warm front

American  

[wawrm fruhnt] / ˈwɔrm ˌfrʌnt /

noun

Meteorology.

1. a transition zone between a mass of warm air and the colder air it is replacing.

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warm front British  

noun

1. meteorol the boundary between a warm air mass and the cold air above which it is rising, at a less steep angle than at the cold front Compare cold front occluded front

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warm front Scientific  

1. The forward edge of an advancing mass of warm air that rises over and replaces a retreating mass of cooler air. As it rises, the warm air cools and the water vapor in it condenses, usually forming steady rain, sleet, or snow. On a weather map, a warm front is depicted as a red line with half circles whose curved sides point in the direction in which the warm air is moving.

2. Compare cold front occluded front See illustration at front

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Etymology

Origin of warm front

First recorded in 1920–25

Compare meaning

How does warm-front compare to similar and commonly confused words? Explore the most common comparisons:

• cold front vs. warm front

Example Sentences

A warm front arrived across the Central Coast late Tuesday and will spread south into Los Angeles through the day Wednesday, bringing with it a sprinkling of moisture ahead of the brunt of the storm.

From Los Angeles Times • Mar. 5, 2025

Since the warm front started moving in, downtown Los Angeles received about .67 inches of rain, while Beverly Hills came in at 1.8 inches.

From Los Angeles Times • Jan. 5, 2023

Lots of work from transportation crews as well as warmer temperatures allowed Snoqualmie Pass to reopen Christmas Day, and with a warm front moving through, post-holiday highway travel should continue to improve.

From Seattle Times • Dec. 25, 2022

Meteorologists attributed the weather to a warm front that had hovered above the area for an extended period, bringing with it several inches of rain.

From New York Times • Jan. 9, 2022

Northwest, scattered alto-cumulus, looks like the onset of a warm front, with the northeast quadrant moderate-high cirrus.

From A Fine Fix by Dongen, H. R. van