Snowflakes were dancing in the hills above Interstate 5 on the Grapevine Sunday, as softball-sized rocks at one point bounced onto the main highway from Central California to Los Angeles and the Southland.
Snowplows made regular shuttles up the four-lane southbound freeway to shove aside rocks that rolled onto the pavement between Grapevine Road and Fort Tejon, the site of a hillside that caught fire months ago. A large rockslide was reported in heavy rain at 11 a.m., but all lanes were cleared within an hour, CHP officers said.
At 2:30 p.m., a seven-mile backup was reported by the CHP on California 99, as drivers encountered to slow vehicles heading up from the San Joaquin Valley floor into the mountains of northern Los Angeles County. Traffic was also backed up on Interstate 5 as the two freeways merge and head towards the mountain pass gateway to the Southland.
The eight-lane freeway between Los Angeles and points north was wet, but mostly flowing slowly in the mountains. At least one driver hyrdoplaned his car just south of the summit, and it rolled off the road, but he was not injured.
The forecast was for the rain to yield to snow in the afternoon, and 60 mile-per-hour winds were forecast as well. The National Weather Service posted a winter storm advisory and told people to bring jackets and blankets.
Commonly called the Grapevine, Interstate 5 reaches 4,160 feet above sea level at Lebec, 80 miles north of the Los Angeles Civic Center. And the snow level was predicted to drop down to the 3,500 foot contour in the afternoon, with a “dusting” in the 2-inch range predicted by tonight.
It’s not the snow that causes problems on the 5, it’s the ice that forms when snow hits the pavement, melts, trickles across the broad pavement and then freezes. Mammoth pileups have been the tragic result in years past.
Caltrans officials and the California Highway Patrol officers have 60 years experience in this, and a network of ice detectors and human observers watching for ice. Gates are shut on the northbound freeway lanes at Parker Road in Castaic, and southbound 5 in Kern County, when ice becomes a threat.
That displaces the 77,000 vehicles that use the Grapevine on an average busy day, according to Caltrans traffic counts. There are only three freeway passes linking central and southern California, and of them, Interstate 5 has the most treacherous winter storms.
The nearest detour to the 5 is California 58 at Tehachapi Pass, which also has occasional snow and ice closures. It crosses the mountains at 3,771 feet at Tehachapi Pass.
Drivers in the Southland can reach the 58 via Highway 14 or Interstate 15, which have their own passes with occasional snow problems: the 14 Freeway at 3,225-foot summit near Palmdale, and the 15 Freeway at Cajon Pass, at 4,100 feet.
The 14 and 15 freeways see occasional snow closures, and rain was predicted for those freeways Sunday.
The third route, U.S. 101 on the coast, tops out at 1,500 feet above San Luis Obispo, and has been closed by snow only once in recent decades.
Back on the Grapevine, the forecast for Sunday was snow only down to between 3,500 and 4,500 feet Sunday.
Higher than that, 2-4 inches of snow was forecast.
–City News Service