Aspen ===== Current Keywords: CONSIDERABLE, MODERATE, avalanche danger, cold front, cross loaded, cross loading, crossloaded, density, depth hoar, drifts, faceted, faceting, facets, high pressure, loose snow avalanches, ski cut, slabs, sluffs, weak layer, weak layers, wind loaded, wind loading, windloaded, windslabs, Mountain Weather and Avalanche Forecast for the Aspen Zone Forecast Issued on 12/29/2007 3:48:14 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) -3 to 2 10-15 -5 to 0 Wind Speed(mph) 15-25 15-25 G50 20-30 G70 Wind Direction NW W W Sky Cover Mostly Cloudy Overcast Overcast Snow(in) 3-6 2-5 3-6 Snowpack Discussion Observers in the Crystal River valley and Yule Creek areas spotted widespread loose snow avalanches. They ran in terrain generally 35 degrees and steeper, on all aspects. Most of the sluffs were too small to bury a person, but watch out for them around terrain traps and in exposed areas where the moving snow may knock you off your feet. Cold temperatures and light snow will increase the potential size of these sluffs on Sunday. Control work at the ski areas triggered a few small avalanches below treeline in areas where the snowpack has faceted into sugar. Moderate to strong winds out of the southwest, west, and northwest have created fresh drifts and windslabs near and above treeline. Areas of wind loading and cross loading can now be found on slopes facing north through east through south. On Friday near Marble Peak, observers found two layers of recent windslabs in the upper snowpack. The slabs were sandwiched between layers of low density snow, creating that ominous strong over weak layering. Control teams at the ski areas were able to trigger wind pockets with ski cuts. Any steep wind loaded or cross loaded slope near and above treeline should be treated with caution right now. Variable wind speeds and directions during this period mean that these slabs exist in pockets on many slopes. Conditions can change quite a bit over a short distance. Human triggered avalanches will be possible to probable in these areas. The cold temperatures have accelerated the growth of facets in the snowpack. Fragile depth hoar continues to grow near the ground, and the upper layers of the snowpack are faceting and loosing strength. The layers become weaker as the grains grow larger. In the diamond industry, they say "diamonds last forever." Like diamonds, facets can last the entire season and are persistently weak. The potential for full depth avalanches is slowly increasing as faceted snow grains are starting to replace the rounded ones we like so much. This is most evident in areas of the zone where the snowpack is shallower. Multiple weak layers in the snowpack and a high degree of variability from one slope to the next require a cautious approach to backcountry travel. Frequent snowpack, weather, and avalanche observations will help you sort out the current conditions. Avalanche Danger Near and above treeline the avalanche danger is CONSIDERABLE on steep windloaded or crossloaded slopes facing north, northeast, east, southeast, and south. The danger is MODERATE on other aspects above treeline. The avalanche danger is MODERATE on all aspects below treeline. Please send us a quick e-mail to caic@qwest.net with your avalanche, snowpack, or weather observations from this area or any other. Those observations are very valuable to our forecasts. Front Range =========== Current Keywords: CONSIDERABLE, LOW, MODERATE, avalanche danger, cold front, depth hoar, drifts, faceted, faceting, high pressure, human triggered, human triggered avalanches, slab, slabs, weak layers, wind loading, wind slabs, windloading, windslabs, Mountain Weather and Avalanche Forecast for the Front Range Zone Forecast Issued on 12/29/2007 3:45:39 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) -5 to 0 10-15 -5 to 0 Wind Speed(mph) 20-30 G60 20-30 G60 20-30 G80 Wind Direction NW NW W Sky Cover Mostly Cloudy Overcast Overcast Snow(in) 1-4 3-6 2-5 Snowpack Discussion One new avalanche to report. Friday afternoon a skier triggered an avalanche in Nitro Chute, just northwest of Berthoud Pass. It is a steep northeast aspect near treeline, and the avalanche broke to the ground, about 2 feet deep and 50 feet wide. The avalanche failed in depth hoar, and was probably triggered from a shallow area that has faceted and lost strength in the recent cold temperatures. In the Vail Summit zone, skiers have triggered a couple other slides, and found increasingly sensitive windslabs. Strong winds out of the southwest, west, and northwest have created fresh drifts and windslabs near and above treeline. You will find a mix bag of soft to ugly windslabs, especially