Following Chinese balloon flight, WRTV gets insight into how weather balloons work

INDIANAPOLIS — After a massive balloon suspected of being used by China was found over the United States last week, WRTV is learning more about how balloons that look similar are used to help with forecasting.

Dozens of real weather balloons are sent up twice a day from National Weather Service offices around the United States.

"They're small," said NWS meteorologist Ted Funk. "Nothing like the one that's been in the news."

U.S. officials say the balloon that flew over the United States was 200 feet tall.

The balloon was roughly the size of an airport control tower and “probably" weighed "in excess of a couple thousand pounds,” according to Gen. Glen VanHerck, commander of North American Aerospace Defense Command (NORAD) and U.S. Northern Command.

Across the country, roughly 90 balloons launch just before 6 a.m. and again just before 6 p.m., according to Funk.

The wind carries the small aircraft, and the balloon expands as it rises.

"It has instrumentation on it that gives us temperature, humidity, pressure, wind direction, wind speed — things of that nature," said Funk.

The National Weather Service in Indianapolis does not launch balloons, but the closest stations that do conduct launches are located just north of Cincinnati, Ohio and near Springfield, Illinois.

WRTV meteorologist Todd Klaassen says the balloons are in the air for only a couple of hours.

"Essentially they get to a certain height, usually around 60,000 feet and then they just pop," Klaassen said.

The radiosonde, which is the small data-collection device connected to the balloon, slowly falls back down to the earth with a little parachute.

Klaassen says these weather-data collection balloons only travel short distances and do not span several states.

The Chinese balloon was spotted over Montana and later downed off the Carolina coast.

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Brian Branch/AP