Meteorologists are closely monitoring a low-pressure system off southern Mexico’s Pacific coast, which could develop into Tropical Storm Barbara — the second named storm of the 2025 Eastern Pacific hurricane season.
The first was Tropical Storm Alvin, which remained well offshore as it headed north toward the Baja California peninsula in the final days of May.
Alvin quickly weakened over cool ocean waters and had minimal impact once it reached land, although it did eventually bring flooding rain and thunderstorms to the deserts of the U.S. Southwest.
Barbara, as of Wednesday morning, was a system of showers and thunderstorms located 515 kilometers south-southeast of Salina Cruz, Oaxaca, with an 80% chance of cyclonic development within seven days, according to Mexico’s National Water Commission (Conagua).
The U.S.-based National Hurricane Center reported that the disturbance is moving west-northwestward at 16 km/h over waters warmed to 28°–29° Celsius, with moderate wind shear.
While there was a 10% chance of tropical storm formation within 48 hours, conditions are expected to have it top out as a tropical depression by the end of the week.
However, if its sustained winds do reach 65 km/h, it will be upgraded to Tropical Storm Barbara, or a hurricane if they reach 119 km/h.
Even without full cyclonic strength, the system is threatening coastal Guerrero, Michoacán and Oaxaca with heavy rainfall (75 to 100 mm) and potential landslides.
Soil saturation from recent rains raises risks of flash flooding and mudslides in mountainous zones, warned Conagua. No coastal watches are active, but residents are urged to monitor updates.
Persiste un 80 % de probabilidad para que se forme una zona de #BajaPresión con potencial ciclónico en los siguientes 7 días, al sur del #Pacífico mexicano. pic.twitter.com/eXPRad1kKK
— CONAGUA Clima (@conagua_clima) June 4, 2025
As noted in the recent article “Pacific hurricane season is officially underway. Are you prepared?” in Mexico News Daily, the 2025 season in the Pacific Ocean began May 15 and is forecast to produce 16 to 20 named storms, including four to six major hurricanes.
The season in the Atlantic began June 1, and both hurricane seasons will end Nov. 30.
Further information can be found in “How to deal with hurricane season in Mexico.”
Authorities emphasize preparedness, advising coastal communities to secure emergency kits and heed official alerts.
Forecasters warn that although early-season systems like Barbara often remain offshore, they can still drive dangerous rainfall.
With reports from Meteored, El Informador and N+
