Weather forecast's critical new age

Warnings: The loss of life on a capsized harbor taxi raises questions about weather services' technology and reliability.

March 21, 2004|By Frank D. Roylance | Frank D. Roylance,SUN STAFF

EVERYONE agrees that the urgent marine warning from the National Weather Service came tragically late for those aboard the Lady D.

By 4:05 p.m. on March 6, when weather service forecasters urged boaters from Baltimore to the Patuxent River to "seek safe harbor immediately" from a squall line packing 50 mph gusts, 25 people from the Lady D were already swimming for their lives off Fort McHenry.

Five of them perished after the water taxi capsized, and their deaths generated hard questions about whether the forecasters in Sterling, Va., should have seen this danger coming and issued a more timely warning.

Sen. Paul S. Sarbanes, a Maryland Democrat, called for an outside investigation of the National Weather Service's performance. But internally, a "national service assessment review" was already under way.

Private weather service operators and some of their customers say they saw the storm coming with plenty of advance warning. It would be easy to conclude from all this that the government's forecasters have been eclipsed by nimble, for-profit weather service providers.

The far-flung instruments of the Web-based WeatherBug system recorded wind gusts in excess of 40 and 50 mph for an hour before the accident, as the storm front swept across the state toward the Inner Harbor.

A Doppler radar display on - based on a weather service feed - alerted the Inner Harbor's other water taxi service, which tied up all its boats before the squall hit.

AccuWeather claims it warned a Baltimore County client of 40-mph winds an hour before they struck.

"It seems to me this is today's technology," said Brian Hall, who credits WeatherBug for helping him protect his North Point marina from Isabel's storm surge last fall. The National Weather Service is "just such an antiquated, watered-down system."

But experts in and out of government say that such tales of success from commercial forecasters are anecdotal, and their true track record is unproven. The National Weather Service's record, they say, is good and improving. Furthermore, the agency remains the source of much of the new technology and weather data that the private sector repackages and sells at a profit.

"I don't think it's appropriate to be criticizing them," said Antonio Busalacchi, director of the Earth Systems Science Interdisciplinary Center at the University of Maryland, College Park. "The fact that this warning was issued contemporaneously with the event - that's something that could not have occurred 10 years ago," he said. "It's actually a sign of progress."

Initially, National Weather Service forecasters saw little to worry about in the line of squalls as it crossed the state that Saturday afternoon. "For most of the lifetime of that line of storms, even if the line was moving at 30 to 40 mph, you were not having those winds down on the surface," said Steven Zubrick, science and operations officer at the Sterling forecast office.

But WeatherBug instruments at dozens of public schools across Central Maryland were recording some surface gusts in excess of 40 and 50 mph. WeatherBug is an online service operated by AWS Convergence Technologies, a Gaithersburg firm that claims the largest network of weather stations in the world.

`We made the call'

As the front approached the harbor, employees in the Fells Point offices of Ed Kane's Water Taxis were watching a color-coded Doppler radar display on "We saw this red front coming right at us," said Cammie Kane, the fleet's owner. When skies darkened, "we made the call to shut them [the taxis] down and get the passengers off."

National Weather Service forecasters at Sterling were watching the same Doppler radar display, and just before 4 p.m., they issued a short-term forecast for thunderstorms and gusts to 45 mph as the front approached the city.

Installed by the government in the 1990s, the NEXRAD Doppler radar has vastly improved the accuracy and timeliness of government weather warnings - as well as the capabilities of commercial services such as Intellicast, which repackage it for their customers.

Sterling's own radar is just 45 miles from the Inner Harbor. But, because of the angle of its beam and the Earth's curvature, it can't see conditions below 4,000 feet here.

To track surface conditions, forecasters rely on ground stations. The National Weather Service has surprisingly few of its own - at Baltimore-Washington International Airport, Annapolis and Hagerstown. There's a station next to the Maryland Science Center at the Inner Harbor, too. But the building's proximity makes it impossible to measure wind there.

With limited surface data, tracking small storms like the March 6 squalls, and issuing timely warnings, pushes forecasters to the limits of their science and technology.

Filling in the gaps

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