How will La Niña affect winter in the U.S.?

Forecasters are expecting another La Niña winter for the 2017-2018 season. La Niña (which means “little girl” in Spanish) disrupts large-scale climate patterns that can influence water availability, food production, human health, and extreme weather events around the globe. So what exactly is La Niña, and what might she have in store for you this winter?