on steep easterly aspects. The slabs will be getting deeper and more extensive as bits of snow and strong winds continue. Areas of wind loading and cross loading can now be found on slopes facing north through east through south. Observers report extremely variable conditions above treeline with some spots scoured down to the tundra and adjacent spots loaded with thick wind slabs. . These slabs will be getting deeper and more as bits of snow and very strong winds continue. The cold temperatures have really put the faceting process in warp speed - a process that is progressively weakening the snowpack. Fragile depth hoar continues to grow near the ground, and the upper layers of the snowpack are faceting and loosing strength too. The layers become weaker as the grains grow larger. The potential for full depth avalanches is slowly increasing. The most suspect slopes continue to be north through east where the snowpack is most complicated with a combination of new snow, new and old wind slabs, and a weak, faceted base layer. Human triggered slides remain probable on north through east aspects with windloading. So the picture is growing windslabs sitting on weakening snow sitting above a growing deep slab instability issue. If you dig below the surface it will resemble a sugar factory. Multiple weak layers in the snowpack and a high degree of variability from one slope to the next require a cautious approach to backcountry travel. Get out there, but as always use good route finding skills and smart backcountry protocols. Avalanche Danger The avalanche danger is CONSIDERABLE on north, northeast, east, and southeast aspects near and above treeline. Human triggered avalanches are probable on steep slopes with windslabs, drifts, or pillows. Winds have worked the snowpack over, leaving plenty of scoured, bare ground adjacent to the heavily loaded slopes. On northwest, west, southwest, and south aspects near and above treeline the danger is MODERATE. Below treeline the danger is MODERATE on north, northeast, east, and southeast aspects and LOW on other aspects. Grand Mesa ========== Current Keywords: MODERATE, avalanche danger, cold front, drifting, faceted, high pressure, slabs, surface hoar, weak layers, whumpfing, windloading, windslabs, Mountain Weather and Avalanche Forecast for the Grand Mesa Zone Forecast Issued on 12/29/2007 3:50:02 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) 0-5 15-20 -3 to 2 Wind Speed(mph) 10-20 10-20 G30 10-20 G40 Wind Direction W NW W Sky Cover Mostly Cloudy Overcast Mostly Cloudy Snow(in) 1-4 0-3 0-3 Snowpack Discussion Winds have picked up across the Mesa. Recent snow is blowing and drifting, creating soft slabs more than a foot thick. An observer found a buried surface hoar layer about 8-12" underneath the recent storm snow. He was surprised to find no failures on this layer with column tests in several hasty pits. Nonetheless, he remained quite concerned about this layer and said that he would not trust it. You need to approach steep slopes with caution and watch for signs of instability such as avalanches, cracking in the snow, or whumpfing sounds. Avalanche Danger There are pockets of CONSDIERABLE avalanche danger in the Grand Mesa zone, on steep northwest, north, northeast, east, and southeast aspects with recent windloading. You will find unstable windslabs sitting on top of weak layers. The most problematic areas are probably steep slopes that have surface hoar or weak faceted snow under new snow. The danger is MODERATE on other aspects. If you have any observations or data to share, please send them to [57]caic@qwest.net. San Juan North ============== Current Keywords: LOW, MODERATE, avalanche danger, cold front, collapsing,, cross-loaded, crusts, density, depth hoar, drifted, faceted, faceting, facets, high pressure, human triggered, slab, slabs, windloaded, Mountain Weather and Avalanche Forecast for the Northern San Juan Mountain Zone Forecast Issued on 12/29/2007 3:50:39 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) 0-5 13-18 -2 to 3 Wind Speed(mph) 15-25 15-25 G40 15-25 G50 Wind Direction NW W W Sky Cover Mostly Cloudy Mostly Cloudy Mostly Cloudy Snow(in) 0-3 0-2 0-3 Snowpack Discussion Friday's blue-sky morning allowed for great visibility and, except for a few small loose sloughs out of steep terrain, observers spotted little new avalanche activity. There was a good sized slide spotted on a south to southeast aspect near Ophir (SS-N-R2D2.5-O). The slide started around 12,700' and ran aobut 800 vertical feet. Recent snows have been low-density, so while the inches have been adding up, the weight to the snowpack has not tilted the hazard scale. Observers are