Coming to SoCal, "Atmospheric River" Could Help Water Supply

Pacific moisture is streaming toward the West Coast, and is forecast to produce incredible amounts of rain and mountain snow.

By Conan Nolan
|  Friday, Nov 30, 2012  |  Updated 6:21 AM PDT
View Comments (
)
|
Email
|
Print
Pacific moisture is streaming toward the West Coast, and is forecast to produce incredible amounts of rain and mountain snow. This heavy precipitation-producing weather system flows along a phenomenon scientists refer to as the

Conan Nolan

Pacific moisture is streaming toward the West Coast, and is forecast to produce incredible amounts of rain and mountain snow. This heavy precipitation-producing weather system flows along a phenomenon scientists refer to as the "atmospheric river." It's a low-lying stream of moisture that can be beneficial for the water supply in Southern California. Conan Nolan reports for the NBC4 News at 5 p.m. on Nov. 29, 2012.

advertisement
Photos and Videos

Afternoon Weather Update: Thursday Nov. 29, 2012

"It's never not going to be rainy between now and Monday," says NBC4 forecaster Fritz Coleman. Three storm fronts will pass through the Southland over the next few days, bringing mist at best, and moderate rain at worst.
More Photos and Videos

Pacific moisture is streaming toward the West Coast and is forecast to produce incredible amounts of rain and mountain snow.

This heavy precipitation-producing weather system flows along a phenomenon scientists refer to as the “atmospheric river,” a low-lying stream of moisture that can be beneficial for the water supply in Southern California.

“An atmospheric river is a constant flow of moisture in one area because of stationary weather systems, relentless weather systems,” said NBC4 forecaster Fritz Coleman.

The one currently hovering over Northern California is delivering a small amount of rain to the south, with more to come later. There have been times when atmospheric rivers have ended up over Southern California which contributes to something called an “arc storm,” when the region gets too much water.

“The winter of 1861-62, it rained for 45 days straight in California and it was said to have been flooded from mountain to mountain from the San Gabriels to the Palos Verdes Peninsula,” said Dr. Lucy Jones, with the U.S. Geological Survey.

Although atmospheric rivers can cause severe flooding, they are a very important contributor to regional water supply.

“That rain storm that we had [Thursday] is really hitting that watershed,” said Debra Man, Metropolitan Water District of Southern California. “It flows down, goes through the delta, then goes through the California aqueduct [and] they serve our service area.”

Follow NBCLA for the latest LA news, events and entertainment: iPhone/iPad App | Facebook | Twitter | Google+ | Instagram | RSS | Text Alerts | Email Alerts

Get the latest headlines sent to your inbox!
View Comments (
)
|
Email
|
Print
Leave Comments
What's New
Running Dry
Coverage of the California drought. Read more
Follow Us
Sign up to receive news and updates that matter to you.
Send Us Your Story Tips
Check Out