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Radar, DOT cameras and live pavement conditions on the 201 miles of I-80 in California — plus closures, road work and city-by-city weather across the state.
Updated Oct 8, 2026 8:33 PM PDT · Mostly dry, damp in places
Lowest 61°F near San Francisco, California · Highest wind 15 mph near San Francisco, California
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I-80 runs 201 miles across California, but in winter the part that matters is the climb from Auburn to Truckee over Donner Summit at 7,239 ft. That is where Caltrans puts chain controls first and closes the road first, and where the weather in Sacramento says nothing about the weather at the top.
Weather data from Oct 8, 2026 8:33 PM PDT
Dry
I-80 crosses 201 miles of California, from the Nevada line to its end in the state. That is 7% of I-80's 2,900 miles.
Inside California it meets I-5 at Sacramento.
By mile marker, I-80 passes San Francisco 0 · Sacramento 83.
It carries Donner Pass at 7,239 ft, where the weather at the summit is not the weather on the approach.
22 current reports along the route. The 6 most serious are listed below. Always check with the responsible state DOT before setting off.
Off Ramp closure. Work: Pavement Work. Lanes closed: All. Near Davis, Yolo County.
On Ramp closure. Work: Highway Construction. Lanes closed: All. Near Alta, Placer County.
Mainline closure. Work: Pavement Work. Lanes closed: 1. Near Davis, Yolo County.
Mainline closure. Work: Pavement Work. Lanes closed: 1, 2. Near Davis, Yolo County.
Mainline closure. Work: Pavement Work. Lanes closed: 1, 2, 3, 4. Near Davis, Solano County.
Mainline closure. Work: Pavement Work. Lanes closed: 1, 2, 3. Near Woodland, Yolo County.
| Place | Snow a year | Snow days | Freezing nights | Freeze–thaw days | First freeze | Last freeze | Days over 90°F |
|---|---|---|---|---|---|---|---|
| Auburn | 0.9" | 0.4 | 13.1 | 13.1 | Dec 9 | Feb 15 | 57.8 |
| Truckee | 202.6" | 42.5 | 243.6 | 231.9 | — | — | 7.4 |
| San Francisco | 0" | 0 | 0.3 | 0.3 | Dec 31 | Jan 1 | 3.3 |
| Sacramento | 0" | 0 | 5.1 | 5.1 | Dec 18 | Jan 19 | 74.4 |
NOAA 1991–2020 Climate Normals, from 4 weather stations in California. A dash is a figure that station does not report, not a zero.
Every figure above is a town or a city. The summits are a different climate: Donner Pass (Donner Summit, I-80) has its own page with the readings at the top and a six-day summit forecast.
From Piedmont to Truckee, with the position of each town measured along this stretch itself — counted from the Piedmont end, not from a state milepost, so it will not match the numbers on the signs.
Places from the US Census Gazetteer and population estimates, both public domain; distances measured along this page's own route geometry.
The sign states the rule; R-1, R-2 and R-3 are what you hear on the radio. Caltrans does not post signs with those designations — they are shorthand it and the CHP use internally, which traffic reports then repeat. What is posted at the roadside is the requirement and the list of who is exempt, and which of the three levels is up decides whether snow tires are enough — or whether anything is. Caltrans is explicit that the sign wins: follow it, and any instruction from Caltrans or CHP staff at the checkpoint, even where it differs from a broadcast report or from a page like this one.
A snow-tread tire here carries MS, M/S, M+S or the words MUD AND SNOW on the sidewall and has at least 6/32-inch of tread — the same depth as Colorado's 3/16-inch, written the other way round. Chains means any approved traction device: link chains, cable chains, textile snow chains, hub-mounted and automatic chains all count, and Caltrans and the CHP can turn away a vehicle whose device does not meet the Vehicle Code.
Non-compliance is a citation from the California Highway Patrol, which is who enforces chain control rather than Caltrans; no fixed amount is published.
Which requirement is posted changes with the storm and with the elevation. This page does not carry it — QuickMap ↗ is the authority before you set off.
Source: Caltrans, checked September 22, 2026.
Summaries fetched Oct 8, 2026 5:01 AM PDT
Photo from — last answered 4 hours ago, so this is the last frame we have
Photo from — last answered 4 hours ago, so this is the last frame we have
Photo from — last answered 4 hours ago, so this is the last frame we have
Photo from — last answered 4 hours ago, so this is the last frame we have
Photo from — last answered 4 hours ago, so this is the last frame we have
Photo from — last answered 4 hours ago, so this is the last frame we have
The same live radar and road-surface data as this map, on your phone and on Apple CarPlay or Android Auto.
Weather Navigation carries the same radar and road-surface data on Apple CarPlay and Android Auto, with a weather-aware route planner, storm-cell tracking and radar that refreshes every two minutes over the US.