consistently noting that the lower portion of the snowpack, which developed during the warm storms in early December, is strong, particularly at higher elevations. Weak, faceted snow and developed depth hoar can be found below this slab, mostly on high northerly slopes, but the fat base layers of advanced depth hoar are not as pervasive this season as we are accustomed to. Observers have even noted slow strengthening of these faceted base layers in certain areas, resulting from the thick, warm early-December slab "capping" the relatively weak snow below. At lower elevations, however, the thinner snowpack is beginning to show signs of weakening. Observers are noting more and more "hollow" areas, generally around rocks and vegetation, that are the result of faceting with recent cold temperatures. Recent periods of wind, cold temperatures and new snow, have increased the complexity of the upper snowpack. Layers of storm snow, wind slabs, sun crusts and buried facets all demand that we pay close attention to the upper portion of the snowpack. Over the weekend shots of snow and increasing winds will form yet another layer of slabs to the stack. Backcountry travelers are continuing to get out in force and fresh tracks in the "bread and butter" areas are becoming more scarce. If you are starting to push out into steeper and more exposed terrain, remember that human triggered slides remain possible, particularly within these upper snowpack layers. For now, as you travel through the backcountry, continue to monitor for signs of instability in the upper snowpack like cracking, collapsing, or recent slide activity. Respect the snowpack and do not take it for granted! Get out there, but as always use good route finding skills and smart backcountry protocol. Avalanche Danger The avalanche danger for the Northern San Juan is MODERATE on all slopes that are near and above treeline. Some areas are scoured from recent winds, but next to them you will find windloaded slopes. Unstable slabs are possible on steep drifted and cross-loaded slopes. Below treeline the danger is MODERATE on west through north to east aspects, and LOW on southeast, south, and southwest aspects. San Juan South ============== Current Keywords: LOW, MODERATE, avalanche danger, cold front, density, drifting, faceting, facets, high pressure, human triggered, slabs, surface hoar, weak layers, windloaded, windloading, windslabs, Mountain Weather and Avalanche Forecast for the Southern San Juan Mountain Zone Forecast Issued on 12/29/2007 3:51:09 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) 0-5 15-20 5-10 Wind Speed(mph) 10-20 15-25 15-25 G40 Wind Direction SW SW W Sky Cover Mostly Cloudy Mostly Cloudy Mostly Cloudy Snow(in) 0-2 0-3 0-2 Snowpack Discussion There are no reports of recent avalanche activity. An observer on Wolf Creek Pass described the bottom portion of the snowpack as bomber and the conditions great. The upper snowpack is where our avalanche concerns are. There has been some snow drifting, blowing, and loading above treeline. The winds, in combination with low density snow and faceting driven by the cold temperatures, have created a variety of layers in the upper snowpack. These include some buried weak layers like surface hoar and near surface facets. So far they have not been much of a problem. This weekend, though, windloading will increase the load on slopes above treeline, making steep windloaded slopes more problematic. Human triggered slides remain possible near and above treeline on steep slopes with windloaded slabs. Do not wander unawares onto steep slopes with fat wind pillows, hard windslabs, or hollow, drum-like snow. Avalanche Danger The avalanche danger is MODERATE on all aspects near and above treeline. Unstable slabs are possible on steep, windloaded terrain. Below treeline the danger is LOW. Sangre de Christo ================= Current Keywords: avalanche danger, cold front, crossloaded, drift, high pressure, slab, slabs, wind slabs, Mountain Weather and Avalanche Forecast for the Sangre De Cristo Zone Forecast Issued on 12/29/2007 3:51:35 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) 0-5 15-20 -5 to 0 Wind Speed(mph) 15-25 G50 30-40 G70 20-30 G60 Wind Direction W W W Sky Cover Mostly Cloudy Mostly Cloudy Partly Cloudy Snow(in) 0 0 0 Snowpack Discussion We have received no observations from the Sangre zone. The Sangres are missing out on the light snow falling elsewhere in the state, and getting more than their fair share of winds. Westerly winds are strong, so any snow left on westerly aspects near and above treeline is going to be scoured. The winds will deposit and drift snow low onto northeast, east, and southeast slopes. Gullies