The Winter Outlook issued Thursday by federal forecasters said complete drought recovery is "unlikely this winter" and showed above average temperatures for the Western U.S.
"While drought may improve in some portions of the U.S. this winter, California's record-setting drought will likely persist or intensify in large parts of the state," according to the outlook from NOAA's Climate Prediction Center.
The forecast said "nearly 60 percent of California is suffering from exceptional drought – the worst category – with 2013 being the driest year on record. Also, 2012 and 2013 rank in the top 10 of California’s warmest years on record, and 2014 is shaping up to be California’s warmest year on record."
The report predicted some improvement in the California drought.
"Winter is the wet season in California, so mountainous snowfall will prove crucial for drought recovery," according to NOAA. "Drought is expected to improve in California’s southern and northwestern regions, but improvement is not expected until December or January."
“Complete drought recovery in California this winter is highly unlikely. While we’re predicting at least a 2 in 3 chance that winter precipitation will be near or above normal throughout the state, with such widespread, extreme deficits, recovery will be slow,” said Mike Halpert, acting director of NOAA’s Climate Prediction Center.
The NOAA Western Region Climate Director, Kevin Werner, said groundwater sources in California are nearly tapped out.
"The groundwater has been significantly, in many cases, severely depleted, this year and therefore, going forward, is a diminishing resource that the state can count on for augmenting the state's water supply," said Werner.
At the end of August, 154 of the largest reservoirs held about 36 percent of capacity, said Werner.
"Shasta Reservoir, the state's largest, is at only 25 percent of capacity," said Werner.
He said California water supply will be challenged under the forecast.
"California is now exceptionally vulnerable to water shortages if precipitation continues to be low," said Werner. "The situation is unlikely to change even if we get an average precipitation year. It will take significantly above-average amounts of precipitation to refill reservoirs and recharge groundwater in the state."
NOAA forecasters did add that other outcomes are possible, but "less likely."