How Grounding Weather Balloons Could Hurt Forecasting Accuracy Just As Storm Season Starts

As severe weather season ramps up, the reliability of local weather forecasts could be compromised as the National Weather Service cuts back on weather balloon launches in about a dozen places to absorb staff cuts.

Weather balloons — more precisely, the radiosondes attached to them — are a decades-old tool meteorologists use to peek into the upper atmosphere for vital forecasting data. The advantage for meteorologists is the ability to put out advance forecasts with reliable predictions of the strength, intensity and duration of storms on the ground.

Balloons are typically launched simultaneously twice a day at 8 a.m. and 8 p.m. Eastern Time, from about 100 sites across the country and in the Pacific and the Caribbean. In eight of the sites experiencing cuts, launches will be limited to one a day. At three others, balloons are grounded. Synchronized launches refine the real-time data readings collected by the radiosondes that are vital for national forecasts.

The affected sites are in the northern U.S. That’s where the jet stream — a band of strong, fast-moving winds in the upper atmosphere that steer and influence the movement of weather systems — is located at this time of year.

Balloon launches were eliminated in Omaha, Nebraska; Rapid City, South Dakota; and Kotzebue, Alaska. They were cut from twice daily to once daily launches in Aberdeen, South Dakota; Grand Junction, Colorado; Green Bay, Wisconsin; Gaylord, Michigan; North Platte, Nebraska; and Riverton, Wyoming, plus previously announced Albany, New York, and Gray, Maine.

‘The Worst ‘Time Of The Year’

“For those of us east of the Rocky Mountains, this is probably the worst time of year,” the University of Oklahoma environment professor Renee McPherson told The Associated Press. “It’s the time of year that we have some of our largest tornado outbreaks, especially as we move into April and May.”

She added, “This frankly is just dangerous.”

“The really unfortunate thing is, where these balloons are now missing — the Colorado Rockies, the Wyoming Rockies, the northern and central High Plains — is where a lot of severe weather happens in the spring and summer months and [where] a lot of the storms that will impact the Great Lakes and Eastern United States first develop,” Chris Vagasky, the research program manager for Wisconet, a network of weather and soil monitoring stations across Wisconsin, told NBC News.

“We’re going to lose data because of this staffing,” Michael Morgan, an atmospheric scientist at the University of Wisconsin-Madison and former NOAA administrator, said at a news conference Monday. “And that loss of data then translates into less precise forecasts, more uncertainties in the forecast.

“Does it mean every single forecast is going to be poor? No, but it does mean that the uncertainties in our forecast will grow over time.”

Matt Lanza, a meteorologist in Houston who writes for “The Eyewall” blog, told NBC that forecast errors are a foregone conclusion.

“There’s no question it will lead to errors. It’s just a matter of how bad will it be,” he said “We know these things help with forecasts, so why are we cutting them?”

In an interview with The AP, Kristen Corbosiero, a meteorology professor at the University of Albany, said she looked at the map of launches and thought, “Wow, that is an empty area,” she told The AP. “That’s not great.”

‘This Is Not Government Efficiency’

Overall, the agency has let more than 1,000 workers go, eliminating 1 in 4 jobs, since President Donald Trump took office in January and his Department of Government Efficiency began systematically cutting the federal workforce.

“This is not government efficiency,” Rick Spinrad, a former administrator for the National Oceanic and Atmospheric Administration, told The AP. “It is the first step toward eradication. There is no way to make these kinds of cuts without removing or strongly compromising mission capabilities.”

Cutting back on launches is a big mistake that compromises the accuracy of forecasts that give the public time to prepare for life-threatening storms, meteorologists and other experts told The AP.

‘Absolutely Essential’ Forecasting Tool

Together, the 11 balloon launch sites make up about one out of nine launch locations across the United States, including parts of the Pacific and Caribbean, but they have an outsized influence on both local and regional forecasts.

But because storms and weather systems track from west to east, the data collected by weather balloons is important in developing regional and national weather forecasts that can affect everything from air travel to emergency preparedness.

“The thing about weather balloons is that they give you information you can't get any other way,” D. James Baker, a former NOAA chief during the Clinton administration, told The AP.

Baker had to cut spending in the agency during his tenure but he said he refused to cut observations such as weather balloons.

“It’s an absolutely essential piece of the forecasting system,” he said.

“Bad,” Ryan Maue, who was NOAA’s chief scientist at the end of Trump’s first term, wrote in an email to The AP. “We should not degrade our weather system by skipping balloon launches. Not only is this embarrassing for NOAA, the cessation of weather balloon launches will worsen America's weather forecasts.”

Radar, aircraft and, especially, satellite data can fill in some of the blanks with surface-level data. But that only shows meteorologists what is happening — not why the weather event is happening, its duration and other details people need to know to protect their lives and property.

“On one hand, satellites today are capable of incredible observations that can rival weather balloons at times,” Lanza wrote on “The Eyewall” blog. “And they also cover the globe constantly, which is important. That being said, satellites cannot completely replace balloon launches.

“Why? Because the radiosonde data those balloon launches give us basically acts as a verification metric for models in a way that satellites cannot,” he wrote. “It also helps calibrate derived satellite data to ensure that what the satellite is seeing is recorded correctly.”

Meteorologists can produce forecasts without that fine-resolution data from the different layers of the atmosphere, but the amount of precipitation, for example, could come down to guesswork.

“Here in New York we often have very messy weather systems where they start as snow and turn into sleet and then freezing rain and rain,” Nick Bassill, the director of the State Weather Risk Communication Center at the University at Albany in New York, told NBC. “We might have just one little thin layer that bumps you up above freezing, then suddenly your snowstorm turned into a rainstorm or freezing rainstorm.”

The Associated Press contributed reporting.