Barbara and Cosme: New Tropical Storms Brewing in the Eastern Pacific

Tropical storms Barbara and Cosme taking shape

Invest 91E shows signs of development

NHC warns of possible impact

The eastern Pacific Ocean remains active with the formation of two weather systems that could become tropical storms in the coming hours.

Both meteorological phenomena are advancing with the potential to intensify and be named Barbara and Cosme, the next on the official 2024 storm list.

However, it’s still unclear which of the two disturbances will first be named Barbara and which will be designated as Cosme, the third named storm of the season.

Weather conditions suggest significant development over the weekend, prompting close monitoring by authorities and residents along Mexico’s coast.

Invest 91E under close watch

Barbara and Cosme taking shape as new tropical storms – Photo: Shutterstock

According to Fox Weather, one of these systems has already been classified as Invest 91E—a designation indicating special attention from the National Hurricane Center (NHC).

This group of storms is located offshore, southwest of Mexico’s coastline, and has shown signs of more rapid organization in the last 24 hours.

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The “invest” designation allows the NHC to gather advanced data and run computer models to predict the potential path and intensity of the system.

The other monitored system is located much closer to the Mexican coast and is also showing signs of strengthening.

Chances of development increase

Both areas currently have a 50% chance of developing within the next 48 hours, but the seven-day forecast presents a clearer picture.

Invest 91E has an 80% chance of evolving into a tropical storm over the next week, while the disturbance near the Mexican coast has a 70% chance.

According to the National Hurricane Center, “thunderstorm activity has increased on the eastern side of the disturbance” closest to the coastline.

That indicates growth in its organizational structure—an important step in its potential development into a tropical cyclone.

Possible effects on the Mexican coast

If this trend continues, Mexico could face direct impacts such as heavy rains, strong wind gusts, and high surf in parts of the country’s southwest region.

So far, no official warnings have been issued, but monitoring has intensified due to the systems’ progression.

The eastern Pacific basin has shown increased activity since the start of hurricane season on May 15.

That date marked the official beginning of cyclone tracking, and the first named storm was Alvin, which formed and quickly dissipated last week.

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The rapid development of Invest 91E contrasts with Alvin’s brief lifespan, possibly signaling a strengthening trend in the region.

NHC experts have noted that atmospheric conditions are currently favorable for tropical development—at least in the short term.

This is due to factors like ocean temperatures, mid-level atmospheric moisture, and low wind shear in the area.

While uncertainty remains about which system will become Barbara and which will be Cosme, it’s clear that both represent a potential developing threat, Fox Weather reported.