Supercell thunderstorm moving across northeast Colorado
Right now there are about two thousand thunderstorms going on around the world. While common, they are dramatic with intense rain, hail, wind, lightning, thunder, and even tornadoes.
cold front causing a thunderstorm
Have you ever wondered about what atmospheric conditions are needed for a thunderstorm to form?
Where Thunderstorms Happen
Some places in the United States have more thunderstorms that other areas. What is the average number of thunderstorm days in your state?
Lightning storm
Lightning is the most spectacular element of a thunderstorm. Learn how lightning forms, and how lightning leads to thunder.
A dark funnel of cloud extends below a storm. If it reaches the ground, it’s a tornado.
How Tornadoes Form
Only about one thunderstorm in a thousand produces tornadoes. So how do tornadoes form?
Where Tornadoes Happen
Tornadoes, also called twisters, are columns of air rotating dangerously fast. Find out where they happen.

A strong hurricane can spell disaster. These huge storms are the most powerful of all weather systems. Learn about how they form and the impacts they can have.

NASA simulation of hurricane Sandy approaching the east coast of the US
Tropical storms can grow into hurricanes, and hurricanes can grow into stronger hurricanes. However, only a small number of storms grow into tropical storms. Even fewer become hurricanes. Learn what is necessary for hurricanes to form.
Home in New Orleans damaged by a hurricane
When a hurricane approaches land, tremendous damage can occur to coastal cities and natural environments. Learn about the potential hazards and how to predict the amount of damage done by a hurricane when it hits.
Flooding in New Jersey neighborhood caused by Hurricane Sandy

Learn about the many factors that impact how much storm surge floods a coast as a hurricane or tropical storm comes ashore. 

Car buried in snow
Hoping for a snow day? A snow storm is just one kind of winter storm. Learn what happens when a winter storm occurs, and how this might affect us.
monsoon rains in Mumbai
Monsoons produce the very wet summers and dry winters that occur on nearly all of the tropical continents. A monsoon is not a storm like a hurricane or a summer thunderstorm, but a much larger pattern of winds and rain that spans a large geographic area – a continent or even the entire globe.
snow blowing in a field
High winds can send snow flying through the air, reducing visibility and causing power outages. That's just some of what you can expect from a blizzard.
Icy Winter Weather
When meteorologists forecast a winter storm one of the important predictions they make is the type, or types, of precipitation that are likely to fall. Will freezing rain cause an ice storm? Will ice pellets called sleet leave the ground covered in slush? Will it rain or snow?
Will it rain, sleet, or snow?
Can you predict if it will rain, sleet, or snow? Test your forecasting skills!
A large hailstone
Snowflakes are not the only type of icy precipitation. Find out about other types of ice that fall from the sky.
Big and small snowflake cartoon

Snowflakes come in all shapes and sizes. Here are two who like each other just the way they are. Happy Valentine's Day!

two snowflakes
Some snowflakes are made of a single ice crystal while other, more elaborate, snowflakes are made of as many as 200 ice crystals fused together.
Weather Image Gallery

Photos, diagrams, and other images related to weather.

Weather Videos

Short video clips about weather - including weather measurements and several weather

weather games and simulations
Test your knowledge with one of our games or gain a deeper understanding of weather through a simulation.
Storms and Other Weather Activities
Experience weather outside or investigate weather through data, graphs and maps. These activities range from simple explorations of snow, to more through analysis of climate change and weather.