A restriction is not a weather forecast
Caltrans publishes chain-control point records with a status code, location and travel direction. These are operational reports, not predictions inferred from snow icons. On the selected California corridors we show the reported code and description without translating a lack of records into an open-road claim.
Read the code and its full description
R-1, R-2 and R-3 describe different equipment requirements. Do not rely on a one-line summary to decide that your vehicle is exempt. Tire type, drivetrain, vehicle class and towing can matter. Read the current Caltrans requirements, carry the appropriate equipment, and follow posted instructions and officials on site.
Other statuses can be more important than a chain level
The data can also describe traffic being held, trucks being screened, escorts or a road closed to traffic. These are not simply different snow probabilities. Confirm the applicable section and direction with Caltrans before approaching it.
Fresh record, unchanged restriction
A report may be refreshed while its status-change timestamp remains older. We keep those times separate. Conversely, a feed fetched just now may contain old records; stale records are visibly marked and must not be relied on as current.
The state line ends this feed’s coverage
Caltrans records on Sacramento–Reno cover the selected California portion, not Nevada. Records on Redding–Ashland do not cover Oregon’s Siskiyou Summit. Use the linked neighboring-state authority for the remainder.
Official sources
Caltrans chain-control data and status chart
Reviewed October 5, 2026. Check the current source before travelling.