Hurricane Polo is intensifying so fast forecasters expect a major hurricane by Tuesday

Hurricane Polo’s maximum sustained winds reached 85 mph Monday afternoon as a NOAA Hurricane Hunter aircraft found the storm rapidly intensifying off Mexico’s Pacific coast, and the National Hurricane Center’s 3 p.m. CST advisory said Polo is expected to become a major hurricane by Tuesday, with further strengthening likely through midweek. At that hour, Polo’s center sat about 290 miles southeast of Manzanillo and 195 miles southwest of Zihuatanejo, moving east-southeast at just 6 mph before an expected sharp turn toward the northwest and west-northwest late Tuesday into Wednesday. Forecaster Blake, who signed the advisory, wrote that Polo is undergoing an early-stage eyewall replacement cycle but that very warm water, light wind shear and a moist environment point toward a high-end rapid intensification event over the coming days.

A Tropical Storm Watch covers Mexico’s coast from Tecpan de Galeana to Punta San Telmo, and the center said that watch would likely expand westward later Monday or overnight. Hurricane-force winds extended up to 25 miles from Polo’s center and tropical-storm-force winds up to 70 miles, with the storm’s minimum central pressure measured at 974 millibars, or 28.77 inches.

Hurricane Hunter Data Put Polo’s Winds at 85 MPH and Falling Pressure

NOAA’s Hurricane Hunter aircraft measured flight-level winds up to 92 knots at an altitude of roughly half a kilometer, readings the center converted to a surface wind speed of near 85 mph for the 3 p.m. CST advisory. Forecaster Blake’s discussion said the plane found higher winds and lower central pressure on each successive pass, with pressure dropping roughly 1 millibar per hour. That reading came alongside two separate wind maxima the aircraft’s radar detected on the same pass, a signature of an early-stage eyewall replacement cycle even as Polo’s older, inner eyewall was already fading out.

The Forecast Track Sends Polo’s Winds to 165 MPH by Wednesday

The center’s own position table, built into Blake’s discussion, shows Polo’s maximum sustained winds climbing to 115 mph by Tuesday morning, 145 mph by Tuesday evening, 160 mph by Wednesday morning and peaking near 165 mph by Wednesday evening — a trajectory that would carry Polo well past the 111 mph threshold for a major hurricane within roughly a day of Monday’s advisory. Blake cautioned that a potential binary interaction with nearby Tropical Storm Odalys is helping widen the spread in the computer models beyond 72 hours, and that track details that far out remain, in the forecaster’s own word, “sketchy.” An increase in easterly wind shear during the medium-range period could also trim the intensity forecast somewhat, even though Polo is expected to stay a small, powerful hurricane throughout.

Rainfall Up to 12 Inches Threatens Guerrero and Michoacán Through Thursday

Rain, not wind, is the hazard the advisory frames as the most dangerous. Polo is expected to drop 4 to 8 inches of rain across coastal Guerrero and Michoacán through Thursday, with isolated totals reaching 12 inches capable of producing life-threatening flooding and mudslides in areas of steep terrain, while coastal Oaxaca, Colima and Jalisco face a lighter 3 to 6 inches over the same stretch.

Swells generated by the storm were forecast to reach the coast of southwestern Mexico starting Tuesday, a threat the center said is likely to cause life-threatening surf and rip current conditions well before Polo’s center comes anywhere close to land.

Manzanillo Faces the Highest Chance of Tropical-Storm-Force Winds

Among the specific coastal towns the center tracks individually, Manzanillo carried the highest risk in Monday’s probability table: a 47% cumulative chance of tropical-storm-force, 34-knot winds by Thursday evening, a 17% chance of 50-knot winds and an 8% chance of hurricane-force 64-knot winds. Zihuatanejo’s odds arrived sooner but stayed lower — a 21% chance of 34-knot winds by Wednesday evening — while Barra Navidad’s cumulative 34-knot probability reached 24% over the same window. The spread among those three towns shows how much Polo’s exact turn toward the coast, still projected for late Tuesday into Wednesday, will determine which stretch of shoreline actually takes the worst of it.

Farther offshore, the probability table also flagged Isla Socorro and the open-water point 20 degrees north, 110 degrees west, both of which carried roughly a 30% chance of tropical-storm-force winds by Friday as Polo’s projected track curves northwestward late in the five-day period. Those numbers matter less for anyone on land than they do for shipping routes and the Revillagigedo Islands, a reminder that a storm forecast to stay offshore of the Mexican mainland can still put open water at real risk days after the coastal threat has passed.

The center’s next advisory was due at 6 p.m. CST Monday, with a full update following at 9 p.m. Blake’s discussion left the door open for Polo to weaken slightly in the medium range if shear increases as expected, but for now the National Hurricane Center’s own forecast track shows nothing standing between Polo and major-hurricane status before Tuesday is over.

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This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.