Ogden Avalanche Advisory

Forecaster: Bruce Tremper


Danger by aspect and elevation on slopes approaching 35° or steeper.
(click HERE for tomorrow's danger rating)

Danger Rose Tutorial

Terrain I continue to avoid:

* West, northwest, north, northeast and east facing slopes steeper than about 32 degrees.

* Any steep slope with recent wind deposits.

Usually-safe terrain:

* All slopes less than 30 degrees and not locally connected to steeper terrain

Overall, the avalanche danger remains Level 3 (Orange or Considerable) because of very tricky, low-probability, high-consequence avalanche danger.


4-5 inches of very low density (5%) new snow fell in Little Cottonwood Canyon with about 3 inches elsewhere. Skies cleared overnight with just a few scattered clouds coming in from the east on a wrap-around flow. Temperatures were in the single digits the morning with a light breeze from the east.


There was no significant avalanche activity reported from the backcountry yesterday with the exception of some relatively minor, soft, wind slabs along the ridges and some sluffing on steep, south facing slopes on the sun crust.


      Over the next 24 hours.

We have what I call a "Dirty Harry" snowpack. There may or may not be one round left in the chamber but if you guess wrong, it's a VERYbig bullet. So how lucky do you feel today?

Our avalanche danger ratings depend on both probability and consequences. Our old nemesis, the faceted snow at the bottom of the snowpack (depth hoar) continues to SLOWLY gain strength, so the probability continues to go down but the consequences remain the same--namely that the entire mountainside will rip out several feet deep. The trouble is that it's nearly impossible--even for pros--to tell which slopes will slide and which will not. Snowpit tests work very poorly for deep slabs and the snowpack structure is extremely variable from place to place and evidence of avalanches during the last storm are nearly invisible now.

If you're interested in the geekier side of deep slabs, you should check out several entries in our Current Conditions section. First, Drew Hardesty was getting identical stability test results on both slopes that slid during the last storm and ones that did not. Second, Trent Meisenheimer videoed some interesting results with a Propagation Saw Test. Third, if you have an extra 15 minutes and want to get deep into the weeds, I posted a YouTube screen capture of PowerPoint tutorial on deep slabs and the basics of terrain management.

The bottom line is that the riding conditions are so good on slopes less than 30 degrees, there's no sense in playing Russian Roulette on the steeper terrain that faces the north half of the compass. South facing slopes are much safer but there are also more rocks.


      Over the next 24 hours.

With very fluffy new snow, it does not take much wind to blow it around. Yesterday, the winds blew from a variety of directions starting from the west and ending from the east. This created some localized, soft, wind slabs along the upper elevation ridges. People were able to easily crack some of these out yesterday. Winds continue to blow hard from the east in the Logan and Ogden area mountains so the wind slabs will be more dangerous than in the Salt Lake City area mountains.


We should have mostly clear skies today but with some wrap-around moisture still streaming in from the east, we may see some scattered clouds at times. Temperatures will remain cool with overnight lows in the single digits and daytime highs in the mid 20's. Winds will remain light and from the east.

Unfortunately, we don't see any significant snow in the forecast for at least a week--probably longer.


If you trigger an avalanche in the backcountry - especially if you are adjacent to a ski area – please call the following teams to alert them to the slide and whether anyone is missing or not. Rescue teams can be exposed to significant hazard when responding to avalanches, and do not want to do so when unneeded. Thanks.

Salt Lake – Alta Central (801-742-2033)

Ogden – Snowbasin Patrol Dispatch (801-620-1017)

Provo – Sundance Patrol Dispatch (801-223-4150)

Dawn Patrol Forecast Hotline, updated by 05:30: 888-999-4019 option 8.

Twitter Updates for your mobile phone http://utahavalanchecenter.org/twitter)

Daily observations are frequently posted by 10 pm each evening.

Subscribe to the daily avalanche advisory e-mail click HERE.

UDOT canyon closures UDOT at (801) 975-4838

Wasatch Powderbird Guides does daily updates about where they'll be operating on this blog http://powderbird.blogspot.com/ .

You have the opportunity to participate in the creation of our own community avalanche advisory by submitting avalanche and snow observations. You can also call us at 801-524-5304 or 800-662-4140, or email by clicking HERE

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We will update this forecast tomorrow morning. Thanks for calling.

This information does not apply to developed ski areas or highways where avalanche control is normally done.  This advisory is from the U.S.D.A. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.

This advisory provided by the USDA Forest Service, in partnership with:

The Friends of the Utah Avalanche Center, Utah Division of State Parks and Recreation, Utah Division of Emergency Management, Salt Lake County, Salt Lake Unified Fire Authority and the friends of the La Sal Avalanche Center. See our Sponsors Page for a complete list.