Aspen ===== Current Keywords: CONSIDERABLE, MODERATE, avalanche danger, creep, cross loaded, crown, crowns, dense, density, depth hoar, drifting, drifts, faceted, facets, high pressure, human triggered, natural avalanches, slab, slabs, test slopes, trough, weak layers, wind drifting, wind loaded, wind loading, wind slabs, windslabs, Mountain Weather and Avalanche Forecast for the Aspen Zone Forecast Issued on 1/1/2008 4:21:50 PM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Night Wednesday Wednesday Night Temperature(°F) -3 to 2 20-25 8-13 Wind Speed(mph) 10-20 10-20 10-20 Wind Direction W SW SW Sky Cover Clear Mostly Clear Partly Cloudy Snow(in) 0 0 0 Snowpack Discussion Observers around the Aspen Zone found the new windslabs slabs to be quite tender. Monday a skier triggered a soft slab avalanche just below Pearl Pass, on the Crested Butte side. It was on an ESE aspect at around 12,700 feet. The crown of the avalanche was up to two feet deep. Control work popped out soft slabs on Monday, too, on southeast aspects near treeline with crowns 1-2 feet deep. Observers found slabs up to 1ft thick on east aspects that were very reactive to a skier's weight. These slabs cracked and propagated up to 30 ft away on short test slopes. An observer in Ashcroft on Monday reported continuous loading on Green Mountain. The upper half of the snowpack there consisted of dense snow from recent wind deposition resting on a base of weak facets and depth hoar. The most concerning results in a test pit here were the basal weak layers. Strong and sustained winds out of the southwest, west, and northwest blasted the peaks at the end of the year. Terrain at and above treeline has seen significant effects from this wind, as well as some open and exposed areas below treeline. You will encounter widespread hard slabs, soft slabs, cross drifting, and plenty of "wind jacked" snow near and above treeline. Any steep wind loaded or cross loaded slope at any elevation should be treated with caution right now. In many areas these fresh drifts are resting on some older facets or lower density snow that made up the old surface. This strong over weak layering will make natural avalanches possible and human triggered ones probable. Lots of fresh wind slabs, multiple weak layers in the snowpack, and a high degree of variability from one slope to the next demand a cautious approach to backcountry travel. Expect to find very sensitive wind slabs and drifts in the backcountry. Avoid traveling on or below steep exposed slopes, particularly in near and above treeline areas. Light snow and intense wind loading added a lot of load to the snowpack. This means that the potential for full depth avalanches is slowly creeping back into the picture. These facets and depth hoar grains at the base of the snowpack will be the failure layer. A smaller slide that initiates in upper snowpack weaknesses may step down to these older layers. The most suspect areas for these full depth avalanches continues to be north through east facing slopes where the snowpack is most complicated with a combination of new snow, new and old wind slabs, and a weak, faceted base layer. Avalanche Danger The avalanche danger for the Aspen Zone is CONSIDERABLE on all aspects near and above treeline. Natural avalanches are possible and human triggered ones probable at these elevations. Steep slopes with fresh wind slabs should be avoided at this time. Below treeline in open or exposed areas, expect to find pockets of CONSIDERABLE danger on slopes 35 degrees and steeper that have seen recent wind drifting. In all other areas below treeline, danger is MODERATE. Clear skies will allow us a good look around the backcountry for the next couple days and we would love to know what you are seeing. Avalanche forecasting is a community effort. Help out your fellow backcountry travelers (and forecasters) by dropping us a quick e-mail at caic@qwest.net with any avalanche, snowpack, or weather observations you might have. Front Range =========== Current Keywords: CONSIDERABLE, Human triggered avalanches, MODERATE, collapsing , cross loaded, cross loading, drifted, drifting, drifts, high pressure, human triggered avalanches, natural, sastrugi, slabs, stabilize, sublimating, trough, wind slabs, windloaded, windslabs, windward, Mountain Weather and Avalanche Forecast for the Front Range Zone Forecast Issued on 1/1/2008 4:24:38 PM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Night Wednesday Wednesday Night Temperature(°F) -5 to 0 18-23 0-5 Wind Speed(mph) 15-25 10-20 10-20 Wind Direction WSW W SW Sky Cover Clear Mostly Clear Partly