Road closed
Obey the gate or sign. Check COtrip for the reason, open routes, and updates. Wait in a safe public place if you can. A smaller road offered by a map app may be unplowed, closed, or harder than the highway.
Winter road guide
Winter driving in Colorado
Check the weather and the full route before you leave. A dry road in town can become snow, ice, or a closure at a pass. Your best plan is a ready car, extra time, and a clear point when you will wait instead of pressing on.
The trip workflow
Five checks, in order
- 1
Check the trip
Read the forecast, then open COtrip for your whole route.
- 2
Check the law
Look for active traction or chain rules on COtrip and road signs.
- 3
Check the car
Inspect tires, fluids, lights, heat, wipers, and your emergency kit.
- 4
Change your driving
Slow down, skip cruise control, and leave much more room.
- 5
Know when to stop
Do not push through a closure, whiteout, or unsafe vehicle problem.
1. Check the forecast and COtrip
Read the forecast for the towns and passes along your route, not just your start. Then open COtrip. Check road conditions, closures, cameras, travel alerts, and the route you may use if the main road closes. Check again just before you leave. On a long trip, check during a safe stop because the road can change fast.
If the hardest part of the storm will meet your drive, leaving later may be the safest move. Build time for slow traffic, plows, and a closure. A winter arrival time is a plan, not a promise.
2. Check the current traction and chain status
CDOT can activate traction and chain rules on any state highway when winter conditions call for them. The traction law is also in effect each year from September 1 through May 31 on I-70 between Dotsero and Morrison. COtrip, highway signs, and road alerts show when a rule is active.
Under CDOT's current traction-law list, the tire-only setup is AWD or 4WD with at least 3/16 inch of tread and tires marked for winter, mud and snow, or all-weather use. Look for the mountain-snowflake mark, M+S, M&S, or M/S, or a maker's all-weather rating. A vehicle that does not meet that full setup needs chains or a CDOT-approved alternative traction device while the law is active.
A passenger vehicle chain law is stricter. CDOT uses it during severe storms as the last safety step before a highway closes. When it is active, every vehicle needs chains or an approved alternative device. Check the current CDOT page for the equipment list and learn how to fit your device before the storm.
AWD and 4WD can help a vehicle move. They do not shorten a stop or make a turn safe on ice. Tires, speed, and room still matter.
Before you leave
Winter car checklist
Check these at home. A chain that does not fit or a dead flashlight will not help on the shoulder.
For tire labels and tread, use the current CDOT tire guide. If you are not sure what is on the car, ask a tire shop to show you the sidewall marks and measure each tire.
3. Change how you drive
Slow down before the road gets hard. Leave a wide gap so you can ease off the gas and brake gently. Add more room when snow, ice, curves, steep grades, or poor sight make a stop harder. Turn, brake, and speed up one at a time when you can. Sudden moves use up the grip your tires have.
- Do not use cruise control on snow, ice, or slush.
- Use low beams when snow or fog cuts your view.
- Stay back from plows and large trucks. Do not pass plows working together in a staggered line.
- Start slowing before a curve, hill, stopped line, or shaded patch.
- If the car starts to slide, look where you want to go and avoid a hard brake or sharp turn.
When the plan breaks
Closure, whiteout, or stalled vehicle
Whiteout
Ease off the gas, use low beams, stay in your lane, and do not pass. If you cannot see enough road to keep moving, use the nearest safe exit or marked pull-off you can reach. Do not stop in a travel lane.
Stopped or stalled
Call 911 and stay in the vehicle unless you face immediate danger. Turn on hazard lights and make the car easy to see. Keep the exhaust pipe clear of snow. Run the engine only as needed for heat, stay dry, and save your phone battery.
FAQ
Quick answers
Is the Colorado traction law active all winter?
It is in effect from September 1 through May 31 on the I-70 mountain corridor between Dotsero and Morrison. CDOT may also activate traction or chain rules on any state highway when conditions call for them. Check COtrip and highway signs for the current status.
Is AWD or 4WD enough for an active traction law?
Not by itself. CDOT's current rule also calls for a qualifying tire label and at least 3/16 inch of tread. A vehicle that does not meet the full tire-and-drive setup needs chains or a CDOT-approved alternative traction device. Check CDOT's current traction page before the trip.
Do all-season tires count?
Do not rely on the words all season alone. Check each tire for the mountain-snowflake, M+S, M&S, or M/S mark, or a manufacturer all-weather rating. Tread depth also matters. CDOT's tire page shows the current labels and rules.
How much following distance should I leave in snow?
There is no single gap for every road. Leave enough room to slow without a hard brake, then add more space as grip or sight gets worse. Stay well back from snowplows and large trucks.
What should I do when the road closes?
Obey the closure and check COtrip. Wait in a safe public place or use an official route that COtrip shows as open. Do not trust a map app to send you around a gate on a smaller road.
What should I do if my vehicle stalls in a storm?
Call 911, make the vehicle easy to see, and stay inside unless you face immediate danger. Keep the exhaust pipe clear of snow. Run the engine only as needed for warmth, and conserve your phone battery while help is coming.
Sources and review
Where this information comes from
This guide uses Colorado Department of Transportation and Colorado State Patrol guidance. Live road status still comes from COtrip and highway signs.
- Data used
- Current CDOT traction-law, tire, road, and winter-preparedness guidance
- Last reviewed
- July 16, 2026
- CDOT winter driving for road information, alerts, and Colorado winter travel resources.
- CDOT winter driving preparedness for vehicle checks, emergency supplies, and snow-driving habits.
- CDOT passenger traction and chain laws for current activation rules, equipment choices, and approved devices.
- CDOT vehicle and tire safety for tire labels, tread depth, and winter tire guidance.
- COtrip traveler information for current road conditions, closures, cameras, and travel alerts.
- Colorado State Patrol stopped or stalled guidance for what to do while stranded in snow or cold.
- Colorado State Patrol Winter Ready for tire, vehicle, mountain-road, and driving tips.
Use this carefully: Road conditions, closures, and law activations can change during a trip. Check COtrip, road signs, and CDOT's current traction-law page before leaving and again after a long stop.
Next steps
Check the road, then keep the car ready
Use the live state map before a trip, or keep going with the Colorado car guides and local driving notes.
Live conditions
Open COtrip
Check current road conditions, cameras, closures, alerts, and traction status for the whole route.
Check COtrip ->Vehicle guide
Register a vehicle
Sort out county registration, emissions, ownership tax, plates, and the parks pass line.
Read the guide ->More road help
Cars and driving notes
Browse short Colorado notes on roads, vehicles, mountain travel, and local driving rules.
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