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Igor delivers punishing blow to Newfoundland; 95L growing more organized

By: Dr. Jeff Masters, 1:21 PM GMT on September 22, 2010

Hurricane Igor delivered a punishing blow to Newfoundland Canada, which suffered one of its worst poundings by a hurricane in the past century. Igor made it all the way to southeast Newfoundland yesterday as a Category 1 hurricane, bringing a peak wind gust of 107 mph to Cape Pine in Southeast Newfoundland. Igor brought sustained winds of 58 mph, gusting to 85 mph, to Newfoundland's capital, St John's. The city recorded a remarkably low pressure of 958 mb, and picked up 3.99" of rain during Igor's passage. Widespread rain amounts of 5 - 9 inches fell over much of southeast Newfoundland's rocky terrain, which is unable to absorb so much water. The resulting severe flooding washed out hundreds of roads, collapsed several major bridges, and forced numerous rescues of people trapped on the second stories of their homes by flood waters. Igor generated swells of 6 - 8 meters (20 - 26 feet) that pounded the southern coast of Newfoundland last night and this morning; significant wave heights reached 39 feet at the Newfoundland Grand Banks Buoy, and a storm surge of a meters (3.28 feet) hit the northeast shores of Newfoundland last night. Igor is now a large and powerful extratropical storm off Greenland and Labrador, and continues to generate hurricane force winds over water--winds at Angisoq, Greenland were sustained at 66 mph this morning.

It is not that unusual for hurricanes to penetrate as far north as Newfoundland's latitude; over 40 hurricanes have done so. The last time this occurred was in 2003, when Hurricane Fabian made it to latitude 48.7°N as a hurricane. The all time record is held by Hurricane Faith of 1966, which followed the Gulf Stream and maintained hurricane status all the way north to latitude 61.1°N, just off the coast of Norway.


Figure 1. Little Barsway bridge 10 km north of Grand Bank, Newfoundland, after floodwaters from Hurricane Igor swept it away. Image credit: George J.B. Rose.


Figure 2. Hurricane Igor at 11:47am EDT on Wednesday, September 21, as it pounded Newfoundland as a Category 1 hurricane with 75 mph winds. Image credit: Environment Canada.


Figure 3. Video of impressive flooding on Newfoundland's Burin Peninsula, whose 20,000 residents were cut off from the rest of the province by flooded roads and closed bridges.

Dangerous Caribbean disturbance 95L growing more organized
A tropical wave (Invest 95L) moving westward at 15 mph though the south-central Caribbean is bringing gusty winds and heavy rain to the northern coast of Venezuela and the islands of Curacao, Aruba, and Bonaire this morning. A wind gust of 38 mph was recorded at Curacao last night. Radar from Curacao and satellite loops show that 95L's thunderstorms have a pronounced rotation, with a center of circulation located just off the coast of South America. Thunderstorm activity is fairly limited, but is slowly increasing in areal coverage and intensity. Wind shear over the Caribbean is low, 5 - 10 knots, and is forecast to remain low to moderate, 5 - 15 knots, for the rest of the week. NHC is giving the disturbance a 60% chance of developing into a tropical depression by Thursday. I'd put the odds higher, at 70%. The Hurricane Hunters are scheduled to investigate 95L this afternoon.

The wave should continue moving westward near 15 mph through Friday afternoon, when it will arrive near the northern coast of Nicaragua. Most of the models show some development of 95L by Thursday or Friday, and the disturbance will bring heavy rains to the Netherlands Antilles Islands and north coast of South America on today and Thursday as passes to the north. Heavy rains may also spread to Southwest Haiti and Jamaica on Thursday, and the Cayman Islands, Cuba, Honduras, and Nicaragua on Friday. When 95L moves over or just north of Honduras on Saturday, a trough of low pressure diving southwards over the Eastern U.S. will weaken the steering currents over the Western Caribbean and cause 95L to turn more to the northwest and slow. If the center of 95L remains over water, the storm could easily develop into powerful and dangerous Hurricane Matthew over the Western Caribbean early next week. Even if the center stays over land, the circulation of the storm may be capable of generating dangerous flooding rains over Central America. Steering currents will be weak over the Western Caribbean through the middle of next week, and 95L may spend up to a week over the Western Caribbean, drenching the region with very heavy rains. Another possibility is that the trough of low pressure over the Eastern U.S. will be strong enough to draw 95L northwards across western Cuba and into the Gulf of Mexico 6 - 8 days from now. This solution is not being emphasized as much in today's model's runs as yesterday's, and the danger to the U.S. is uncertain at this point.


Figure 4. Morning satellite image of 95L.

Tropical Storm Lisa
Tropical Storm Lisa continues to churn the waters of the far Eastern Atlantic. By Friday night, upper level winds out of the west are expected to increase, bringing high wind shear of 20 - 45 knots over Lisa. The high shear may be capable of destroying the storm by early next week. It appears unlikely that Lisa will affect any land areas.

Georgette headed towards Arizona
Tropical Depression Georgette hit the tip of Baja California as a weak tropical storm with 40 mph winds yesterday, but dropped little rain. Georgette is in the Gulf of California, headed northwards, and could bring heavy rains to Arizona on Thursday.

Hurricane Karl's aftermath
Mexico continues to clean up from Hurricane Karl, which made landfall last Friday in Veracruz state as a Category 3 hurricane with 115 mph winds. Karl dumped approximately one foot of rain in the Sierra Madre Oriental Mountains, which cause some rivers to rise to unprecedented levels. The death toll from Karl's flooding and mudslides stands at 16, and ten of thousands remain in shelters after being displaced from their flooded homes. Insurance company AIR Worldwide is estimating insured losses at $100 - $200 million. Actual damage is estimated to be as much as $3.9 billion, since insurance take-up rates are low in Mexico. Karl is the second billion-dollar hurricane to hit Mexico this year; in June, Hurricane Alex hit just south of the Texas border as a Category 2 storm, killing 51 and doing $1.9 billion in damage.

Elsewhere in the tropics
The GFS model predicts a new tropical depression might develop in the Central Caribbean about seven days from now. The NOGAPS model predicts a new tropical depression will form off the coast of Africa about seven days from now.

My next post will be Thursday morning.

Jeff Masters
Uprooted Buoy
Uprooted Buoy
A buoy is left stranded on the beach from the storm waves of Hurricane Igor...

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.