air mass


Definition of air mass 

: a body of air extending hundreds or thousands of miles horizontally and sometimes as high as the stratosphere and maintaining as it travels nearly uniform conditions of temperature and humidity at any given level

Examples of air mass in a Sentence

Recent Examples on the Web

Now imagine these air masses are only about 10 miles apart. Matthew Cappucci, Washington Post, "A ‘dryline’ is triggering severe weather in the Plains. Here’s what that means.," 1 May 2018 Some showers and thunderstorms will accompany the arrival of the warmer air, but colder weather returns by Sunday as another chilly air mass sweeps into the area following the passage of a strong cold front. Tom Skilling,, "More snow, then a brief spring fling," 8 Apr. 2018 With the change in air mass, Wednesday and Thursday should be pleasant, bringing dry weather and a glimpse of sun, Simpson said. Elise Takahama,, "Scattered showers will hit Boston this weekend, along with increasing clouds and humidity," 14 July 2018 And that warm and humid air mass could increase our chances of seeing some afternoon thunderstorms. Greg Porter, Washington Post, "PM Update: Severe storm chance southwest of D.C. this evening; steamy with storm chances again Monday," 13 May 2018 Things should begin to change this weekend as a cold front interacts with the hot and increasingly humid air mass over the area, triggering several rounds of showers and thunderstorms capable of producing downpours and strong winds. Tom Skilling,, "Storms to accompany weekend warmth and humidity," 13 July 2018 While the models show a warm ridge of high pressure parked over the eastern United States in the seven-to-10-day period, a cooler pool of air at high altitudes lurk to the west, which may eventually replace the toasty air mass. Jason Samenow, Washington Post, "There are growing signs we’ll get a taste of summer in about a week," 24 Apr. 2018 Over the weekend, a warm-air mass parked itself over Greater Cincinnati, the winds died off, and the rain was light and widely scattered – a classic situation for ozone pollution to boil up. Anne Saker,, "The reason Cincy's air is bad? It's summertime, and the ozone is baking," 18 June 2018 Interstate 35 is infamous for being the divider between Gulf Coast moisture from the east and more arid, desert air masses from the west. Matthew Cappucci, Washington Post, "Oklahoma wildfires ignite in ‘historic’ hot and dry weather conditions," 13 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'air mass.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

See More

First Known Use of air mass

1882, in the meaning defined above

Keep scrolling for more

Learn More about air mass

Statistics for air mass

Last Updated

30 Sep 2018

Look-up Popularity

Time Traveler for air mass

The first known use of air mass was in 1882

See more words from the same year

More from Merriam-Webster on air mass

See words that rhyme with air mass Encyclopedia article about air mass

Comments on air mass

What made you want to look up air mass? Please tell us where you read or heard it (including the quote, if possible).


lying above or upon

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Roman Mythology Quiz

  • the-triumph-of-venus-by-alessandro-magnasco
  • Boreal comes from the name of the ancient Greek god of which wind?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!