This story was updated to correct spelling in headline. An atmospheric phenomenon called a Pineapple Express is expected to bring heavy rains and snowfall to California and the Northwest this week.

Atmospheric rivers are a plume of moisture that extend across the Pacific to near Hawaii. When they hit land they can cause heavy rains and snow. Here’s a look at the phenomenon: ...

The deluge of snow in the mountains is coming from a weather pattern called the Pineapple Express. Large scale winds flow over our oceans. They're called Trade Winds. Typically in the tropics ...

Call it an atmospheric river, a Pineapple Express or just weather, but some parts of California and the U.S. Northwest are being slammed by up to foot of rain before the storm runs out of moisture ...