RIVERTON - On any given day, they hope to be pressed into duty.

Their mission? To help Fremont County and the state of Wyoming pull out of an extreme drought.

The husband-and-wife team of Jody and Erin Fischer, as well as Jason Goehring and Brook Herridge, make up a foursome from Weather Modification Inc., based in Fargo, N.D. They have been stationed in Riverton since early January and are contracted to stay through the end of March.

Using a Piper Cheyenne 2 airplane complete with flares and probes on the wings, pilot Jody Fischer and co-pilot Herridge, fly over the Wind River Mountains and run cloud-seeding missions with hopes of producing additional snowfall, which would increase the winter snowpack and improve the runoff in the spring.

At the appropriate time, the flares are lit and they release chemicals into the clouds, hoping to produce a reaction that will create snow.

Erin Fischer is the data systems operator in the plane. She sits in the back and stares into a computer screen as the machine collects data through the probe on the wing.

On the ground, Goehring is the project meteorologist. It's his responsibility to determine when the weather conditions are right.

"We're in year two of a five-year pilot program," Goehring said. "We're funded by the Wyoming Water Development Commission, and our job is to increase the amount of snow that falls out of the clouds and onto the mountains."

Fremont County and much of Wyoming are in the midst of a long and extreme drought. The state is looking for anything to help end the dry conditions.

The Wind River Basin is among the areas that have been hit hardest. Riverton received only 53 percent of average precipitation in 2006, according to the National Weather Service.

During the past six calendar years, Riverton has received normal precipitation twice and twice has fallen well below the norm. Last year, 4.64 inches of precipitation was recorded downtown, compared to the 30-year normal of 8.68. In 2001, the first year of the drought, 5.07 inches was recorded. In 2003 and '04, Riverton received above-normal amounts of 10.03 and 9.84 inches, respectively.

The Wyoming office of the Bureau of Reclamation predicts the spring snowmelt runoff will be below average for all areas of the Bighorn River Basin. The latest forecast was made Feb. 1.

According to Wyoming area manager John Lawson, the Wind River portion of the Bighorn River Basin April through July inflow forecast, which includes the snowmelt runoff into Bull Lake Reservoir from Bull Lake Creek northwest of Riverton, is expected to be about 83 percent of average.

The snowmelt runoff into the Wind River above Bull Lake Creek is expected to be 75 percent of average. The expected inflows to Boysen Reservoir are predicted to be 63 percent of average.

"The early predictions don't look good," Lawson said. "With less snowpack, runoff also would be less.

"At this point, it doesn't look like we're going to get full recovery. But, we could still be OK if we get some heavy, wet, late snows.

"But regardless of what happens, we still should have an adequate water supply this year."

Jody Fischer said the goal of the cloud-seeding program is to increase the amount of snowpack about 10 to 20 percent.

"That may not sound like a lot, but more snow falling over the mountains means more snowpack," he said. "When that increased snowpack melts, it increases the streamflows and helps fill the reservoirs.

"This is a long-term tool to help manage water."

The Wyoming Water Development Commission is overseeing the conduct of the state's weather modification pilot program.

Besides using the airplane, ground-based launches also can be used.

Ground-based and airborne cloud-seeding efforts use a silver iodide-based seeding agent contained in the flares.

The program is scheduled to continue over five successive winter seasons.

The seeding does not take place during intense storms that potentially already can produce heavy snows.

Under average conditions, seeding may be feasible six to 10 times per month, depending on conditions.

"The weather has to be just right," Goehring said. "I'm actually on call 24-7 until the end of the project on March 31."

Goehring determines when the time is right for the pilots and Erin Fischer to take flight by checking weather patterns and conditions. When he gives the green light, the trio - sometimes with an analyst, scientist or technician joining them - takes off from Riverton Regional Airport and heads toward the clouds over the Wind River Mountains.

"When he tells us to go, we hop in the plane and take off for the clouds," Jody Fischer said.

"We're looking for super-cooled water, which is water already existing at below-freezing temperatures in the clouds. When we find the right conditions, we light the flares as we fly and drag them across the clouds. The process converts the water into snow and it falls.

"One way to say it is that we're getting the natural process going better and faster."

Because the conditions must be just right, the team had not taken flight as of Feb. 9.

"But it could and should be any day," Goehring said.

"I'm very confident we'll get some good flying days and we'll get the job done," he said. "We'll get them up as often as the weather permits."

"The clouds have been right recently, but it's been too warm," said Bruce Boe, director of meteorology at Weather Modifications. "But it looks like colder temperatures are on the way. It looks like we're going to get into favorable conditions. I'm optimistic we will get opportunities very soon."

On the ground, five generators basically attempt to do the same thing.

"They are deployed by the south end of the Wind Rivers," Boe said. "They burn a solution that produces an ice-forming nucleus and then rely on the air flow over the mountains to spread and seed."

When the plane is airborne, Erin Fischer sits behind the pilots and monitors the action in the clouds by watching a complicated-looking computer program that collects the data through the probe on the left wing.

She is not analyzing the data, but watching it and making sure all is going as it is supposed to.

"I look to make sure all the instruments are taking in the data," she said. "I verify everything is working. I archive the data and then send it to an analyst team.

"I'm the first check. I make sure all is well."

The collected data is sent to NCAR, or the National Center for Atmospheric Research in Boulder, Colo., where it is checked and evaluated.

"They help us build a complete picture of what's happening," Boe said. "They analyze the data and compare it to data previously collected. They make sure everything is going how it is supposed to."

Jody Fischer, 31, earned an aviation degree at the University of North Dakota and served an internship at Weather Modification. That got him interested in the cloud-seeding program.

"I could be flying commercial jets," he said. "But I thought this would be a very cool job, and it is."

Erin, 24, met Jody in Fargo. She was attending the University of Minnesota at Moorehead at the time.

"The program looked interesting, so I got into the research end of it," Erin said. "I traveled to India with Jody on a project and actually learned how to do my job on the spot. It's great to be a part of something like this."

Jody and Erin have been married for four years. Jody has been with Weather Modification for seven years while Erin has been there for about six.

Herridge, 29, has been at WMI for three years, while Goehring, 27, has been a company meteorologist for two years.

"This crew here in Riverton is a dedicated group," Boe said. "They are a superb crew the best we have in Wyoming."

"It's awesome to be directly involved with the weather," Goehring said. "I'm not just forecasting. I'm actually doing something that makes a difference."

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