A wildfire that started around 10 a.m. on Wednesday, September 16, in the Truckee River Canyon near Floriston, California, closed westbound Interstate 80 at the Nevada state line within hours. By mid-afternoon CAL FIRE put the Floriston Fire at about 300 acres and 5 percent contained, Nevada County had evacuation warnings in place, and the cause was under investigation.
That stretch of I-80, about nine miles northeast of Truckee, is the main road between Reno and Truckee, and part of the main route from Reno over Donner Summit to Sacramento and the Bay Area. If you are driving it this week, or planning a Sierra trip before the snow arrives, here is how to travel around a fire without becoming part of the problem.
What we know so far
These details were current on Wednesday afternoon, September 16. Fires move faster than articles, so treat them as background and check the live sources in the next section before you set off.
- Location: near I-80 and Floriston, on the California side of the state line, about nine miles northeast of Truckee.
- Size: about 300 acres and 5% contained as of mid-afternoon, according to CAL FIRE, after an initial report of 20 acres.
- Roads: westbound I-80 closed at the Nevada state line, with no estimated reopening time from the California Highway Patrol.
- Evacuations: Nevada County issued warnings for zones NCO-379, NCO-E105 and NCO-E106. A mandatory order for the area west of I-80 to Boca Road was issued shortly before 1 p.m. and downgraded back to a warning about 40 minutes later.
- Air quality: Northern Nevada Public Health warned that air in the Verdi and North Valleys areas could reach levels that are unhealthy for sensitive groups, or unhealthy for everyone.
- Cause: under investigation.
Where to check before you drive
Do not rely on a navigation app alone. Apps can lag behind a new closure, and they do not show evacuation zones or smoke. These are the sources the agencies themselves update:
- Caltrans QuickMap: live closures, incidents and chain controls on California highways, including I-80 up to the state line.
- NV Roads: the Nevada Department of Transportation’s road conditions map for the Nevada side, from Verdi into Reno.
- CAL FIRE incidents: acreage, containment and official updates on the fire.
- Ready Nevada County: evacuation orders and warnings for the county where the fire is burning.
- AirNow Fire and Smoke Map: current smoke and air quality readings, useful for deciding whether a hike or a day by the lake still makes sense.
Check them again before the return trip. A road that is open when you leave in the morning can be closed by the afternoon, which is exactly how Wednesday went.
Detours that actually work
The Sierra Nevada has only a handful of highway crossings, so a closed I-80 means a long way around. The right detour depends on where you are headed.
Reno to Truckee or the north shore of Lake Tahoe
Take the Mount Rose Highway (Nevada State Route 431) from south Reno over the mountain to Incline Village. From there, follow State Route 28 along the lake to Kings Beach and turn north on State Route 267 to Truckee. It is a steep, winding mountain road rather than an interstate, so allow extra time, but it keeps you well south of the canyon.
Reno to Sacramento and the Bay Area
The usual alternative is US Highway 50. Head south to Carson City on Interstate 580, then take US 50 west past the south end of Lake Tahoe and over Echo Summit toward Sacramento. It adds a lot of time to the trip, but it is a proper trans-Sierra route.
A northern option is US 395 north from Reno to Hallelujah Junction, then State Route 70 west through the Feather River Canyon. It makes the most sense if you are heading for the northern Sacramento Valley rather than the Bay Area.
Before committing to either, check the whole route on QuickMap. Detours carry far more traffic than usual when an interstate closes, and fire season in the Sierra is rarely down to a single fire.
By train
Amtrak’s California Zephyr runs through the same Truckee River Canyon between Reno and Truckee. If you are booked on it through the area, check Amtrak’s service alerts rather than assuming the rail line is unaffected.
Driving the Sierra during fire season
The Floriston Fire is a reminder that September is still fire season in the Sierra, even when the nights are already cold. A few habits make a real difference:
- Keep the tank at least half full. Detours are long, and a sudden closure can leave you sitting in stopped traffic.
- Carry water, snacks and any medication you need for a longer day than you planned.
- Do not pull over to photograph a fire. Parked cars on the shoulder get in the way of fire engines and of residents who are evacuating.
- In heavy smoke, switch the car’s ventilation to recirculate and drive with your headlights on.
- Look for local emergency alerts. Visitors are not automatically on county alert lists, so check whether the county you are staying in lets you sign up.
- Take evacuation warnings seriously even if you are only passing through. A warning means conditions can change quickly. It is not the moment to check in to a cabin inside the zone.
Planning a Tahoe or Reno trip in the coming weeks
News about a fire can make a whole region sound off limits when the impact is local. A closure on one stretch of interstate does not close Reno, Truckee or Lake Tahoe. What it does mean is building slack into your plans: a flexible day, a refundable night, and a route you check again on the morning you leave.
The same thinking applies whenever the drive is the riskiest part of a trip. Our guide to what Black Rock City asks of you before Burning Man makes the case for treating the road in and out as part of the journey rather than a transfer. And if you are already looking past fire season toward the first snow, our winter 2026-2027 snow forecast breaks down what the long-range outlooks say for ski trips.
