Pacific Moisture Returns to the West

news image
Special Stories
4 Apr 2018 4:32 PM
Several rounds of rain and snow will begin to impact the western United States late this week thanks to the "Pineapple Express." https://twitter.com/NWSBayArea/status/981613453172527110 The Pineapple Express---an atmospheric river of moisture originating near Hawaii---is often necessary to keep the West Coast drought-free.  However, it can bring hazardous weather in the form of flooding and mudslides.  But what is an atmospheric river? https://twitter.com/NWSBayArea/status/981190965036830720 With a milder air mass in place, mountain locations like the Sierra Nevada will contend with melting snow and falling rain.  The risk of flooding will increase. https://twitter.com/NWSSacramento/status/981581665670610944 A Flood Watch is posted for the mountains and foothills along the California - Nevada border.  Rainfall may exceed 6 inches in parts of the Sierra Nevada by Sunday. River flooding is a concern.  But what is the chance for debris flows or mudslides, especially in burn scar areas?  WeatherNation spoke with the National Weather Service Bay Area office in Monterey, California.  Meteorologist Scott Rowe explains. https://twitter.com/WeatherNation/status/981660219758411776 As you might expect with a Pacific system, the Northwest will also join in on the rain and subsequently, the threat for flooding.  Snow will be more of a concern with colder temperatures in place across the Northern Rockies and High Plains. Snow totals may approach 6 inches in the valleys, plains, and lower elevation locations.  The mountains---in Wyoming, in particular---may see snow accumulations near 12 inches. Be sure to follow WeatherNation on Facebook and Twitter for the latest West Coast forecast and other top weather stories. -Meteorologist Joe Astolfi
All Weather News
More
Another Winter System Targets Midwest and Northeast

Another Winter System Targets Midwest and Northeast

A new round of winter weather is set to take

27 Feb 2026 11:45 AM
Spring & Summer Like Temperatures for the Southwest

Spring & Summer Like Temperatures for the Southwest

This week brings some nice days to the southe

27 Feb 2026 10:10 AM
Fire Burns Through the Florida Everglades, Prompting Road Closures

Fire Burns Through the Florida Everglades, Prompting Road Closures

A fast-moving brush fire is burning across pa

27 Feb 2026 10:00 AM
Total Lunar Eclipse Visible Across North America Tuesday Morning

Total Lunar Eclipse Visible Across North America Tuesday Morning

A blood moon will soon be gracing (clear) ski

27 Feb 2026 9:00 AM
Severe Weather Hits the Southeast Thursday

Severe Weather Hits the Southeast Thursday

A busy day on Thursday resulted in several re

27 Feb 2026 3:35 AM
A Clipper Brings Additional Quick Snow to the Northeast

A Clipper Brings Additional Quick Snow to the Northeast

The Northeast has gotten another few inches o

26 Feb 2026 10:35 AM
Elevated Fire Danger Across Southern Plains

Elevated Fire Danger Across Southern Plains

Last week, multiple fires broke out across th

26 Feb 2026 1:45 AM