Blessed blast of moisture now streaming into California from the Pacific comes from as far away as the Philippines

By Tom Yulsman | March 5, 2016 7:18 pm
Atmospheric moisture

Animation of total precipitable water in the atmosphere March 2-5, 2016. (Source: Space Science and Engineering Center, University of Wisconsin)

As I’m writing this, rain and snow has finally arrived in California — and as the animation above shows, some of that moisture has traveled an exceedingly long distance.

As in all the way across the Pacific Ocean.

The animation shows the evolution of total precipitable water, or TPW, in the atmosphere for 72 hours between March 2 and 5. If you could convert all the water and water vapor contained in the atmosphere, from top to bottom, into the liquid phase, TPW is what you’d wind up with. The deepest reds in the animation above show TPW amounts in excess of 2.4 inches.

This is the feedstock for storms, including the one now hitting California.

Note that long tongue of moisture stretching all the way from the Philippines on the western side of the Pacific to the west coast of North America. Also check out a shorter tongue reaching from the Hawaiian Islands in the central Pacific. These are classic atmospheric rivers of moisture that tend to spray California during its wet season (except, of course, when it is experiencing a drought). They are even more common during El Niño events, like the one still going on.

What you’re looking at in the animation is what has been loaded up for California in the current storm, which is expected to last into Monday. Very heavy snowfall of up to 4 inches per hour is expected in the Sierra Nevada Range tonight (Saturday). By Monday, some areas could get up to two feet.

And this is just the first round. Another blast of precipitation is forecast to hit next Thursday night into Friday.

Here’s the forecast for total precipitation over seven days, starting Sunday March 6 and ending on March 13:

A lot of moisture forecast for the West Coast.

The forecast for total precipitation between March 6 and 13, 2016. (Source: NOAA)

Check out those 16 inches of water forecast for Northern California. That’s impressive! So is the blob of heavy precip totals forecast for a region stretching from Texas and Oklahoma east across the lower Mississippi Valley, and up to Missouri and Illinois.

These two things are not unrelated. El Niño forms a link between them. For more information, check out this detailed post at Weather Underground.

If it really does pan out this way, California will get a nice boost to its snowpack, and a desperately needed dose of drought relief. But at this late time in the wet season, it would take a veritable meteorological miracle to bail the state out of what has been estimated to be the worst drought in 1,200 years. We can, however, hope for some significant measure of relief.

  • OWilson

    What a difference a week makes!

    Was it really only a week ago when you posted:

    “California almost out of time for drought relief”?

    “The Climate Prediction Center’s one-month outlook shows at best a 40 percent chance for higher than normal precipitation in California”.

    Today we have this:

    Accuweather: :

    “Storms to pound California with flooding rain, mountain snow into Monday”

    Those Climate Prediction Center’s one month outlook ain’t all they’re cracked up to be.

    How accurate do you think they will be for the weather in a 100 years, (within a degree or so?) :)

  • Mike Richardson

    I wish we could give a little more of the rain we’ll be getting this week to California. On top of an early spring, in Louisiana we’re now looking at estimates of between 6-10 inches of rainfall from Tuesday to Thursday, based on the latest news today. It’s a shame we can’t share the wealth.

  • Mike Richardson

    As an update for how this system played out this week, we’ve just had some record-breaking precipitation in Louisiana the past few days. Rainfall totals around my home in southeast Louisiana were over a foot (13.5 inches), but north Louisiana really got hammered with nearly two feet (23.5 inches) in West Monroe. Quite a few roads are impassable throughout this state, and with some of the poorest bridges in this country, we’ve just had a few collapse from the flooding. The meteorologists were calling it a “thousand year” rain event, but it’s pretty similar to the flooding we got from Hurricane Isaac a few years back, though there may be worse flooding as the rivers swell from the heavier rains north of us.



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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