According to catastrophe modeling firm AIR Worldwide, Hurricane Bud, the first Category 3 hurricane on record to form in the eastern Pacific so early, is poised to make landfall as a weakening Category 1 hurricane in Mexico’s Jalisco state sometime tonight. Landfall is expected to be somewhere between the port city of Manzanillo in Colima state in the south and the resort city of Puerto Vallarta in the north. The coastline where Bud is expected to cross over to land is rugged and relatively unpopulated, but dotted with popular beach resorts.
As of the National Hurricane Center’s (NHC) 11:00 am (PDT) Advisory today, Hurricane Bud was about 75 miles west of Manzanillo (population 110,000) in Colima state, and about 105 miles south of Cabo Corrientes, the southernmost point of Bahia de Banderas, where Puerto Vallarta (population 255,000) is situated. The NHC said that Bud has weakened since its wind speeds peaked at 115 miles per hour last night (Thursday) and that its maximum sustained winds currently are 100 miles per hour with higher gusts—a weak Category 1 hurricane on the Saffir-Simpson wind scale.
“If Hurricane Bud is still a hurricane when it makes landfall tonight, it will be only the second time in history that that an eastern Pacific hurricane will have struck Mexico so early as the month of May,” said Dr. Tim Doggett, principal scientist at AIR Worldwide. “The other May landfall was Hurricane Agatha on May 24, 1971—which struck the same stretch of coast that Bud is approaching. Last year, Hurricane Jova also made landfall in this region, and in 1959 an unnamed hurricane also made landfall here. However, the 1959 hurricane—which made landfall as a Category 5 storm—destroyed 40 percent of all homes in Manzanillo, and throughout the area of its impact it killed at least 1,000 people directly and perhaps twice that number, largely through flooding. It remains one of Mexico’s worst natural disasters of the last half-century.”
“Hurricane Bud is moving toward the north at about seven mph, but this forward speed is expected to slow today as the storm approaches Mexico’s coast. A hurricane warning is in effect from Manzanillo northwestward to Cabo Corrientes, while a tropical storm warning is in effect from Punta San Telmo westward to east of Manzanillo. Aircraft reconnaissance information gathered this afternoon indicates that Bud may already have weakened substantially. It is expected to continue to weaken as it approaches the coastline, but it could still reach the coast at or near hurricane strength with winds of 75 mph or more.”
According to AIR, damage in Hurricane Bud’s immediate path at landfall is not expected to be severe if current forecasts of the hurricane’s gradual weakening prove true. Minor damage to non-engineered buildings may occur, particularly to roofs, while windows and the cladding on engineered structures could suffer minimal damage by impacts from debris. Most insured residential structures on Mexico’s west coast are made of confined masonry, which performs better than plain masonry under lateral wind loads because of its use of bond beams and columns.
Dr. Doggett continued, “Commercial properties tend to be constructed of confined masonry or reinforced concrete. At present, however, a single national building code for structural design does not exist in Mexico. The enactment and adoption of building codes are subject to the actions of separate government departments in each of the more than 2,400 municipalities. At the same time, a large percentage of the residential housing built in Mexico every year—perhaps as high as 50%—is constructed without building permits, and thus may be more prone to being damaged.”
According to AIR, at Hurricane Bud’s expected wind speeds, some trees likely will be downed or have branches broken, blocking roadways or damaging homes and automobiles. More particularly, especially because of the storm’s slow forward speed once it makes landfall, Bud is expected to bring total rainfall accumulations of six to ten inches over the coastal states of Michoacan, Colima, Jalisco, and Nayarit. The heaviest rainfall—as much as 15 inches in isolated areas—can affect the region’s mountainous areas, creating a risk of life-threatening flash-floods and mudslides. Also, a dangerous storm surge is expected to produce significant coastal flooding near and to the east of where Bud’s center makes landfall. Near the coast the surge will be accompanied by large and damaging waves. Already, swells generated by the hurricane are affecting portions of Mexico’s southern and southwestern coasts, likely producing life-threatening surf and rip-current conditions.
At present, according to the National Hurricane Center, Hurricane Bud’s cloud pattern “has basically become an amorphous blob of convection” and the storm is continuing to weaken. As Bud approaches the coastline of Mexico, the NHC forecast expects it to decay rapidly. Its outer winds will begin to interact with the high terrain even before it reaches land, which in turn will act to decouple the storm’s mid-level circulation from its surface circulation. Bud is then forecast to become a remnant low and then to dissipate over the next days while drifting slowly southwestward away from the coast.