Tuesday, August 19, 2008

Strong Start Increases NOAA’s Confidence for Above-Normal Atlantic Hurricane Season

Strong Start Increases NOAA’s Confidence for Above-Normal Atlantic Hurricane Season

August 7, 2008

High resolution (Credit: NOAA)

In the August update to the Atlantic hurricane season outlook, NOAA’s Climate Prediction Center has increased the likelihood of an above-normal hurricane season and has raised the total number of named storms and hurricanes that may form. Forecasters attribute this adjustment to atmospheric and oceanic conditions across the Atlantic Basin that favor storm development - combined with the strong early season activity.

NOAA now projects an 85 percent probability of an above-normal season – up from 65 percent in May. The updated outlook includes a 67 percent chance of 14 to 18 named storms, of which seven to 10 are expected to become hurricanes, including three to six major hurricanes of Category 3 strength or higher on the Saffir-Simpson Scale. These ranges encompass the entire season, which ends November 30, and include the five storms that have formed thus far.

In May, the outlook called for 12 to 16 named storms, including six to nine hurricanes and two to five major hurricanes. An average Atlantic hurricane season has 11 named storms, including six hurricanes and two major hurricanes.

Expected Conditions During 2008 Atlantic Hurricane Season.

High resolution (Credit: NOAA)

“Leading indicators for an above-normal season during 2008 include the continuing multi-decadal signal – atmospheric and oceanic conditions that have spawned increased hurricane activity since 1995 – and the lingering effects of La NiƱa,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center. “Some of these conditions include reduced wind shear, weaker trade winds, an active West African monsoon system, the winds coming off of Africa and warmer-than-average water in the Atlantic Ocean.”

Another indicator favoring an above-normal hurricane season is a very active July, the third most active since 1886. Even so, there is still a 10 percent chance of a near normal season and a five percent chance of a below normal season.

Hurricane Dolly on July 23, 2008.

Hurricane Dolly on July 23, 2008.

High resolution (Credit: NOAA)

NOAA’s hurricane outlook is a general guide to the expected level of hurricane activity for the entire season. NOAA does not make seasonal landfall predictions since hurricane landfalls are largely determined by the weather patterns in place as a hurricane approaches.

Five named storms have formed already this season. Tropical Storm Arthur affected the Yucatan Peninsula in late May and early June. Bertha was a major hurricane and the longest-lived July storm (July 3-20) on record. Tropical Storm Cristobal skirted the North Carolina coastline. Dolly made landfall as a Category 2 hurricane at South Padre Island, Texas on July 23. And on August 5, Tropical Storm Edouard struck the upper Texas coast.

Water vapor animation.

Atlantic water vapor animation.

Download as Quicktime [MP4] (Credit: NOAA)

“It is critical that everyone know the risk for your area, and have a plan to protect yourself, your family and your property, or to evacuate if requested by local emergency managers. Be prepared throughout the remainder of the hurricane season,” Bell said. “Even people who live inland should be prepared for severe weather and flooding from a tropical storm or a hurricane.”

The Atlantic hurricane season includes activity over the Atlantic Ocean, Caribbean Sea and Gulf of Mexico. The peak months of the season are August through October.

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.




National Hurricane Center Podcast (Experimental)

Tue, 19 Aug 2008 12:28:54 GMT
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NHC Audio Briefing Created Tue, 19 Aug 2008 12:28:54 GMT
Tue, Aug 19, 2008 7:28 AM

Experts boost forecasts for rest of hurricane season
by Mark Schleifstein, The Times-Picayune

Saturday August 16, 2008, 9:24 PM

There's hotter-than-normal water on the surface of the Atlantic Ocean between Africa and the Gulf of Mexico. The water's still a bit cooler than normal off the Pacific coast of South America.

Upper-level winds over the Atlantic are mostly blowing from the east. And lingering low-pressure systems at the water's surface in the tropical Atlantic are more frequent and with lower pressure than normal.

Add them together, and these conditions represent the perfect ingredients for a more-active-than-normal end to the hurricane season, say experts at both the National Weather Service and Colorado State University's Tropical Meteorology Project.

Hurricanes gain intensity and size from warmer water in the Atlantic, while the cooler La Nina water conditions in the Pacific reinforce wind conditions that help spin the thunderstorms fed by the low-pressure systems into hurricanes.

Colorado State meteorologists Phil Klotzbach and Bill Gray last week updated their preseason hurricane activity estimate on the basis of those conditions, predicting 17 named storms, with nine becoming hurricanes and five becoming major hurricanes, Category 3 or higher.

The National Oceanic and Atmospheric Administration Climate Prediction Center updated its estimates last week on the basis of the same conclusions: 14 to 18 named storms, with seven to 10 becoming hurricanes, and three to six being major hurricanes.

