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

If the pillars are very short or resemble something closer to a halo near the Earth’s surface, that means the ice crystals are hovering very close to the ground, indicating an extremely cold air mass. Kathryn Prociv, Washington Post, "These ‘ice pillars’ make it look as if a Canadian town is being abducted by aliens," 19 Jan. 2018 These big swirling air masses normally hover over the North and South poles in the wintertime. David Grossman, Popular Mechanics, "What Is a Polar Vortex? The Frigid Weather Pattern Explained," 16 Jan. 2019 The end result in this region is that air masses are pulled together and upwards a little more strongly, bringing in more moisture that condenses into rain clouds as the rising air cools. Scott K. Johnson, Ars Technica, "Carpeting Sahara with wind and solar farms could make it rain," 8 Sep. 2018 Skies will clear overnight, and a much more comfortable air mass will be in place by tomorrow morning. Greg Porter, Washington Post, "PM Update: Scattered showers early, clearing overnight. Warm and comfortable on Monday.," 24 June 2018 With a seasonably mild air mass (highs today will be near 58), snow levels have risen well above the passes to near 6,000 feet., "Portland metro Thursday weather: Rain, more rain and then some rain - high near 58," 5 Apr. 2018 The center of a storm will often form along the boundary of a weather front, the transition zone between two air masses of different densities. Steven Senne, National Geographic, "Wind, Snow, and Floods—What You Need to Know About the Northeast's Dangerous Winter Storm," 2 Mar. 2018 Temperatures are expected to top the 90-degree mark again Thursday, but thunderstorm activity is expected to be more widespread as a cold front moves through the area, ushering in a noticeably cooler and less humid air mass for the weekend. Tom Skilling,, "City's hot, muggy Fourth, the warmest in 6 years," 4 July 2018 But this is not just about temperature; the movement of air masses also controls precipitation patterns and storm tracks. Scott K. Johnson, Ars Technica, "Mad scientists flip the Earth’s spin in climate models, watch water go nuts," 17 Oct. 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

15 Apr 2019

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

Rhyming Dictionary: 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).


to move or proceed with twists and turns

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Latin Quiz

  • roman forum
  • Which of the following months comes from a Latin word for “ten”?
Spell It

Can you spell these 10 commonly misspelled words?


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!