Inside bad weather

New mobile radar truck holds key to improved forecasting
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Even with dozens of TV-station meteorologists and national and regional weather services following the development of storms like the recently passed Isidore and Lili, the reality is that, for all the science involved, tracking tropical storms and hurricanes is still inexact.

By the 2003 hurricane season, though, forecasters hungry for information will have a new source: a mobile radar vehicle built by Florida State University. It has already been involved in tracking some of this season's storms and even made an on-air appearance for The Weather Channel during Tropical Storm Isidore. By next year, it will be further improved, and the Weather Channel intends to figure out how to easily get the radar information to viewers.

"We can be at the best place for the best data, which can be combined in real time or later with other kinds of data," says Dr. Peter Ray, who drives the truck and is a professor at Florida State University's department of meteorology. "From that, we can get information that would otherwise be impossible to get."

For example, Ray notes, Doppler radar measures only the speed of wind blowing to and from the radar. But the radar truck can gather information that, in tandem with data from another Doppler site, could depict three-dimensional flow structures like updrafts and downdrafts, which could be used to determine where tornadoes might occur. It also can measure maximum wind speed every hundredth of a second as opposed to an average speed.

The flatbed truck weighs 35,000 pounds and has a large cab that contains all the operational equipment: transmitter, receiver, display and controls. On the flatbed is a 25,000-W generator and a horizontal radar antenna that lifts to the vertical and can extend 30 feet. According to Ray, two pairs of outriggers extend more than 25 feet out from the truck, helping it withstand hurricanes of Category Five strength.

Terry Connelly, Weather Channel SVP, programming and production, says the truck is very powerful, precise and accurate. "It's so new," he adds, "that, when we used it for Isidore, we couldn't connect to it, but we did use a camera to get shots of the monitor showing the radar in the truck."

The advantage the truck offers, he says, is that the closer you get to a storm, the more accurate the measurements.

Doppler radar, like that used in the truck, plays a big role at all weather-forecasting services and stations. WGNO(TV) New Orleans used Doppler radar technology to track the eye of Hurricane Lili as it moved inland within the New Orleans market. Says chief meteorologist Bruce Katz, "We had several tornadoes and warnings, which the radar can depict. When a storm is coming in, it's the Super Bowl for the weather guy, where we can show off all of our tools and what we have."

The radar technology available in the FSU truck is particularly important because a hurricane is more than just wind and rain. "If we can get accurate simulations of what we're observing, then we can look at ways of even weakening the hurricane some while it's out at sea," says Ray. "Attempts in the past haven't been successful, but there may be other strategies and techniques that could reduce the amount of rainfall or wind speed. And if you reduce the wind speed even a few miles an hour, you can save buildings."

Getting the information to The Weather Channel directly will be the next challenge. There are ways to get the data out of the truck and to The Weather Channel, Ray says, but they require some setup. "That's impossible to do during a hurricane because everyone is busy. But there are a number of technologies that work, and which one to deploy is a matter of cost and effectiveness."

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