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Meteorologist Sven Nelaimischkies points out an antenna used to track weather balloons at Medford's National Weather Service office. - Jamie Lusch

Strike Force

When lightning strikes, the men and women of the National Weather Service strike back. Sort of.

Their mission at the Medford office of the National Oceanographic and Atmospheric Administration's NWS office is to provide data about incoming weather systems and atmospheric conditions and disseminate it to local customers.

Its location in the 4000 block of Cirrus Drive near the Medford airport is identifiable by its large, bulbous antenna array and what appear to be several other satellite dishes and pieces of monitoring equipment on the roof of what otherwise could be any commercial office building.

As of Thursday afternoon, the equipment had tracked more than 1,200 individual lightning strikes in Southwestern Oregon and Northern California for the previous day. Additionally, it was able track the potential ignition sites for forest fires caused by those strikes, using satellite imagery of the area.

It then relayed this data to agencies including the Oregon Department of Forestry, Bureau of Land Management and the U.S. Forest Service.

Predicting lightning storms is one thing, but how does the weather service go about tracking each individual strike?

When lightning strikes the ground it discharges energy, and an electromagnetic pulse is created, said NWS meteorologist Sven Nelaimischkies.

A network of specialized sensors is set up throughout the country and tuned to the electronic frequency of lightning strikes.

When a sensor picks up a signal, other sensors triangulate to determine the strike's location. The system is computerized and automated and allows the NWS to monitor a large number of strikes with precision.

Additionally, the NWS constantly monitors weather conditions that could lead to a thunderstorm, using integrated resources including weather balloons and radar.

Weather balloons are launched across the globe in sequence with Greenwich Mean Time. On the ground they're about four feet in diameter, but can expand to the size of a house once the hydrogen that fuels them expands at higher altitudes.

The balloons carry monitoring equipment that monitors wind speed, air pressure, humidity and other measurements. The data are collected and beamed back to a radio antenna at the Medford facility. The antenna is housed in the giant dome structure that stands atop the building.

Once this data is processed, it's disseminated to a variety of the Weather Service's customers, said meteorologist Mike Stavish.

Those include aviation, fire prevention and monitoring, the U.S. Forest Service and marine and boating interests. Stavish said the NWS tries to offer customized and specific services to customers depending on what they're looking for.

"We try to engage in a relationship with our customers to create better products to suit their special needs and decisions," he said.

As he monitored a potential thunderstorm developing Thursday afternoon, meteorologist Mike Petrucelli said his focus this time of the year is on fires and lightning, but will shift to monitoring severe winter weather in the coming months. He said he prefers the winter weather.

"I grew up on the East Coast and I was used to that kind of colder weather and more snow," Petrucelli said.

The inside of the NWS office is filled with charts, maps and computer banks with screens showing overhead shots of the nation and region. The computers display images relating to cloud buildup, atmospheric pressure and, on a national level, Hurricane Irene barreling toward the East Coast. They also display the information collected by the lightning sensors and weather balloons, along with overhead satellite imagery.

The NWS seems to have every angle covered, but its equipment isn't foolproof.

Fear not. In the event technology fails, the Weather Service has a backup plan, although it's decidedly low-tech.

Resting between the workstations of Petrucelli and Stavish sits an angry, glaring plastic wizard encased in a crystal ball.

"Will we have lightning tonight?" Stavish asks, waving his hand over the blue and purple robed figurine.

The wizard's motion-sensor red eyes light up and it imparts its mystical knowledge.

"Consult someone of the opposite sex," it says in an electronic rasp.

"Well, there you go, that's what we have to do," Stavish said. "That's how we do it."

Mat Wolf is a reporting intern from the University of Oregon. Reach him at 541-776-4481 or by email at mwolf@mailtribune.com.

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