Wasatch Cache and Uinta National Forests

In partnership with: Forest Service Utah Avalanche Center, The Friends of the Utah Avalanche Center and Utah State Parks.

Avalanche advisory

Sunday, March 16, 2003

Good Morning. This is Craig Gordon with the Forest Service Utah Avalanche Center with your avalanche and mountain weather advisory for the western Uinta Mountains including but not limited to the terrain surrounding Chalk Creek, Smith-Moorehouse, the Mirror Lake Highway, and Woodland. Recent observations near Daniels and on the Evanston side of the range indicate similar snowpack conditions.

This advisory is made possible through a generous grant provided by Utah State Parks and will be available for the rest of the winter on weekends and holidays.

Today is Sunday, March 16, 2003, and it’s 7:30 in the morning.

Current Conditions:

Overnight snowfall totals look to be in the 4”-6” range in the upper elevation terrain. Temperatures began cooling around midnight and as of 6:00 it’s near 20 degrees at 10,000’. Winds are beginning to relax a bit and are out of the southwest at speeds of 10-20 mph along the ridges. The old snow surface is a mix of supportable crusts and old tracks in the more popular areas, but off the beaten track good powder riding and turning conditions can be found on sheltered, shady slopes.

Avalanche Conditions:

The weak facets that have plagued our snowpack all year continue to be an active layer, especially in rocky terrain where snow depths remain shallow. Yesterday a snowmobiler was able to trigger an avalanche on a steep slope with a relatively shallow underlying snowpack in ‘The Super Bowl’. The avalanche was 2’ deep, 30-40 yards wide, and ran for about 500 vertical feet. Reports are that the rider came out unscathed.

While the snowpack has gained quite a bit of strength this past week the weakest snow I’ve seen continues to be in steep, rocky terrain. It looks like we’re due for a decent shot of snow over the next couple of days and the track record of our consistently weak snowpack reveals that each time it receives a substantial load, we see avalanches.

Today we have a couple of factors to think about. First off, the winds were strong as this little system moved over the region and newly formed wind drifts will be sensitive to the weight of a backcountry traveler. These will most likely be confined to upper elevation, leeward terrain. There are plenty of hard, slick bed surfaces for these soft slab avalanches to run on and they could pack enough punch to knock you off your machine or skis and take you for a rapid ride down slope.

Secondly, our problem child, the weak facets near the ground, continues to haunt us especially on steep, upper elevation slopes where the snowpack is thin and weak. While avalanches failing on old snow are becoming more pockety and isolated in nature, the avalanche triggered yesterday proves that this layer still reacts to the additional weight of a person.

Bottom Line:

The avalanche danger is MODERATE today on all steep slopes with recent deposits of wind drifted snow. Human triggered avalanches are possible.

There is also a MODERATE or localized danger of triggering a deeper avalanche on weak snow near the ground on steep northwest through east facing slopes. Human triggered avalanches are possible especially on rocky slopes with a weak, shallow snowpack.

Mountain Weather:

Snowfall rates will begin to taper off later today as the Pacific system moves to the east of the region. We might be able to squeak another 3”-6” of snow out of this storm before it’s all said and done. Temperatures will be cool today with highs at 10,000’ in the low 20’s and at 8,000’ near 30 degrees. Overnight lows will be near 20 degrees. Winds should turn around to the northwest this morning and will remain in the 10-20 mph range along the ridges. For the upcoming week it looks like we’ll remain in a cold, unsettled pattern through about Friday with a chance of snow each day.

General Information:

If you’re getting out and about please let us know what you’re seeing, especially if you see or trigger an avalanche. Call 1-800-662-4140, or 801-231-2170, or email to uac@avalanche.org or fax to 801-524-6301. Your observations could help to save someone’s life. I’ve received some great observations this past week and thanks to those of you who called in with timely snowpack and avalanche information. Please keep them coming!

We will be offering free snowmobile specific avalanche education this year. To schedule a talk and or a field day please call 801-231-2170.

The information in this advisory is from the U.S. Forest Service, which is solely responsible for its content.

This advisory describes general avalanche conditions and local variations always occur.

I will update this advisory by 7:30 a.m. on Saturday, March 22, 2003.

Thanks for calling!