Chinook and Cayuse Passes

Last update: Thursday, April 29, 2021
The plows and blowers are into the deepest snow and the biggest avalanche risk. The avalanche crew has been blasting away at the snowpack with avalanches big enough to bury the road. View photos of our progress on Flickr and follow @SnoqualmiePass on Twitter.  

From April 26
The avalanche crew cleared a couple of the main avalanche paths. Temperatures continue to warm up, however, Chinook Pass received some snow over the weekend. More maintenance and avalanche control work planned this week. No exact reopening date set yet for SR 410/Chinook Pass, but so far, crews are on track for Memorial Day weekend.

From April 16:
Snow plows are about one mile east of the summit. There's lots of avalanche control work that needs to be done before they can move forward safely. Avalanche debris is deeper than previous years. Temperatures are warming up this weekend so we anticipate lots of avalanche activity. Currently, there is 175 inches of snow at the SR 410/Chinook summit. 

From April 12:
Crews made a lot of progress on SR 410/Chinook last week clearing about three miles. Right now, they are two miles east of the summit and had to take a short break for safety as our avalanche crew went back to I-90/Snoqualmie Pass during the recent snow event.

From April 2:
Crews started clearing SR 410/Chinook Pass on Monday, March 29. SR 123/Cayuse Pass clearing efforts began early March. Every year, our goal is to reopen both passes by Memorial Day weekend. View historic reopening and closing dates.  

State Route 410 Chinook Pass and SR 123 Cayuse Pass are closed to vehicle traffic for the season.  

Chinook Pass (elev. 5,430 feet) is closed between Crystal Mountain Boulevard, about 12 miles northwest of the summit, and Morse Creek, 5 miles east of the summit. Cayuse Pass (elev. 4,675 feet) is closed within the boundaries of Mount Rainier National Park between Crystal Mountain Boulevard and the park arch at milepost 2.5 at the southern park boundary. These passes typically close sometime in mid-November each year due to avalanche danger, poor road conditions, lack of emergency services in close proximity and limited snow storage.

Visit the Mount Rainier National Park’s road status webpage and follow @MountRainierNPS on Twitter for updates about other roads within Mount Rainier National Park.

Tools to keep travelers connected

Drivers can now sign up for email alerts for SR 410/Chinook Pass and SR 123/Cayuse Pass. After entering their email address, subscribers should check the box for "Mount Rainier Area State Highway News" under the "Mountain Pass Conditions" section of the page.

Seasonal Closure Information

Chinook and Cayuse passes provide travelers two scenic routes through the Cascade Mountain range in Washington that take visitors through Mount Rainier National Park.

Chinook Pass, the east entrance to the park, is located three miles east of Cayuse Pass and 51 miles west of Naches on SR 410. It has an elevation of 5,430 feet.

Cayuse Pass is located at the junction of SR 123 and SR 410 which is approximately 21 miles east of Greenwater on SR 410 and 16 miles north of US 12. It has an elevation of 4,675 feet.

Why do the passes open and close seasonally?

Chinook and Cayuse passes close every fall due to avalanche danger, poor road conditions, lack of snow storage and no emergency response services within close proximity. All of these concerns make travel hazardous for the public as well as maintenance crews. The safest approach to managing these passes is to simply close the roads once winter conditions warrant the need. In addition, both passes rely on the National Park Service (NPS) emergency and summer seasonal staff to monitor the roadways. There is a shortage of staffing during the winter months.

Chinook and Cayuse passes typically close sometime in mid-November each year. The target date for reopening in the spring is Memorial Day weekend, although that depends on the amount of snow that falls during the winter months, as well as spring weather conditions.Chinook Pass Summit

During seasonal closures, Crystal Mountain can be accessed from Enumclaw on SR 410, but not from the east side of Chinook Pass. White Pass can be accessed from US 12, but not SR 123.

View a table of opening and closing dates since 1935

Chinook and Cayuse passes by-the-numbers

On average maintenance crews clear over 30 miles of snow on the two passes. Crews use bulldozers and snow blowers to remove snow 30 feet deep or more from the roadways. It takes approximately 3,000 crew hours over a four to six-week period to clear more than two billion cubic yards of snow in order to reopen Chinook and Cayuse passes each year.

To help reduce the danger of hazardous avalanches during the clearing process, trained crews knock down snow using up to 1,600 pounds of explosives. Avalanche control with the use of explosives is rarely performed in Mount Rainier National Park to avoid damage to natural resources, historic roads and to protect the federally designated wilderness.

Working Together

Opening and closing Chinook and Cayuse passes requires coordination between WSDOT, NPS and the Washington State Patrol. The NPS hires WSDOT to clear the snow within the park boundary. WSDOT also repairs the highways and posts signage. The NPS patrols the state highways inside the park, provides staffing and other recreational amenities. WSP patrols the highways outside the park.

Safety is our number one priority and the passes do not reopen for the season until WSDOT, NPS and WSP agree to do so.

Clearing Cayuse Pass

Tools to keep travelers connected

Drivers can now sign up for email alerts for SR 410/Chinook Pass and SR 123/Cayuse Pass. After entering their email address, subscribers should check the box for "Mount Rainier Area State Highway News" under the "Mountain Pass Conditions" section of the page.

Current weather and highway conditions are posted on our mountain passes webpage.


​How can I get more information?


Summer Derrey
WSDOT Communications/Chinook Pass

Northwest Region Public Affairs
WSDOT Communications/Cayuse Pass

National Park Service

Tracy Swartout
Deputy Superintendent/Mount Rainier National Park