Hurricane John has once more intensified, lashing Mexico’s southwestern coastline with heavy rainfall. This area, known for its bustling ports and popular tourist destinations, had already endured several days of severe weather brought on by the sluggish storm system.

Since Monday, John has menaced the coast, shifting between weakening and strengthening phases. During its path, it disrupted major shipping hubs, briefly closed airports, and tragically claimed five lives, many of them due to landslides triggered by the storm.

Meteorologist Jesse Ferrell from AccuWeather has labeled John as a “zombie” storm — a term for weather systems that weaken only to return to storm strength again. This term was popularized by the US National Weather Service in 2020 when Hurricane Paulette's remains revived near the Azores after initially hitting Bermuda.

One notable example of these "reviving" storms is Hurricane Ivan in 2004, which persisted for nearly a month. Ivan first devastated the Caribbean, dissipating before regenerating and striking the US, resulting in $26 billion in damages that year.

Atmospheric expert Christopher Rozoff, from the National Center for Atmospheric Research, explained John’s slow movement, noting that the absence of larger-scale weather patterns left it without the forces needed to guide it away.

According to Rozoff, this made John especially susceptible to “retracing its path over the sea, potentially re-strengthening and causing further havoc along the Mexican coast with more severe rainfall.”

By Thursday, John’s heavy rains were pounding the Mexican state of Guerrero after previously lashing the region earlier in the week, toppling trees, cutting power to thousands, and setting off deadly landslides that leveled homes.

Guerrero’s governor, Evelyn Salgado Pineda, urged residents on Thursday morning to exercise extreme caution, particularly after Acapulco’s beachfront eateries were hit hard the previous day by rising tides, and nearby roads were flooded from torrential rain. The resort town is still on a recovery path following major damage caused by Hurricane Otis the previous year.

As Hurricane John shifted to the northwest, it stalled about 55 miles (89 kilometers) off the shore of Lázaro Cárdenas, a key cargo port. By this time, it was generating sustained winds as fast as 75 mph (120 km/h), according to the US National Hurricane Center.

The Miami-based center predicted that John would skirt along Mexico’s southwestern coast, particularly impacting the states of Michoacán, Guerrero, and Oaxaca, with heavy rains expected to continue through Saturday.

“This prolonged downpour will likely result in destructive and life-threatening flash floods and mudslides,” the center warned.

The increase in human-induced climate change has led to more frequent occurrences of intense tropical storms, despite the global number of storms not rising year-to-year. Warmer oceans supply these systems with extra energy, intensifying their strength.

Alex DaSilva, a lead hurricane expert from AccuWeather, noted that both Hurricane John and Hurricane Otis rapidly gained power due to the unusually warm ocean waters, with some areas where John formed nearing 32°C (90°F), feeding the storm with ample energy.

Andra Garner, a meteorologist from Rowan University, added that those warm waters likely contributed to John’s ability to regenerate after its initial landfall.

Looking ahead, DaSilva stated it’s “highly probable” that we will continue to see rising sea temperatures, which could contribute to more frequent episodes of rapid intensification in future storms.