What's Up With 2021's Weather?

From a loopy jet stream to climate change, an in-depth look at the factors that have shaped U.S. weather so far this year.

ImaGeo iconImaGeo
By Tom Yulsman
Apr 17, 2021 8:00 PMApr 17, 2021 8:43 PM
Tornado Damage in Alabama
On March 25, 2021, a family of six managed to survive in a closet of this house as it was torn apart by a tornado in Calhoun County Alabama. (Credit: National Weather Service Birmingham, Alabama via Facebook)

Newsletter

Sign up for our email newsletter for the latest science news
 

On March 25, 11 tornadoes ripped through central Alabama. In a frantic attempt to survive, a family of six huddled in a tiny closet as the largest of the twisters — 1.3 miles wide and with winds shrieking at 150 miles per hour — shredded their home.

Strange as it might seem, these tornados, and an outbreak of more twisters just two days later, were linked to thunderstorms boiling up some 10,000 miles away, over the Indian Ocean. And it wasn't the only U.S. extreme weather event so far this year that was tied to things happening in the atmosphere many thousands of miles away.

Lest you think this is all somehow related to one iteration or another of the famous "butterfly effect" (for example, the question of whether the flap of a butterfly's wings in Brazil can set off a tornado in Texas), no, that's not really it.

Instead of butterflies flapping, think of the myriad instruments playing different parts in a symphony orchestra. This metaphor can help clarify the causes of a number of extreme weather events we've seen this year in the United States.

Mind you, through March, this year hasn't been particularly nasty on average for the U.S. as a whole. According to NOAA, The U.S. Climate Extremes Index was 16 percent below average.

0 free articles left
Want More? Get unlimited access for as low as $1.99/month

Already a subscriber?

Register or Log In

0 free articlesSubscribe
Discover Magazine Logo
Want more?

Keep reading for as low as $1.99!

Subscribe

Already a subscriber?

Register or Log In

Stay Curious

Sign up for our weekly newsletter and unlock one more article for free.

 

View our Privacy Policy


Want more?
Keep reading for as low as $1.99!


Log In or Register

Already a subscriber?
Find my Subscription

More From Discover
Stay Curious
Join
Our List

Sign up for our weekly science updates.

 
Subscribe
To The Magazine

Save up to 40% off the cover price when you subscribe to Discover magazine.

Copyright © 2025 LabX Media Group