GRAY — Meteorologist Jim Hayes has been tracking the same storm over the past few days, watching as it winds its way east.

He’s been on shift at the National Weather Service office in Gray since Tuesday night and now, just after 4:30 a.m. Wednesday, he’s waiting for the the storm to cross over into Maine.

The phone rings — the first of many calls from Maine school superintendents he’ll take for the next hour or so. The school won’t have trouble getting kids to school, he says, but getting them home will be a different story.

“It won’t be bad to start, but it gets bad later on,” he tells the Portland schools’ boss. “You should probably see 6 inches before noon, and it could switch over to rain tonight.”

He hangs up. “Looks like we just closed Portland schools,” he says.

That’s how the next few hours go at the National Weather Service office in Gray. Hayes and John Jensenius will take plenty of phone calls from school superintendents, public works directors and police departments checking the status of Wednesday’s winter storm.

At the same time, they monitor banks of computer screens displaying whirling radar models, beeping weather forecasts and condition reports from around New England.

Jim Brown, the office’s hydro-meteorological technician, arrives at about 5 a.m. to launch a weather balloon. They’ll track that, too.

Then they’ll take more calls from volunteers and amateur weather spotters reporting conditions from around the state.

All of the information they gather will be sent off to a weather service clearinghouse in Washington, D.C., and returned to them in the form of more computer models and a precise picture of Maine’s first severe weather storm for the 2009-10 winter.

“I love this job, especially on storm days, matching wits with the atmosphere,” Hayes said. “On the good days, you do really well and on the bad days, maybe not so well. But I still love it.”

Hayes, Jensenius and Brown are three of the 21 professional meteorologists that work out of the Gray office, riding herd on Maine and New Hampshire weather on a daily basis.

Wednesday, their time and attention was drawn to the winter storm, wreaking havoc across the Midwest. The storm turned north somewhere over Missouri Tuesday night and exited the U.S. over Chicago.

If that was it, Maine’s weather Wednesday would have looked like it did last week: rain and warm temperatures.

But the low-pressure system north of Chicago was joined by a second low just off the coast of Long Island. Together, they were funneling warm, Atlantic moisture right into cold Arctic air directly over Maine.

The result was a bad storm, expected to taper off to rain Wednesday night and devolve into heavy winds Thursday. Frigid cold returns over the weekend and will probably stick around. 

The weather service staff creates two basic products: a short-term forecast, good for the next 48 hours and the long-term forecast for the next seven days. They use those forecasts to create aviation and marine forecasts, weather watches and storm warnings.

Those products rely on several computer-generated models combined with a meteorologist’s skill and experience.

In the case of Wednesday’s storm, the two main weather models disagreed.

The North American Model called for heavy afternoon snow
followed by rain. The Global Forecast System predicted less snow and a quicker recovery.

“The models are very important, but they don’t tell the whole story,” Jensenius said. “It takes the skill of the meteorologist, familiar with local conditions, to interpret those models and build a forecast.”

Once a forecast is complete and has been vetted by staff members, it’s sent out. The push of a button and a computer program generates the text that is simultaneously uploaded to the Internet and read live over the local weather radio stations.

And it doesn’t end there, Hayes said. He continues monitoring the forecast throughout the morning, making sure snow falls when and where predicted.

“The more data we have the better,” he said. “That’s why the weather balloons are so important. They tell us the levels of temperatures in the air and wind speeds better than anything, even the radar.”

Weather stations around the world, just like the one in Gray, send up weather balloons simultaneously twice each day at 6 a.m. and 6 p.m. EST. At the Gray station, the balloons are launched from a platform surrounding a white sphere up from the main facility.

Each helium-filled rubber balloon carries a small carton of scientific gear roughly the size and weight of a half-dozen eggs, according to hydro-meteorologist Brown.

It includes thermometers, altimeters, a GPS receiver and a transmitter to relay that data back to the Gray station. The balloon is usually aloft for two hours before it pops, and meteorologists in Gray lose track of the package, borne now by an orange parachute.

The balloon launched Wednesday morning lasted 93 minutes, traveling about 126 miles to the east and soaring to 19,000 feet before bursting.

Gray meteorologists use the data to track wind patterns, temperature layers and barometric pressure. All of the data is compiled in Gray and sent off to a Washington, D.C., clearinghouse, then shared with the world. Gray gets the world’s data back, too, useful for tracking weather patterns as they wind their way to Maine.

Eventually, data collectors drift back down to Earth. Each contains a mailing label and directions to send it back to the weather service’s Washington, D.C., offices.

“Most of ours wind up in the ocean,” Brown said. “We don’t get those back.”

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Jim Hayes, right, briefs Eric Sinsabaugh on weather warnings and other overnight happenings at the National Weather Service Station in Gray just before a snowstorm hit Wednesday. Hayes and Sinsabaugh, both meteorologists, constantly monitor the weather on their shifts and update forecasts as needed.

The “Snow Miser” is the unofficial mascot of the National Weather Service Station in Gray.

Jim Brown inflates the morning weather balloon with helium before launching it at 6 a.m. Wednesday from the National Weather Service Station in Gray. The weather station sends up two balloons every day to check barometric pressure, temperature, wind speeds and other factors that affect weather.

Jim Brown takes a call from a weather spotter as snow begins to fall outside the National Weather Service Station in Gray on Wednesday.