General Discussion

Twice a day — at 8 a.m. and 8 p.m. ET — meteorologists simultaneously launch the balloons, which are equipped with instruments called radiosondes that measure temperature, humidity and wind speed. They rise about 15 feet per second for two hours, traveling through layers of the atmosphere and sending pings of data back using radio waves.

When the air gets too thin, the balloons pop and fall back to Earth with little parachutes — mission complete.

Data from the balloons feeds into weather models that are the backbone of forecasts across the United States, whether they’re delivered by a local television broadcaster or on your iPhone.

But many of the release sites — at least 10 in the continental United States — have suspended or limited launches because of the Trump administration’s cuts to the National Weather Service staff.