and terrain features on other aspects will be crossloaded. You should watch for fresh wind pillows and slabs on steep slopes. You should also be aware of the possibilities for deep slab instabilities on N-NE-E aspects. A combination of fresh wind pillows, older wind slabs, and a weak base layer could avalanche large with a sufficient trigger. You should constantly evaluate the snowpack for changing conditions. Avalanche Danger We have insufficient data to rate the avalanche danger in the Sangre de Cristo Zone. Please send observations from this or any other zone to [57]caic@qwest.net Sawatch ======= Current Keywords: CONSIDERABLE, LOW, MODERATE, avalanche danger, cold front, collapsing , cross load, cross-loading, density, depth hoar, drifting, faceted, faceting, facets, high pressure, sastrugi, slabs, surface hoar, windslabs, Mountain Weather and Avalanche Forecast for the Sawatch Range Zone Forecast Issued on 12/29/2007 3:52:08 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) 0-5 13-18 -5 to 0 Wind Speed(mph) 20-30 G50 20-30 G50 20-30 G80 Wind Direction W W W Sky Cover Partly Cloudy Mostly Cloudy Partly Cloudy Snow(in) 1-4 2-5 1-4 Snowpack Discussion Since Thursday, a few inches of light snow have fallen each day. It looks like the pattern will continue through Monday. Winds have been from the southwest, west, and northwest, and will just increase in speed on Sunday. The winds and low density snow have and will continue to form slabs on northeast through southeast aspects, and cross load terrain features on north and south to southwest aspects. Winds scoured some spots down to the tundra, and loaded adjacent spots with thick windslabs. The slabs are sitting above either low density snow or small faceted grains and are not bonding well. There older slabs, too, on most aspects above treeline. The cold temperatures have accelerated the growth of facets in the snowpack. Fragile depth hoar continues to grow near the ground, and the upper layers of the snowpack are faceting and loosing strength. The layers become weaker as the grains grow larger. In the diamond industry, they say "diamonds last forever." Like diamonds, facets can last the entire season and are persistently weak. The potential for full depth avalanches is slowly increasing. There are also some pockets of buried surface hoar. You will need to poke around in the snowpack and see if the surface hoar is present on slopes you plan to ride. Recent windslabs on a weakening snowpack does not make for a good combination. You will find pockets of unstable windslabs on most aspects near and above treeline. Watch for clues like wind etching, sastrugi, hollow drum-like snow, and thick wind pillows. Cracking and collapsing are good indicators of unstable snow. Avalanche Danger The avalanche danger is MODERATE with pockets of CONSIDERABLE on northwest, north, northeast, east, southeast and south aspects near and above treeline. The danger is MODERATE on other aspects near and above treeline. Be especially cautious on steep slopes with cross-loading or drifting. Below treeline the danger is LOW on all aspects. Steamboat ========= Current Keywords: LOW, MODERATE, avalanche danger, cold front, cross loaded, facets, high pressure, human triggered, lee , slabs, wind slabs, Mountain Weather and Avalanche Forecast for the Steamboat and Parks Range Zone Forecast Issued on 12/29/2007 3:28:20 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) -3 to 0 8-13 -3 to 2 Wind Speed(mph) 15-25 15-25 G40 15-25 50 Wind Direction W W W Sky Cover Mostly Cloudy Overcast Overcast Snow(in) 4-8 3-6 3-6 Snowpack Discussion No avalanches have been reported recently. With careful route selection, a number of lines have been ridden and folks are venturing into steeper terrain. Near the ski area, one of our forecasters found "big strong slabs sitting on the ubiquitous weak facets on northerly aspects." The slabs, though, are strong enough that the facets are hard to trigger. The potential for full depth avalanches remains, but it is getting more and more unlikely. New snow will add up and become the next avalanche problem. With increasing winds you can expect to find some new, reactive soft slabs forming on northeast through southeast aspects. Fresh wind pillows on top of the snowpack should keep you on your toes. You will find pockets of unstable slabs on north, northeast, east, southeast, and south aspects near and above treeline. Do not jump blindly onto steep slopes. Spend a bit of time checking the layering, and how well those old slabs want to stick together. For now, the most suspect slopes are on lee and cross loaded aspects near and above treeline where new snow and older wind slabs have