore, no coastal watches or warnings were issued. Ivo’s maximum sustained winds were estimated at 55 knots (about 63 mph) at 1800 UTC 8 August and 0000 UTC 9 August, with an estimated minimum central pressure of 998 mb. These values represent the peak intensity used in the official post-storm analysis; nearby scatterometer passes showed somewhat lower winds, but the small inner core seen in microwave imagery supported the higher peak estimate. Rainfall totals along portions of the southwestern Mexican coast were generally 1–3 inches, with isolated reports of about 5 inches. The Meteorological Service of Mexico and media reports indicated these rains produced minor freshwater flooding and a few mudslides in coastal areas; specific cities or counties were not listed in the report. No fatalities were reported in association with Ivo. Reported impacts were limited and described as minor — mainly localized flooding and small mudslides — concentrated along the southwestern coast of Mexico where the storm passed nearby. Forecasts anticipated the storm well in advance: Ivo was included in the 7-day Tropical Weather Outlook about 126 hours before formation and in the 48-hour outlook about 54 hours before formation. Official track forecast errors were larger than recent 5-year means at some forecast times, and several guidance models (including regional models HAFS-A and COAMPS-TC and the experimental GDMI) had lower average track errors. Official intensity forecasts tended to be biased high as Ivo did not become as strong as some forecasts predicted.