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

Last night, a weather balloon was sent up.

From BBC • May 31, 2024

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

If you sent up a weather balloon first thing in the morning, it might encounter warmer air just above Earth’s surface before detecting progressively cooler temperatures as it rises higher.

From Los Angeles Times • Aug. 1, 2023

Prior to the launching, the crew had sent up a small weather balloon to check the winds at lower levels.

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