NOAA METEOROLOGISTS RECALL DRAMA OF FORECASTING "THE PERFECT STORM"
June 29, 2000 Some of the NOAA meteorologists, who forecasted
the "Perfect Storm" in October 1991, recalled the unprecedented
weather events that created the storm, the dramatic effort to
predict it and the improvements in forecasting that followed
it. (NOAA satellite image of "The Perfect Storm,"
October 30, 1991.) [Click image for larger view.]
The stormcreated from a collision between a high pressure system, a low pressure system and the remnants from a dying hurricanesent high winds and Atlantic Ocean waves crashing into the East Coast, from New England to Cape Hatteras, North Carolina.
"Nine years ago, this event presented a unique challenge to our forecasters," Baker said. "Today, our better understanding of the weather and our improved forecast technology give us greater abilities to predict storms of this variety."
Unlike 1991, Uccellini said today's marine forecasts extend as far out as 96 hours, providing ship crews critical advance time of any possible storm activity."Though our forecasts were quite good for this storm in 1991," Uccellini said, "we can do even better today."
He said the National Weather Service's 10-year $4.5 billion modernization program, which was completed in 1999, brought significant enhancements, including Doppler radar, the Advanced Weather Interactive Processing System, a new supercomputer and new satellite technology.
"NOAA satellites play a key role in marine forecasting because they help detect the first stages of storm development," Uccellini said, adding that 85 percent of the data used by forecasters comes from satellites.
Case, who is now retired, is credited with coining the term "perfect storm." He said he warned the public, while working at the Boston forecast office, that the storm would take on epic proportions. "It was an unprecedented set of circumstances," the now-retired weatherman said. "A strong disturbance associated with a cold front moved along the U.S.-Canadian border on October 27 and passed through New England pretty much without incident. At the same time, a huge high pressure system was forecast to build over southeast Canada.
"When a low pressure system along the front moved into the Maritimes southeast of Nova Scotia," Case reflected, "it began to intensify due to the cold dry air introduced from the north." Case added: "These circumstances alone, could have created a strong storm, but then, like throwing gasoline on a fire, a dying hurricane Grace delivered immeasurable tropical energy to create the perfect storm."
Sienkiewicz, of NOAA's Marine Prediction Center in Camp Springs, Md., remembered feeling a growing concern at what he saw from the computer models.
"Even though we were predicting what was going to happen, we just knew there were some boats that wouldn't be able to get out of the way of this monster," said Sienkiewicz, who is also a wave expert. He said during the Halloween Nor'easter, "rogue waves," which towered as high as 100 feet, made matters worse for mariners stuck at sea.
"If you're facing average
wave heights of 50 feet, it is possible that you'll see a wave
as tall as 100 feet, or higher," Sienkiewicz said. "Rogue
waves can result if waves meet from different directions, or
if they interact with currents, such as the Gulf Stream...Either
way, they are devastating."
To ensure that the nation's fishing vessels are equipped for an emergency, NOAA reminds vessel owners and operators that emergency position-indicating radio beacons, or EPIRBs, are mandatory equipment on most commercial fishing vessels, and the EPIRBs must be registered with NOAA.
NOAA reminds vessel owners to follow the manufacturer's instructions for properly mounting, testing and using the EPIRB.
NOAA is the lead U.S. government agency for the international search and rescue system that uses satellites to detect and locate emergency beacons. The system consists of a network of satellites, ground stations, mission control centers, and rescue coordination centers. When an emergency beacon is activated, the signal is received by a satellite and relayed to the nearest available ground station. To date, more than 10,000 lives have been saved with this system.