Heavy snow threatens travel across Colorado's San Juan Mountains through Monday morning, with separate warnings for the eastern passes and the northwest and southwest ranges. Drivers planning a Sunday evening crossing face different start times, snowfall forecasts and end times depending on the pass.
The National Weather Service warnings cover terrain above 10,000 feet. A mountain town named in the forecast can receive different amounts on its lower-elevation streets.
Which warning covers your crossing
| Area and named passes | Snow forecast | Wind gusts | Warning window, Mountain Standard Time |
|---|---|---|---|
| Northwest and southwest San Juans, including Red Mountain, Molas, Coal Bank and Lizard Head passes | 12 to 18 inches, locally more | Up to 45 mph | In effect until noon Monday, November 2 |
| Eastern San Juans, including Wolf Creek and Cumbres passes | 8 to 14 inches | Up to 50 mph | 5 p.m. Sunday, November 1, through 11 a.m. Monday, November 2 |
The eastern warning's start is 4 p.m. Pacific Sunday. Its end is 10 a.m. Pacific Monday; the western warning ends an hour later. These are forecast accumulations, not measured snow depths or guaranteed road-reopening times.
Red Mountain Pass is on US 550. Wolf Creek Pass is on US 160, the highway that also serves Pagosa Springs. A trip involving both a valley approach and a high pass can encounter separate restrictions along the same route.
Traction equipment and chain requirements
Colorado can activate passenger-vehicle traction and chain requirements on any state highway. The Colorado Department of Transportation says motorists receive notice through highway signs, COtrip and traffic alerts. A weather warning by itself does not establish that a particular road has an active chain requirement.
For the traction requirement, CDOT's passenger guidance lists qualifying winter or all-weather tires, including mountain-snowflake or M+S markings, with at least 3/16 inch of tread, or chains or an approved alternative traction device. Its winter-driving FAQ also identifies all-wheel-drive and four-wheel-drive vehicles as compliant when all tires meet the 3/16-inch minimum.
CDOT cautions that AWD and four-wheel drive can help a vehicle accelerate on slick surfaces, while tires determine stopping and turning performance. It also advises fitting four winter tires: using only two can reduce steering response or put the vehicle at risk of fishtailing.
A passenger-vehicle chain requirement is stricter. Every vehicle must have chains or an approved alternative traction device. Do not treat an AWD badge as an exemption from that requirement.
CDOT lists a $100 noncompliance fine plus a $33 surcharge. Noncompliance that causes a travel-lane closure can bring a $500 fine and $157 surcharge, a combined $657.
For a rental vehicle, check the tire markings and tread as well as the rental company's permission to fit chains or an alternative device.
Road status and the Pagosa Springs restriction
COtrip is the state's road-condition service. Check the actual highway segment, its restrictions and the time attached to the report before leaving. The warning windows above describe weather risk; they do not confirm that US 550 or US 160 is open, closed or free of traction restrictions.
Pagosa Springs has a separate flood emergency. The town's Sunday notice restricts incoming US 160 traffic from 2 p.m. MST Sunday, or 1 p.m. Pacific. Evacuating traffic may leave. Residents in ordered river evacuation zones must leave immediately rather than wait for that road restriction. Our evacuation alert lists the shelter and affected rivers.
If avalanche-control work closes a highway, CDOT says it cannot estimate the duration because crews cannot predict how much snow will come down. For necessary travel, the weather service advises carrying a flashlight, food and water in case the vehicle is stranded.
