Hurricane Polo has rapidly intensified into one of the most powerful Pacific cyclones in decades, prompting alerts across several Mexican states and putting coastal communities on edge. The storm reached Category 5 status — the maximum level on the Saffir-Simpson scale, indicating sustained winds above 157 mph (253 kph) — on Tuesday, with peak winds recorded at around 168 mph (270 kph). It subsequently fluctuated to Category 4 before regaining some strength, a pattern forecasters say is likely to continue. The U.S. National Hurricane Center (NHC) in Miami described Polo as "extremely dangerous" and "truly remarkable" in the speed of its intensification, noting it escalated from tropical storm to Category 5 in approximately 36 hours — placing it among the fastest-intensifying storms ever recorded in the Pacific basin, alongside Hurricane Patricia (2015) and Hurricane Otis (2023).
As of Wednesday, Polo was located roughly 165 miles (266 kilometres) south of Zihuatanejo, a port city in the southwestern state of Guerrero, and was moving slowly northward before an expected turn to the northwest. The NHC forecast it would track parallel to Mexico's Pacific coastline rather than making direct landfall, though the agency cautioned that uncertainty remained about how close the storm would pass. Hurricane-force winds extend up to 40 miles (65 kilometres) from the centre, and tropical storm conditions were expected along the coasts of Guerrero, Michoacán and Colima states. Waves of 7 to 9 metres were forecast for those states, with smaller swells reaching Jalisco and Oaxaca. Mexican authorities shut ports in Guerrero and Michoacán, suspended school classes in coastal municipalities, and the U.S. Embassy issued an alert urging American citizens to stay away from beaches and waterways.
The storm's extraordinary intensification has been attributed to this year's powerful El Niño weather phenomenon. El Niño — a periodic warming of central and eastern Pacific Ocean surface temperatures — creates warmer seas and favourable wind patterns that act as fuel for Pacific hurricanes. Sea surface temperatures in a key Pacific region were recorded at 3.05°C above average in mid-September, surpassing the previous record set during the 2015 El Niño event. Scientists are informally calling this a "super El Niño," and its effects are already being felt globally. Philip Klotzbach, a research scientist at Colorado State University, noted that all the conditions needed for rapid intensification were present. Polo is the third Category 5 storm of this Pacific season, following Genevieve and Lowell.
Even without a direct landfall, the risks to coastal populations remain serious. Forecast rainfall of 3 to 6 inches (8 to 15 centimetres) in Guerrero and Michoacán could trigger flash flooding and mudslides, and hazardous rip currents and rogue waves pose a threat along the broader coastline. In Lázaro Cárdenas, a port city in Michoacán, residents were already bracing for impact as strong waves reached the shore. "We're worried and trying to protect our businesses," said Concepción López Villegas, a restaurant owner who has worked for decades to build her seaside establishment. "From one moment to another, it could be destroyed." Mexican President Claudia Sheinbaum urged coastal residents to remain vigilant, while emphasising that a direct strike did not appear likely for now. The same El Niño pattern suppressing Pacific storm activity is meanwhile producing a historic lull in the Atlantic, where no hurricanes have formed so far this season — a record since satellite monitoring began.