Friday night's relief from freezing temperatures that threaten the county's $620 million a year citrus industry was only temporary.
Much of the San Joaquin Valley, including part of Kern County, remains under a "hard freeze warning" until Tuesday morning, according to the National Weather Service.
The overnight low from Friday night to Saturday morning was 37 degrees, a merciful five degrees above the critical 32-degree freezing point that damages citrus crops, said Jim Dudley, a meteorologist in the weather service's Hanford office.
"Last night was a nice respite for citrus and for everybody else," he said. "But that respite is going to be over."
The projected overnight low tonight to Monday is 26, and the overnight low Monday to Tuesday is expected to be 28, Dudley said.
A supervisor of Kern County's Fruit and Vegetables Standardization Program said inspectors found ice crystals in navel oranges in Delano Thursday and some of that crop was likely ruined.
Plans to send inspectors out again Saturday were not carried out due to safety concerns, said supervising biologist Jennifer Stilwill.
"It's really wet and muddy out there," she said.
It will likely be several days before the full extent of the damage to local citrus is known, Stilwill said, but if temperatures go as low as projected, it's going to be ugly.
"If it was just one night, there would still be some residual heat in the center of the fruit to protect it, but when it's several nights in a row, that can really do a number on oranges. It's like keeping them in your refrigerator."
Growers have been taking cautionary measures to save what they can, including circulating warmer air around the groves and saturating the ground to keep soil warm.
There was snow in higher elevations Saturday and rain on the valley floor.
The California Highway Patrol closed State Road 58 and Interstate 5 over the Grapevine for a few hours Saturday morning due to snow and ice.
Both roadways reopened at 1:30 p.m. Saturday, but the 58 closed again shortly before 4 p.m. Access was cut off eastbound at Tower Line Road in Bakersfield and westbound west of Mojave.
No estimated reopening time had been issued as of Saturday night.
The road closure forced the Bakersfield Condors to postpone Saturday's night's scheduled hockey game against the Las Vegas Wranglers, who couldn't make it to Bakersfield.
The cold snap, part of a nationwide chill caused by a cold front from the Arctic, is expected to continue into the middle of this week in most areas.
In Northern California, officials reported three homeless people have died from exposure since Thursday, with another man having died on Thanksgiving.
Officials are warning those with elderly friends or relatives to check that their homes are heated properly and to move their plants indoors.
The Los Angeles Times contributed to this report.