Big Bear chain requirements: SR-18, SR-330, SR-38 and Mountain High

You need chains for Big Bear whenever Caltrans posts R-1, R-2 or R-3 on the mountain highways: SR-18 from San Bernardino or Lucerne Valley, SR-330 from Highland, or SR-38 from Redlands. Controls usually start below Running Springs, Snow Valley or Onyx Summit. Today's status is shown above.

The four roads to Big Bear

• SR-330 from Highland to Running Springs. The fastest way up from the freeways: a steep grade with three passing lanes that Caltrans reports as its own checkpoints. It joins SR-18 at Running Springs.
• SR-18 from San Bernardino. Up Waterman Canyon to the Crestline junction, then east along the Rim of the World through Running Springs, past Snow Valley and along the lake from Big Bear Dam.
• SR-38 from Redlands. The longer, quieter way through Mentone, Angelus Oaks and over Onyx Summit, the highest point of any of the routes, into Big Bear City.
• SR-18 from Lucerne Valley. The desert-side climb from the north. It is lower and drier than the front-side roads and is often the way in when 330 and 18 are under control or closed, though it gets its own controls in a cold storm.

The Big Bear page lists every Caltrans checkpoint on all four with its current level, message signs and cameras, refreshed every 3 minutes.

Where the controls go up

Caltrans District 8 posts Big Bear's controls, and they tend to start where the road first holds snow: on the SR-330 grade between the passing lanes and Running Springs, on SR-18 between Running Springs and Snow Valley, on SR-38 between Angelus Oaks and Onyx Summit, and on the Lucerne Valley side above Smart Ranch Road. Inside the valley, the roads around the lake and up to Snow Summit and Bear Mountain are usually clear of controls a day after a storm but stay icy in the shade. Chain installers work the SR-330 and SR-18 grades during storms.

Mountain High and Wrightwood

Mountain High is on SR-2 just west of Wrightwood. From Los Angeles the winter route is I-15 up Cajon Pass, SR-138 west, then SR-2 through Wrightwood to the resort. The Angeles Crest Highway, SR-2 from La Cañada Flintridge, is gated closed on its upper section for the winter, usually from the first big snow until spring, so do not plan on driving it from the west. Caltrans posts controls on SR-2 between Wrightwood and the resort and on SR-138, and Mountain High's page lists them.

What a storm usually looks like

Southern California mountain storms are short and intense. Controls typically go up as the snow arrives, rise to R-2 within hours, and drop again the next day as the sun returns, so the same road can need chains at 8 am and nothing at noon. The front-side grades close for spinouts and, on the busiest weekends, because there is no room left in Big Bear; the CHP then holds traffic at the bottom of SR-330 and SR-18. Requirements change without notice, and the message boards at the bottom of each grade are the last word before you commit to the climb.

What the levels mean for your car

Under R-1 you need chains unless you have snow-tread tires (M+S, M/S, MS or the mountain snowflake symbol); under R-2 unless you drive a 4WD or AWD vehicle with snow-tread tires on all four wheels; under R-3 everyone chains up. Exempt vehicles must still carry chains, and the checkpoints at Running Springs and Snow Valley do turn cars around. See R-1 vs R-2 vs R-3, chains for AWD, 4WD and snow tires and how to put on chains.

How to know if you need chains for Big Bear today

1. Look at the Big Bear and Mountain High chips in the live strip above for the worst level on each route.
2. Open the Big Bear page for the level at every checkpoint on SR-330, SR-18 and SR-38, with the cameras.
3. Check Caltrans QuickMap (quickmap.dot.ca.gov) or call 1-800-427-7623, the official sources.
4. Read the message boards at the bottom of the grade, and always carry chains.