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Tropical Storm Leslie hits Newfoundland; TD 14 forms

By: Dr. Jeff Masters, 2:55 PM GMT on September 11, 2012

Tropical Storm Leslie zoomed ashore over Newfoundland this morning near 8 am EDT, traveling with a forward speed of 40 mph. Leslie brought sustained winds to the capital of St. Johns of 58 mph, gusting to 82 mph, at 10:30 am local time. At least three other stations in Newfoundland recorded gusts over hurricane force: Cape Pine (85 mph), Bonavista (77 mph), and Argentia (74 mph). Damage to buildings has been reported in St. Johns, and the storm has knocked out power to much of Southeast Newfoundland, including the capital. Leslie's tropical moisture collided with the cold front drawing the storm to the north, resulting in heavy rains over Nova Scotia in excess of 4 inches, which caused considerable flooding of homes and streets. Overall, though, the damage to Canada appears to be far less than that of Hurricane Igor, which hit Newfoundland as a Category 1 hurricane in 2010, causing $200 million in damage. Leslie has now transitioned to a powerful extratropical storm, and will bring heavy rains to Iceland on Thursday, and to Scotland on Friday.


Figure 1. Tropical Storm Leslie as it crossed Newfoundland at 9:46 am EDT September 11, 2012. At the time, Leslie had top winds of 70 mph. The cloud pattern of Leslie looks more extratropical than tropical, and Leslie was no longer a tropical storm at this time. Tropical Storm Michael is visible at lower right, as a tight swirl of low clouds.

Hurricane Michael dying
The longest-lived hurricane of the 2012 Atlantic hurricane season was Michael, which attained hurricane status at 11 pm EDT September 5 and finally weakened to a tropical storm at 5 am EDT this morning. Satellite loops show that Michael has lost almost all of its heavy thunderstorms, and is racing to the northeast over colder waters. Michael will likely be declared dead later today.

Tropical Depression 14 forms
Tropical Depression Fourteen has formed midway between Africa and the Lesser Antilles Islands, from a tropical wave that emerged off the coast of Africa on Friday. The models unanimously predict that TD 14 recurve to the north well east of the Lesser Antilles Islands later this week, on a track that would likely keep this storm far out at sea away from any land areas. TD 14 is in a low-shear environment favorable for strengthening, and will likely become Tropical Storm Nadine by Wednesday.

Elsewhere in the Atlantic
The ECMWF model predicts that the cold front that swept off the U.S. East Coast Monday will leave a trough of low pressure over the ocean which could serve as the focus for development of a tropical or subtropical depression several hundred miles off the coast of North Carolina late this week.


Figure 2. Visible NOAA GOES-7 satellite image of Hurricane Iniki just before landfall in Hawaii at 8:01 pm EDT September 11, 1992. Iniki completed a “clean sweep” of National Weather Service offices responsible for issuing hurricane warnings. The National Hurricane Center in Coral Gables, Florida (Hurricane Andrew), the Joint Typhoon Warning Center in Guam (Typhoon Omar), and the Central Pacific Hurricane Center in Honolulu, Hawaii (Hurricane Iniki) were all struck by strong hurricanes within a 2-month span in 1992. Image credit: NOAA Environmental Visualization Lab.

20th anniversary of Hurricane Iniki
Twenty years ago today, Hurricane Iniki, the most powerful hurricane on record to strike the state of Hawaii, made landfall on the island of Kauai as a Category 4 storm with sustained winds of 145 mph and gusts up to 175 mph. Iniki brought storm tides of 4.5 - 6 feet (1.4 - 1.8 m) to Kauai, with high water marks of up to 18 feet (5.5 m) being measured due to large waves on top of the surge. Waves up to 35 feet (10.5 m) battered the southern coastline for several hours, causing a debris line of more than 800 feet (250 m) inland. The hurricane's high winds did incredible damage to structures on the island--5,152 homes were severely damaged, and some parts of the island were without power for three months. Iniki's $3 billion damage (2012 dollars) made the hurricane the second costliest Eastern Pacific hurricane, trailing Hurricane Paul, which made landfall in Mexico in 1982. Iniki holds the Eastern Pacific record for lowest pressure for a landfalling hurricane--945 mb (27.91").

Jeff Masters
"Leslie" surf@ Newport # 1

Hurricane

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