New guest blog by Tom Diegel - The Little Things (that might keep you alive) - Part I

I want to thank Dr. Cianna Wyshnytzky and the students in her "Glacial Field Methods" class at Westminster College who on Thursday evening helped me draft today's advisory.

There is a temperature inversion in the mountains this morning, with low elevation trail heads in the low teens, and in the mid 20's at mid and upper elevations.

Winds are out of the west/southwest and are light at low elevations. They are blowing in the low teens at mid and upper elevations, with gusts in the 20's mph at the upper elevations.

Slopes facing east, south, and west will be crusted this morning, and will soften and loosen with daytime warming. Mid and upper elevation northerly aspects will hold soft, dry snow, with wind-affected snow in the upper elevations.

Week in Review (Feb 24- Mar 2)

The snowfall from the 3-4' storm from the week of February 20 settled out by Saturday Feb 25 and treated backcountry skiers and riders with a weekend of deep, soft snow with generally stable conditions. Many steep lines were skied with the only concern of sluffing in the loose, dry snow.

By later Sunday afternoon, wind speeds increased ahead of yet another storm that initially arrived on a southwest flow, but switched to northwest later on Monday. Heavy snowfall during the day on Monday led to a natural cycle during periods of intense precipitation. Light snow continued overnight on Monday, with a weaker system later on Tuesday that added several more inches of snow.

Storm totals (and water equivalent) since Sunday evening included:

• Cottonwoods: 16 - 28" (1.15 - 1.7")
  
• Park City mountains: 19" (1.6")
  
• Ogden mountains: 17 - 28" (0.5 - 1.5")
  
• Provo mountains 10" (0.75")

Stability rapidly increased by Tuesday was well with most observers only noting loose sluffs in very steep terrain. West and northwest winds also began to increase later Tuesday and into Wednesday morning, with wind-affected and drifted snow in the mid and upper elevations. These drifts were sensitive earlier in the day on Wednesday, but had largely settled out and were mostly unreactive by Thursday. Warm temperatures and strong sun on Thursday created loose wet avalanche activity on east, south, and west aspects.

February totals from Alta Guard (courtesy of Mark Sauer) are 114" of snow with 9.0" of water. This exceeds the average of 81.4" and is the 8th snowiest February on record. Also of note, the seasonal snowfall at Alta Guard is currently 413" and is the first time it has topped 400" for a full season since 2010-11.

The most significant activity reported from Thursday was a natural cornice fall on Scott Hill along the Park City ridgeline (Photo @bayoudave)

This occurred on an east facing slope and was 400' wide with debris 10-15' in places. This avalanche took out some large trees, and stepped to the ground in places. (We will post a summary of this avalanche on the UAC website on Friday morning.)

Otherwise, widespread loose wet activity occurred on the sunny east through west aspects, beginning with southeast by about 10 am.

Today will be another warm one with 8000' temperatures forecasted to reach the upper 40's. At 10,000' temperatures will rise to just below freezing.

Clear skies to begin the day, with increasing high clouds later.

South and southwest winds will increase throughout the day, with averages in the 20's mph at 10,000', with gusts approaching 40 mph above 10,000'. Increasingly strong winds overnight and into Saturday. Saturday is looking warm and very windy. Fortunately a cloud front arrives Sunday with what is currently shaping up to be a decent snow producer overnight Sunday into Monday. It is a short-duration event which may limit snowfall totals.