Cloudy Snow(in) 0 0 0 Snowpack Discussion There were several human triggered avalanches over the weekend, including two close calls. On Monday a snomobiler triggered a slide on Gravel Mountain, west of Grand Lake. The avalanche was triggered on an east aspect above treeline, and it completely buried the rider. Fast action on the part of a nearby group rescued the buried snowmobiler in a few minutes. Sunday, a skier triggered and was caught in an avalanche in the Indian Peaks near Eldora Ski Area. The avalanche was on a windloaded north northeast aspect at treeline. There were several skier triggered avalanches reported from the Berthoud Pass area on Friday and Saturday, again on windloaded north to east aspects. Control work brought down slides on north, east, southeast, and west aspects on Monday as well, some breaking 6 feet deep and running as far as 2,500 feet. Observers are still tallying up the natural activity, but southerly aspects above treeline were particularly active in the Vail Summit zone. It was difficult to measure snow with so much wind, but about 6 to 12 inches fell in the Front Range Zone during the last storm. Relentless westerly and northwesterly winds blasted the peaks, redistributing both new and existing snow and significantly altering the snow surface. Near and above treeline, most of the storm snow, and most of the old snow, was scoured off windward faces. The snow went somewhere--some sublimating off to Kansas--but most of the snow was drifted and loaded. You will encounter widespread hard slabs, cross drifting, and plenty of "wind jacked" sastrugi near and above treeline. Westerly aspects and wind exposed spots will be scoured to the ground. Expect to find areas of heavy loading and cross loading on slopes facing north through east through south. Some areas are stripped down to the rock, grass or early season snow while adjacent slopes lie plump with drifts. It will be easy to go from a relatively safe spot to a dangerous one with just a few steps. Keep in mind that wind slabs that formed over the weekend will not stabilize rapidly. Hard slabs are an insidious beast, allowing the unwary backcountry traveler to get far onto the slope before releasing with lightning speed. Watch for obvious signs of instability including recent avalanching, cracking, collapsing and stronger over weaker layering. Avoid traveling on or below steep exposed slopes above treeline. Avalanche Danger The danger is CONSIDERABLE on north, northeast, east, southeast and south aspects near and above treeline. Human triggered avalanches are probable on steep slopes with windslabs, drifts, or pillows. There are pockets of CONSIDERABLE danger on cross loaded terrain features on southwest, west and northwest aspects near and above treeline. Below treeline the danger is MODERATE. Human triggered avalanches are probable on steep wind-effected terrain below treeline. Grand Mesa ========== Current Keywords: avalanche danger, collapsing , drifted, drifts, high pressure, trough, weak layer, windslabs, Mountain Weather and Avalanche Forecast for the Grand Mesa Zone Forecast Issued on 1/1/2008 4:21:11 PM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Night Wednesday Wednesday Night Temperature(°F) 0-5 25-30 10-15 Wind Speed(mph) 0-10 5-15 5-15 Wind Direction SW SSW S Sky Cover Clear Mostly Clear Partly Cloudy Snow(in) 0 0 0 Snowpack Discussion Strong winds raked the whole state the end of last year and the Mesa was not spared. Winds were generally west and northwest and transported lots of snow. Look for areas of loaded and drifted snow on north through east to southeast aspects. The windslabs and drifts may not bond well with the old snow underneath, and could react to the weight of a backcountry traveler. Be aware of changes in the snow while you travel in the backcountry today. It may be easy to go from a relatively safe spot to a dangerous one with just a few steps. Watch for obvious signs of instability including recent avalanching, cracking, collapsing and hard over weak layering. Avoid traveling on or below steep exposed slopes today. Avalanche Danger We have insufficient data to rate the avalanche danger in the Grand Mesa Zone. Please send observations from this or any other zone to [57]caic@qwest.net San Juan North ============== Current Keywords: CONSIDERABLE, MODERATE, avalanche danger, crusts, drifted, drifting, drifts, faceted, facets, high pressure, naturals, paths, slab, slabs, starting zones, trough, weak layers, wind-loaded, windslabs, Mountain Weather and Avalanche Forecast for the Northern San Juan Mountain Zone Forecast Issued on 1/1/2008 