Hurricane Earl

Pre-Landfall 1 | Summary
Posting Date: August 30, 2010, 10:25:00 AM

The 2010 Atlantic hurricane season continues to show signs of increased activity. Though Hurricane Danielle weakened and passed well east of Bermuda over the weekend, Hurricane Earl—now a Category 3 storm—is battering the northernmost Leeward Islands with heavy rain, strong winds and tall waves, forcing vacationers to clear the beaches and prompting at least a dozen cruise ships to divert 20,000 passengers to other ports in the Caribbean and Mexico. Over the weekend, one Caribbean airline canceled 41 flights to several eastern Caribbean destinations in advance of Earl’s approach. As of the NHC's 1 PM EST advisory today, Earl is about 75 miles east northeast of the island of St. Thomas and 140 miles east northeast of San Juan, Puerto Rico. The storm is moving west northwest at 15 mph with maximum sustained winds of 125 miles per hour, up from 110 mph earlier this morning. The hurricane warnings that were in effect for the majority of the Leeward islands as of 8 am this morning are now only in effect for Anguilla, St. Martin, St. Barthelemy, St. Maarten, Saba, and St. Eustatius, as well as the British Virgin Islands and the U.S. Virgin Islands. In the Bahamas, the government has issued a tropical storm watch for the Turks and Caicos Islands, and a hurricane warning is now in effect for the Puerto Rican islands of Culebra and Vieques. In Puerto Rico, there is a hurricane watch. Thus far, the biggest impact from Earl in the northern Leeward Island region has been flooding; 10-foot coastal waves and heavy rain contributed to flooding in low-lying areas of Antigua, where strong winds also destroyed one house. In much of St. Maarten, electricity remains disrupted after wind toppled trees onto power lines. Storm surges of up to five feet are expected today within the hurricane warning area, and rain will continue to fall; parts of the Leeward Islands, the Virgin Islands and Puerto Rico could receive 4-8 inches, with isolated pockets receiving up to 12 inches of rain. This heavy precipitation could potentially cause flash floods and mudslides. The dominant construction type for homes in the northernmost Leeward Islands is masonry and a mix of masonry and reinforced concrete for commercial structures. A Category 3 hurricane is capable of producing minor to moderate damage to well-constructed residential buildings and minor to moderate damage to engineered structures. Poorly constructed homes and light metal structures such as warehouses could suffer significant damage. Non-structural elements such as signage and awnings are likely to sustain significant damage. Earl strengthened relatively quickly since its genesis. A tropical storm last Friday, it encountered a favorable environment of warm sea-surface temperatures and low wind shear over the weekend, reaching hurricane status on Sunday morning as it began its approach to the Leeward Islands. Earl reached Category 2 intensity late Sunday night. Between now and Wednesday, its intensity could increase to more than 130 mph—making Earl a Category 4 storm. Earl is presently tracking to the west northwest, which will position the center of the storm to the north of the Virgin Islands and Puerto Rico later today and tonight. Hurricane conditions will impact the northern Virgin Islands in the next few hours. Puerto Rico will experience tropical storm conditions this afternoon, and possibly hurricane conditions tonight. Between now and Wednesday, forecasts call for the track of Earl to gradually shift to the northwest; it should stay to the east of the Bahamas as it moves northward toward the U.S. The uncertainty in the track of the storm increases significantly beyond Wednesday. Earl may move along a course roughly parallel to the U.S. east coast. The current forecast takes the storm northward to a position due east of Cape Hatteras, North Carolina, before a frontal system from the Great Lakes turns Earl to the northeast, moving it farther from the coastline offshore of Cape Cod. Again, however, there is considerable uncertainty with regards to Earl’s track and it is too soon to assess any potential impact to the US East coast. Meanwhile, in the North Atlantic, Hurricane Danielle, a major Category 4 storm last week, has weakened significantly and is a very weak category 1 hurricane today. Its sustained winds are 75 mph. The AIR tropical cyclone team is closely monitoring developments and will provide updates as warranted by events. For information on current environmental conditions that may impact tropical storm activity (including sea-surface temperatures, wind shear conditions and steering currents), AIR offers a new service called ClimateCast®. Please visit the ALERT website for more information.

Pre-Landfall 1 | Downloads
Posting Date: August 30, 2010, 10:25:00 AM