Hurricane Omar

Landfall | Summary
Posting Date: October 16, 2008, 8:00:00 AM

At 3:00 AM EDT, Thursday, October 16, Hurricane Omar was tracking through the northern Leeward Islands—not as a Category 2 as had been forecast, but as a powerful Category 3 storm, with sustained winds of 125 mph. Fortunately, Omar's increase in intensity was not matched by an increase in size. In its passage through the islands, hurricane force winds extended outward just 35 miles from the center. Fortunately, too, Omar threaded the needle through the Anegada Passage; its closest pass to land was about 25 miles to the east of St. Croix and about 55 miles to the northwest of St. Martin. However, many islands will have experienced tropical storm force winds, which extended some 115 miles from the center of the storm. Omar was also expected to bring high, battering waves to south-facing coasts from Puerto Rico to across the Lesser Antilles. Because of their considerable historical experience with tropical cyclones, building code enforcement and hurricane preparedness are generally good in most of the islands affected by Omar. In Puerto Rico, residential construction is often "bunker style" reinforced concrete with flat reinforced concrete roof slabs. However, in Culebra and Vieques—the islands to the east of the main island and closer to Omar's winds—more vulnerable wood frame single-family homes can be found. Commercial construction along coastal San Juan has a relatively high proportion of glass and other cladding materials vulnerable to wind loads. Following the hard lessons learned from Hurricane Marilyn in 1995, which damaged or destroyed 80% of homes and businesses on St. Thomas, most residential properties in the U.S. Virgin Islands are built of masonry or reinforced concrete. Roofing is normally galvanized steel, nailed or screwed on to wooden purlins. Commercial properties, such as hotels, are usually of reinforced or block concrete construction. In Dutch St. Maarten, common construction types for residential and commercial buildings are wood, masonry, and reinforced concrete. Newer construction is mostly concrete and most construction is low-rise. Commercial properties, such as hotels, are usually of reinforced or block concrete construction. In neighboring French St. Martin, low-rise residential buildings tend to feature wood or unreinforced masonry walls with wooden trussed roofing. Omar's gusty winds—particularly at higher elevations—are likely to cause damage to roof coverings and other non-structural elements, such as damage to glazing from windborne debris. Expected total rainfall of up to 10 inches—with a maximum of 20 inches in some pockets—brings the risk of flooding and landslides. In the U.S. Virgin Islands, Omar's approach shut down operations at the Hovensa oil refinery, the second largest in the western hemisphere with a capacity of about 500,000 barrels a day. However, very preliminary reports indicate that the islands have escaped any major structural damage, which is line with AIR's expectations. As of 8:00 AM EDT, Thursday, October 16, Hurricane Omar is located about 160 miles north-northeast of the northern Leeward Islands. Maximum sustained winds have decreased to near 115 mph and additional weakening is expected during the next 24 hours. Forward motion is to the northeast at 29 mph and a gradual increase in speed is expected. Omar is expected to continue on a northeast path into the open Atlantic and should have no further impact on properties onshore.

Landfall | Downloads
Posting Date: October 16, 2008, 8:00:00 AM