Climate & Weather

Sometimes a lightning storm heralds sightings of St. Elmo's Fire. What causes the mysterious glow sailors interpreted as a sign of salvation?

By Julia Layton

Every night on the news, the weatherperson reports the UV index. What is the UV index and how is it calculated?

What causes the seasons? Why are the seasons reversed in the Northern and Southern Hemispheres? And if the Earth moves in an elliptical orbit around the Sun, why don't we have two summers and two winters every year?

By Sascha Bos

You may have heard that you can figure out how far away lightning is by how long it takes for the thunder to arrive after you see the flash. Is this true? How do you calculate it?

Why is it colder at the top of a mountain than it is at sea level? Heat rises, and the top of a mountain is closer to the sun, so shouldn't it be hotter at the top of a mountain?

By HowStuffWorks.com Contributors

Precipitation can vary from rain to snow when the temperature is below freezing. Why does precipitation not always fall as snow when it's below freezing?

We can usually see rainbows right after a rainstorm on a warm Spring day. These giant colorful arcs stand out against the dark rain clouds. Have you ever wondered what causes this phenomena? Find out how rainbows are created in this article from HowStuffWorks.

By Austin Henderson

Tornado chasers generally stay about a mile away from the tornado itself -- but not IMAX cinematographer Sean Casey. He has built a Tornado Intercept Vehicle and hopes to withstand a direct hit. Check it out.

By Tracy V. Wilson

Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides from power plants, cars and factories. Find out how acid rain is produced, how it affects natural and man-made objects and how governments aim to reduce it.

By Sarah Dowdey

A perfect climate means different things to different people. These 10 countries span the globe and offer a wide range of climates to satisfy any taste -- hot, cold or in-between.

By Jennifer Horton

Is hurricane intensity increasing? It all depends on who you ask. How have scientists come to so many different conclusions about the ferocity of these seasonal storms?

By Jessika Toothman

Heavy snowfall is just one mark of a bad snowstorm. But the biggest snowstorms of all time also brought strong winds and in some cases, major power outages.

By Ed Grabianowski, Sarah Gleim & Jesslyn Shields

Iceland? The North Pole? Antarctica? There are a lot of super cold places on this planet, but which one can claim bragging rights as the coldest place on Earth?

By Mark Mancini

It might seem that the constant rushing of water over a falls would keep it from freezing, but that isn't always the case. Check out the science behind the phenomenon of the frozen waterfall.

By Mark Mancini

Dusk is a beautiful time of day. So is twilight. But when does one turn into the other? And did you know there were three versions of each?

By Valerie Stimac

Understanding a tornado watch vs. warning is the difference between preparing for a potential disaster or immediately seeking shelter.

By Yara Simón

In 2014, scientists observed a space hurricane for the first time; they reported their findings this year. But what's a space hurricane - and do we on Earth have to worry about with them?

By Valerie Stimac

The four seasons experienced by Earth's midlatitude regions are being gradually altered by global warming - but a climate expert says they won't completely go away.

By Patrick J. Kiger & Desiree Bowie

When a hurricane or flash flood strikes a city, it can leave residents stranded in their cars, homes or other buildings waiting for rescue. How do rescue teams know where to go first?

By Laurie L. Dove

"Nor'easter" is one of those words that makes you think of an old mariner scanning the horizon for a pending storm. What does it really mean - and why don't we say "northeaster"?

By Laurie L. Dove

Have you ever wondered how weather stations gather all of their data? Even though technology for predicting the weather has improved, simple weather balloons do a lot of the hard work every day.

By Tristin Hopper

Though they're outranked by other, more dangerous natural phenomena, dust storms can still do serious damage to life and property. What causes these massive storms?

By Vicki M. Giuggio

Polar temperatures are changing more rapidly than equatorial ones, making the jet stream slower and wider, and extreme events longer-lasting.

By Jesslyn Shields

We've all seen shots of meteorologists fighting gale-force winds to report on storms. So just how high can the winds get before the reporters are knocked off their feet?

By John Perritano

The danger to the iconic statues is now greater than ever due to erosion and higher-energy wave action caused by climate change.

By Amanda Onion