Thursday, August 26, 2010

Hurricane Earl (2010)

Storm Active: August 25-September 4
On August 23, a strong tropical wave emerged off of Africa and immediately began to show signs of organization. The wave developed a low pressure center on August 24, and during that day, brought rain and gusty winds to the Cape Verde Islands. However, the system did not possess a closed circulation until August 25, and was then declared Tropical Depression Seven. Upon formation, Seven was already on the verge of tropical storm intensity and in another six hours, during the afternoon on August 25, the system became Tropical Storm Earl.

Overnight, the outflow of the system grew very organized, suggesting strengthening, but the location of the center itself was a moving target, reforming every few hours in a slightly different location relative to the convection. The center became more defined with a burst of convection during the evening of August 26, but the system did not undergo significant intensification overnight. Earl persisted westward during the day of August 27, and tropical storm watches were issued for portions of the northern Leeward islands as a result. Meanwhile, Earl began to strengthen, reaching strong tropical storm intensity by August 28. Despite an early turn north on the models, Earl continued west much longer than expected, and continued strengthening. Earl attained hurricane strength on August 29, and hurricane watches and warnings were issued for parts of the Northern Leeward Islands.

Finally, Earl turned westnorthwest later that day, but the outer bands of Earl began to sweep across the northeasternmost islands of the Caribbean bringing heavy rains and wind, with conditions getting progressively worse into the evening hours. By 8:00 pm EDT that night, tropical storm force surface winds covered the northern Leeward Islands, and hurricane force sustained winds also brushed these areas causing intense storm surge and flooding. Meanwhile, Earl continued to gain strength and rapidly became a Category 2 very late on August 29 and was on the verge of major hurricane strength by the morning of August 30. An eye appeared in Earl during the day as it strengthened rapidly, becoming a major hurricane quickly and then a Category 4 as it passed north of the U.S. Virgin Islands and Puerto Rico and caused tropical storm force winds and rain throughout the regions. Earl's pressure continued to drop, and by August 31, Earl had reached an amazing intensity of 135 mph winds and a 931 mb pressure. It still maintained a general westnorthwest motion, and the eye clouded over somewhat as Earl went through the Eye Replacement Cycle. The pressure rose as the cycle progressed, and Earl turned northwest, passing east of the Bahamas. But Earl maintained a Category 4 intensity until September 1, when it encountered some more significant shear and weakened to a Category 3 hurricane. Earl slowly turned to the north-northwest and recovered an eye, becoming more organized during the afternoon of September 1, and it restrengthened into a Category 4 hurricane. It surpassed its previous peak in intensity and reached its primary peak of 145 mph winds and a pressure of 928 mb early on September 2!

The storm continued to approach the Outer Banks of North Carolina during the day. By that evening, rainbands and tropical storm force winds swept over Cape Hattaras and the surrounding areas, as Earl turned north-northeast. However, hurricane force winds stayed offshore. As Earl approached, the eye clouded over again and Earl began steadily weakening, to a Category 3, and then a Category 2 by the time it passed by Cape Hattaras early on September 3. The weakening continued, and Earl was a tropical storm by the time it brushed passed Cape Cod overnight, bringing tropical storm force winds and rain to that area as well. By September 4, conditions were deteriorating in Nova Scotia. During the day, Earl made landfall in Nova Scotia and then Prince Edward Island as a powerful tropical storm, before entering the Gulf of St. Lawrence and finally becoming extratropical late on September 4 just off the coast of northeast Quebec. In total, Earl caused $150 million in damages and 3 fatalities over the areas it affected.

Earl nearing its peak intensity east of the Bahamas on September 1.

Track of Earl.

No comments: