La Niña has arrived, fueled by colder-than-normal Pacific Ocean temperatures—and it could bring a lot of snow and severe ...

In an early sign of the winter weather that's coming, the dreaded polar vortex is making news yet again. The polar vortex is "ramping up from its summer slumber," said meteorologist Judah Cohen in an ...

La Niña is a part of a natural climate cycle officially known as El Niño-Southern Oscillation, or ENSO. The cycle swings ...