Both cited this year's fast start -- the third-most-active July since 1886 -- as an indicator of what's to come.

There already have been six named storms, including Category 3 Hurricane Bertha -- the longest-lived July storm on record, at 17 days -- and Category 2 Dolly, which caused $1.5 billion in damage when it went ashore on the Mexico-Texas border.

But even though mid-August begins the period when the chance of hurricanes in the Atlantic and Gulf ramps up dramatically, "don't worry too much about these seasonal forecasts," said Steve Lyons, the Weather Channel's resident tropical weather expert.

"The only thing that really matters is how many hit the United States coastline and where, and nobody knows that so far in advance of actual landfall," Lyons said Thursday during a telephone interview.

Always uncertainty

An example is Hurricane Alicia in 1983, Lyons said, which hit Houston as a Category 3 storm in a relatively inactive season.

"That hurricane season had a total of only four named storms, but three hit the U.S., and one was a major hurricane in a major city," he said. "Other years are very active, and hardly any have hit the coastline."

People should focus instead on preparing themselves, he said, both being ready to move to safety in advance of a hurricane, and preparing their homes for hurricane damage.

"We're not ever going to be able to stop a hurricane," Lyons said. "Even if you know five days in advance that a storm will hit New Orleans, you may save lives -- assuming that people follow directions of emergency managers -- but you're still not going to be able to save their property."

Lyons noted that the Bush administration decided last week to ask Congress for more money to improve forecasting. But he said the federal government also should focus on preparing the nation's coastlines for the effects of hurricanes before they hit, whether it be adoption and enforcement of more stringent building codes in Florida and East Coast cities, or on levees and wetlands in areas like Louisiana.

"Nothing's going to stop the devastation of coastal communities until the fixes are made there, and that will take time and money, and it takes government to force people to do it," Lyons said.

"And that's the question that people should be asking the candidates (for president), in my opinion," he said. "What are you doing to fix it?"

The reason for Lyons' concern becomes clear during a Weather Channel special that premieres Monday at 8 p.m.

Imagining worst what-ifs

In "Storm Session: Hurricanes 2008," hosted by storm tracker Jim Cantore, Lyons and other Weather Channel forecasters outline their worst-case hurricane possibilities for the United States.

Lyons calls them "Armageddon tracks."

"I took a Category 4-5 hurricane angling across Miami and Fort Lauderdale and then taking a left hook, slowing and going over Tampa," he said. His storm then restrengthens into a Category 4 or 5 hurricane as it moves slowly west over the northern Gulf of Mexico, flooding parts of New Orleans and then slamming into Galveston, Texas, and Houston.

Such a storm would create multiple catastrophes, Lyons said. In Florida, the multibillion-dollar damage would bankrupt the insurance industry, requiring a massive bailout by the federal government that would dwarf the cost of Hurricane Katrina.

But the storm's path over the Gulf would be equally devastating, trashing offshore oil and gas production for months and then devastating onshore refineries in a Houston landfall that would leave that city in shambles too.

"It's a storm that would affect every state in the union if it happened," Lyons said.


U.S. Coast Guard Air Station Traverse City records busiest week of summers rescue season

Thursday, 14 August 2008

In a five-day period the Coast Guardsmen have logged more than 50 flight hours on 12 search and rescue cases resulting in four lives saved.

On Friday a single helicopter crew rescued three people in two separate cases: rescuing two overdue fishermen who were clinging to their capsized vessel near Alpena, Mich., and finding a missing kayaker in Torch Lake, Mich. On Wednesday helicopter crews airlifted and medically evacuated a 42-year-old male from the Burns Harbor, a 1,000-foot laker. The vessel was 60 miles east of Marquette, Mich., in Lake Superior.

During this period, the air station nearly doubled their weekly average flight time.

"In a typical five-day period, we would fly approximately 30 hours of training missions and routine patrols," said Capt. Stuart Merrill, commanding officer of Air Station Traverse City. "This week we almost doubled that time and it was solely dedicated to the search and rescue mission."

This five-day period to the helicopter crews from Marquette, Mich., to Sheboygan, Wisc., and as far south as Chicago and several other locations in between.

"I am tremendously proud of the dedicated efforts of our aviation crews," said Merrill. "During the past week, they have committed unbelievable time and energy protecting the safety of the mariners and beachgoers throughout the Great Lakes region."

"Our ethos of 'Safe Search and Rescue Response Readiness' is embodied in their actions each and every day and particularly during this demanding past week," he added.

Air Station Traverse City operates five HH-65C Dolphin helicopters and assists with search and rescue services throughout the Great Lakes Region encompassing more than 94,000 square miles of water and 10,900 miles of shoreline. Their area of responsibility encompasses five states, three Great Lakes, and assistance to Canada when requested.