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New radar installation delayed for second time

Local National Weather Service officials aren't worried, even though the installation of the next generation of radar has been delayed for the second time — pushing the debut ever closer to tornado season.

Wichita is the first weather service branch to receive the National Oceanic and Atmospheric Administration's dual polarization radar, which shoots two beams out to collect information: one horizontally and another at about 45 degrees.

From that data, forecasters will be better able to detect how heavily it's raining in various parts of a storm, how large hail in the storm is — even where in a winter storm the precipitation is rain, ice or snow.

The new radar will be able to differentiate between storms and "ground clutter" such as buildings, and can even detect tornadoes on the ground.

Current Doppler radar, which debuted in 1988, can detect rotation in the clouds, but can't "see" a tornado on the ground. The new radar can, by detecting debris a tornado picks up as it moves along.

That's important, forecasters say, particularly if the twister has touched down at night, or at other times and places when spotters or law enforcement officers are not in position to see it.

The new radar won't eliminate the need for spotters or eyewitnesses because they provide "ground truth" confirmation on whether a tornado has touched down and what it is doing at the moment, said Chance Hayes, warning coordination meteorologist for the Wichita branch.

Wichita was chosen as a test site for the new radar, officials said, because this area experiences a wide range of weather and it's close to the radar's home base of Norman, Okla., so technicians won't have far to travel if problems arise.

"There's always a learning curve," said Mike Smith, president and CEO of WeatherData, a Wichita-based subsidiary of AccuWeather. "You don't know what you don't know."

About a half-dozen dual polarization radars are already in use by television stations and private forecasting companies around the country.

WeatherData has had "limited experience" with the new radar in Oklahoma, Smith said.

"The dual polarization radar produces more accurate estimates of rainfall," he said. "We'll be able to do a better job of hail-size warnings, and we'll be able to do maybe a better job of distinguishing whether there's a tornado on the ground or not."

Hayes said local meteorologists expect the new radar to better monitor thunderstorms and winter storms.

The radar "shows us in the storm where the rain is, where the ice is, where the snow is," he said.

"You can see that within the storm. We should have a better grasp on how to better differentiate those."

The radar will also provide images showing how hard it's raining at any given moment. Current radar offers only estimates of how much it will rain in an hour over a given point.

"That rainfall intensity component is important because it's going to help us with flooding forecasts," Hayes said.

The radar is sensitive enough to be able to tell forecasters how large the raindrops are in a thunderstorm. The bigger the drops, the more moisture that accumulates in a shorter period.

"That's going to help us out quite a bit, too," Hayes said.

The new radar was supposed to be installed in October, then early January. Now the installation has been pushed back again, and local officials haven't been given a new installation date yet.

But they're not concerned.

"The staff is training online," Hayes said. "We'll be fine."

The Wichita branch will not have a functioning radar for about 10 days when the new radar is finally installed, Hayes said.

But radars in surrounding weather service branches such as Topeka, Dodge City and Vance Air Force Base in Oklahoma overlap the Wichita area and can provide interim radar coverage.

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