Storm front over Lake Superior (US)
Click on image for full size
Courtesy of EPA

Weather Fronts

Weather fronts can cause clouds, rain, thunderstorms, gusty winds, and even tornadoes. Usually the skies clear once the front has passed.

Weather fronts happen because not all air is the same. In some places, air is warm and humid. In other places air is cool and dry.  A weather front is where two different types of air meet.

Often the air is unsettled at a front. This can cause clouds and storms. Some fronts do not cause weather events, just a change in temperature. A few fronts that form in the tropics can develop into tropical storms or hurricanes.

Fronts move over time as the air moves. The direction that fronts move is often guided by high winds. Mountains can change the direction that a front is moving.

There are 4 different types of fronts: cold fronts, warm fronts, stationary fronts, and occluded fronts.

Last modified August 12, 2009 by Lisa Gardiner.

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Rain

Raindrops form when tiny water droplets collide together in clouds to form bigger ones. When they get too heavy, rain falls out of the clouds. Rain is more than 5mm in diameter. The types of clouds that...more

Thunderstorms

Thunderstorms are one of the most exciting and dangerous types of weather. Over 40,000 thunderstorms happen around the world each day. Thunderstorms form when very warm, moist air rises into cold air....more

Wind

Wind is moving air. Warm air rises, and cool air comes in to take its place. This movement creates the winds around the globe. Winds move at different speeds and have different names based on their speed....more

Exploratour - The Atmosphere of Mars

On Earth, cold fronts occur when heavy cold air pushes lighter warm air upwards. Cumulus clouds form and usually grow into thunderstorms. Rain, snow, sleet, and hail can occur with a cold front on Earth....more

Cloud Formation and Weather Fronts

Weather fronts can cause clouds to form. Fronts happen when two large masses of air collide into each other at the Earth's surface. Warm fronts produce clouds when warm air replaces cold air by sliding...more

Rainbows

Rainbows appear in the sky when there is bright sunlight and rain. Sunlight is known as visible or white light and is actually a mixture of colors. The sun's rays pass through millions of raindrops. A...more

The Four Seasons

It takes the Earth one year to travel around the sun one time. During this year, there are four seasons: summer, autumn, winter, and spring. Each season depends on the amount of sunlight reaching the...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA