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We all know it's a little cooler under a shady tree. But do trees have an effect on the five-day forecast, or even the global climate?

If you've ever looked up at the sky, you may have noticed that it frequently changes color. The sky is usually blue on bright, sunny days. Have you ever wondered why that is?

I've noticed a lot of times, especially in the spring and summer, that there is a strong, funny smell after it rains. Sometimes it is a good smell, and sometimes it is unpleasant. What causes this smell?

Did bunnies just attack that sailboat, or was it a narwhal playing with a school of fish? Are you going crazy, or are you just watching the clouds?

Questions about climate change are answered by researchers.

In the southeast United States, four different types of water can fall from the sky if the weather is close to freezing. Sometimes rain falls, sometimes freezing rain, sometimes sleet and then occasionally snow. What causes all of these different forms?

We hear about humidity in just about every weather report on the nightly news. There are several different ways meteorologists measure humidity, but relative humidity is the most common measurement. What is relative humidity, though?

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 -- shouldn't it be hotter at the top of a mountain?

What is the "heat index" that the weatherperson talks about during the summer? Also, why is the air comfortable at only 80 degrees F even though body temperature is 98 degrees F?

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?

Can Fido predict an incoming tornado? If animals can predict the weather, do we stop trusting the weatherman and start visiting the zoo to get tomorrow's forecast?

If a tornado was heading your way, you'd probably head for the hills. But for some people, it's just the beginning of a chase.

It may seem like a perfectly reckless display of aeronautical wiles, but guiding an airplane into a swirling beast of a hurricane gleans data that can save lives. The only question is, who were the crazy mavericks who attempted it first?

Watch this video about predicting winter weather on HowStuffWorks. Want the most reliable forecast of how severe this winter will be for the U.S. and around the world? One scientists says just watch Siberia's weather come October.