Don't Count On El Niño For Sierra Snowpack
Despite predictions for a strong El Niño to bring above-average rain to most of California, forecasters say it won't likely help where it's most needed. Capital Public Radio's Ed Joyce reports.
The NOAA Climate Prediction Center seasonal outlook does not forecast where or when snowstorms may arrive, nor does it project seasonal snowfall totals. Snow forecasts are determined by the strength and track of winter storms, which are not predictable more than a week in advance.
But El Niño isn't expected to increase snow in one of the areas hardest hit by the drought: the central and southern Sierra Nevada.
"And this has greatly impacted agriculture in the southern and central valley in California, one of the major agricultural producing areas in the country."
NOAA hydrologist Alan Haynes says that's because runoff was minimal after the Sierra snowpack hit a record low last April.
"These record-low snowpacks combined with near record-low seasonal precipitation translated into record-low three-year runoff volumes for the Tulare and San Joaquin Basins, plus a record low one-year runoff for the Tulare Basin."
He says the Sacramento Basin had its fourth lowest 3-year runoff.
Haynes, who works in the California-Nevada River Forecast Center, says a strong El Niño offers less certainty for a wetter-than-normal winter in northern California.
And above-average temperatures are forecast across much of the western U.S. which pushes the freezing level to higher elevations.