Months after the conclusion of one of the
strongest El Niños in history, the weather
system’s lesser-known sister, La Niña, has
finally made her arrival. Unlike El Niño,
which occurs when ocean temperatures
in the Pacific become unusually warm,
La Niña cools the surface of the tropical
Pacific, altering the storm track over North
America and other parts of the world.
El Niño was blamed for last year’s balmy
winter in the Northeast and soaking rains
in the drought-stricken West; La Niña will
have the opposite effect, ushering in wetter,
cooler conditions in the northern states
and exacerbating dry conditions across
the South. The weather system “is likely
to contribute to persisting or developing
drought across much of the southern U.S.
this winter,” Mike Halpert of the National
Oceanic and Atmospheric Association, tells
CNN.com. An ongoing drought in Southern
California also is likely to continue. This
La Niña isn’t particularly strong, and is
expected to last only until spring.