weather balloon

American  

noun

Meteorology.

1. sounding balloon.

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weather balloon Scientific  

1. A balloon used to carry instruments aloft to gather meteorological data in the atmosphere. Weather balloons are tracked by radar, Global Positioning System, or theodolites. The balloon itself usually contains devices to measure temperature, pressure and humidity, although it can contain specialized devices to measure the ozone in the ozone layer. Filled with hydrogen or helium gas, weather balloons can reach 35 km (22 mi) in altitude before disintegrating due to the decreased pressure of the lower stratosphere.

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Etymology

Origin of weather balloon

First recorded in 1935–40

Example Sentences

Soon after, twitchy soldiers defending Los Angeles unleashed a barrage of antiaircraft fire at what was later suspected to be a stray weather balloon.

From The Wall Street Journal • Mar. 13, 2026

Meanwhile, the weather service has begun halting weather balloon operations at multiple locations due to staffing shortages, reducing the amount of data that’s available.

From Los Angeles Times • Jul. 6, 2025

China claimed the aircraft was a weather balloon that had been blown off-course, but the U.S. said it was carrying sophisticated intelligence-gathering technology.

From Seattle Times • Jan. 9, 2024

China denied the balloon was engaged in spying and said it was a weather balloon.

From Washington Times • Jun. 21, 2023

As he closed on the spot he suddenly noticed what he first thought was a weather balloon.

From The Report on Unidentified Flying Objects by Ruppelt, Edward J.