combined to create areas of instability. Avalanche Danger The avalanche danger in the Steamboat zone is MODERATE on all northwest, north, northeast, east, and southeast aspects at all elevations. Human triggered slides are possible on steep slopes with fresh wind pillows. The danger is LOW on other aspects. If you have any observations or data to share, please send them to [57]caic@qwest.net. Vail ==== Current Keywords: CONSIDERABLE, LOW, MODERATE, avalanche danger, cold front, cornice, creep, cross loading, drifts, faceted, faceting, high pressure, human triggered avalanches, natural, shears, slab, start zones, sugar snow, weak layers, wind loading, windslabs, Mountain Weather and Avalanche Forecast for the Vail and Summit County Zone Forecast Issued on 12/29/2007 3:47:19 PM Forecaster: Spencer Logan Weather Synopsis Clouds will fill in this afternoon as a warmer, moist airmass moves over. Snow will intensify late this afternoon, with most of the accumulation coming before midnight. More snow tomorrow, with most coming between noon and midnight as a cold front sags south from Wyoming. A jet streak moves over the northern mountains Sunday afternoon, and one model brings the 200 mph core right over the Eisenhower Tunnel. It is going to be windy in the northern and central mountains, and the dynamics could help wring some more snow out of the clouds. This northwest flow favors the Park, Gore, Flattops, and Elks. The northwest San Juans can do well on this northwesterly flow, too, but it looks like the range is on the edge of the moisture stream. If the weather pattern shifts a little south, the North San Juan zone will see heavier than forecast snowfall. A high pressure ridge builds Tuesday, and promises clear skies for the rest of the week. Weather Saturday Night Sunday Sunday Night Temperature(°F) -5 to 0 10-15 -5 to 0 Wind Speed(mph) 20-30 G50 20-30 G50 20-30 G70 Wind Direction NW NW W Sky Cover Mostly Cloudy Overcast Decreasing Snow(in) 2-5 3-6 1-4 Snowpack Discussion Some recent avalanche activity to report. On Friday afternoon, a skier triggered a soft slab on an east aspect, slightly above tree line, in the East Vail backcountry. The skiers triggered the avalanche from above and watched it run for close to 300 vertical feet. Observers spotted a natural had slab avalanche in the southern Tenmile range, on an east aspect above treeline. Strong winds out of the southwest, west, and northwest have created fresh drifts and windslabs near and above treeline. You will find a mix bag of windslabs, especially on steep easterly aspects. The slabs will be getting deeper and more extensive as bits of snow and strong winds continue. Areas of wind loading and cross loading can now be found on slopes facing north through east through south. Observers reported 60 foot long cracks shooting through 2 foot deep windslabs on northerly aspects. On easterly aspects, they got some windslabs to avalanche by trundling cornice chunks. The chunks triggered slides as they tumbled low into the start zones. The cold temperatures have really put the faceting process in warp speed - a process that is progressively weakening the snowpack. At and below tree line the snow pack is almost entirely faceted from the surface to the ground. You can hear the grains squeak under your feet. If you poke around in the snow you will find two main issues in the older snow. The first is in the upper half of the snowpack where a grain size difference exists from one layer of sugar snow to the next. You will find easy, clean shears when you test it. The second is the growing concern of larger faceted grains near the ground. The layer becomes weaker as the grains grow larger. The potential for full depth avalanches is creeping back into the picture. A small avalanche can ruin your day, so think of what a large one could do. So the picture is growing windslabs sitting on weakening snow sitting above a growing deep slab instability issue. If you dig below the surface it will resemble a sugar factory. Multiple weak layers in the snowpack and a high degree of variability from one slope to the next require a cautious approach to backcountry travel. Get out there, but as always use good route finding skills and smart backcountry protocols. Avalanche Danger The avalanche danger for the Vail-Summit zone CONSIDERABLE on north, northeast, east, south, and southeast aspects near and above treeline. Human triggered avalanches are probable on steep slopes with recent windslabs. On northwest, west, and southwest aspects near and above treeline the danger is MODERATE. Below treeline the danger is MODERATE on north, northeast, east, south, and southeast aspects and LOW on other aspects.