BOSTON, Oct. 11, 2011 — According to catastrophe modeling firm AIR Worldwide, with its outer rain bands already bringing heavy rainfall to Mexico’s southwest coast, Hurricane Jova is poised to make landfall as a strong Category 2 hurricane in Jalisco state this afternoon or early evening between the port city of Manzanillo in Colima state in the south and the resort city of Puerto Valarta in the north.
“Hurricane Jova is moving toward the northeast at about five mph, and this forward speed is expected to increase slightly today,” said Dr. Tim Doggett, principal scientist at AIR Worldwide. “A hurricane warning is in effect from Punta San Telmo northward to Cabo Corrientes, while a tropical storm warning is in effect from Lazaro Cardenas northward to south of Punta San Telmo, and north of Cabo Corrientes to El Roblito. Although Jova’s strength could fluctuate before landfall, at present it is expected to cross the coast in the hurricane warning area and make landfall by this afternoon or evening near its current 100 mph strength.”
As of the National Hurricane Center’s (NHC) 11:00 am (PDT) Advisory today, Hurricane Jova was about 110 miles southwest of Manzanillo (population 110,000) in Colima state, and about 175 miles south of Cabo Corrientes, the southernmost point of the Bahia de Banderas, where Puerto Vallarta (population 255,000) is situated. The NHC said that Jova has weakened since yesterday and that its maximum sustained winds, as monitored by an Air Force Reserve Hurricane Hunter aircraft, currently are 100 miles per hour with higher gusts, a strong Category 2 hurricane on the Saffir-Simpson wind scale. Earlier it had been thought that Jova might intensify to Category 4 strength.
If Jova remains at its current strong Category 2 intensity, damage in its immediate path at landfall could be considerable. According to AIR, structural damage to non-engineered buildings may occur, particularly to roofs, while windows and the cladding on engineered structures could be damaged by impact 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.
According to AIR, 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.
Dr. Doggett continued, “At Hurricane Jova’s expected wind speeds, many trees will likely be uprooted and snapped, blocking roadways or damaging homes and automobiles. Additionally, Jova is expected to bring torrential rainfall, with total accumulations of 6 to 12 inches over the coastal states of Michoacan, Colima, Jalisco, and Nayarit. The heaviest rainfall, up to 20 inches in isolated areas, can affect mountainous regions of the coast, creating a risk of flash-flooding and mudslides. Also, large and destructive waves are expected to batter a long stretch of coast, and, together with a dangerous storm surge especially to the east of where the storm center makes landfall, will probably cause widespread coastal flooding.”
In 1959 an unnamed hurricane made landfall in the same area where Hurricane Jova is about to come ashore. In Manzanillo, the 1959 hurricane destroyed 40 percent of all homes, 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.
“The 1959 hurricane made landfall as a Category 5 storm, however, while Hurricane Jova is expected to make landfall as an intense Category 2 storm at its strongest,” continued Dr. Doggett. “Additionally, Hurricane Jova currently is a rather small storm, with hurricane-force winds relatively confined to the center of the eye. Jova’s tropical storm-force winds extend outward up to 90 miles, so they will begin to interact with the mountains several hours before Jova makes landfall. Also, earlier today Jova experienced some eyewall disruption caused by upper-level wind shear. Consequently, Jova could possibly weaken still further before actually making landfall.”
Once Hurricane Jova does make landfall, it is expected to weaken rapidly: to wind speeds inland of about 75 mph within 24 hours, and down to 35 mph within 48 hours.
AIR is continuing to monitor Hurricane Jova and will provide additional information as events warrant.