4:20:52 PM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Night Wednesday Wednesday Night Temperature(°F) 0-5 22-27 10-15 Wind Speed(mph) 10-20 10-20 10-20 Wind Direction Var SSW SSW Sky Cover Partly Cloudy Partly Cloudy Mostly Cloudy Snow(in) 0 0 0 Snowpack Discussion Observers reported avalanches on most aspects from Sunday, Monday, and Tuesday. West, north, northeast, southeast, and south aspects all had activity. Sunday near Lake City a skier triggered an avalanche on a northeast slope just above treeline - the skier was not injured. Southerly aspects were particular active, with many naturals running from the combination of loading from "north winds and south crusts" underneath the slabs. Most of the activity was confined to the recent snow, only a foot or two deep. There was one exception, a 4 foot deep and 1000 foot wide monster that ran to the ground on a northeast aspect. It's a reminder that the snowpack still has weak facets at the bottom--stubborn and capped with a solid slab but ugly if they fail. There were ferocious northwest winds over the weekend. Windspeeds eased a bit on Monday as they swung to the north, back to the speeds perfect for drifting snow into avalanche starting zones. So, snow was stripped off slopes above treeline and deposited low into tracks or below treeline. Then what little snow was left was drifted higher into the paths. Observers near Telluride found new drifts more than 6 feet deep, next to areas scoured back to tundra and dirt. Remember that wind not only redistributes large amounts of snow, it also breaks down snow grains and packs them together tightly, forming cohesive windslabs that have the potential to fracture above the point of initiation and propagate over long distances. The snowpack faceted away under the cold temperatures last week, causing layers of snow grains to become angular and cohesionless. These weak layers, however thin, will not bond well with the windslabs above them. On northerly terrain, deep slab instabilities are a concern as weak snow at the base of the snowpack persists. On the sunnier aspects, the upper windslabs formed on top of various layers of crusts sandwiched around faceted snow. The snowpack is returning to the familiar San Juan stack of windslabs on facets. Scale back your expectations from earlier this season accordingly. Wednesday will be the first warm, sunny day in a long time. Expect some loose activity on steep slopes as the snow surface heats up. Avalanche Danger The avalanche danger for the Northern San Juan zone is CONSIDERABLE on all aspects near and above treeline. Below treeline the danger is MODERATE on all aspects. Be particularly careful on steep, convex, wind-loaded slopes near and above treeline. As the snow warms up, San Juan South ============== Current Keywords: MODERATE, avalanche danger, drifted, drifts, high pressure, slabs, trough, wind transport, windloaded, windslab, windslabs, Mountain Weather and Avalanche Forecast for the Southern San Juan Mountain Zone Forecast Issued on 1/1/2008 4:20:34 PM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Night Wednesday Wednesday Night Temperature(°F) 3-8 25-30 10-15 Wind Speed(mph) 0-10 5-15 5-15 Wind Direction NW SW SW Sky Cover Partly Cloudy Partly Cloudy Mostly Cloudy Snow(in) 0 0 0 Snowpack Discussion Observers in the Southern San Juan have been quiet. I'll run with the no-news-is-good-news, and assume everyone is out enjoying the snow. The last storm did not add a significant amount of snow, but strong and sustained westerly winds accompanied the snowfall. There was lots of wind transport. Expect to find drifted and windslabbed snow near and above treeline on north through east to southeast aspects. Human triggered slides remain possible near and above treeline on steep slopes with fresh slabs or drifts. Use caution on and near steep slopes with fat wind pillows, soft drifts, and the classic hard windslabs with a hollow sound. Avalanche Danger The avalanche danger is MODERATE on all aspects and elevations. Unstable slabs are possible on steep, windloaded terrain. Sangre de Christo ================= Current Keywords: avalanche danger, crossloaded, drifted, high pressure, lee , slabs, trough, whumpfing, windward, Mountain Weather and Avalanche Forecast for the Sangre De Cristo Zone Forecast Issued on 1/1/2008 4:20:15 PM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Night Wednesday Wednesday Night Temperature(°F) 10-15 27-32 10-15 Wind Speed(mph) 5-15 10-20 10-20 Wind Direction SSW SSW SSW Sky Cover Mostly Clear Partly Cloudy Partly Cloudy Snow(in) 0 0 0 Snowpack Discussion We have received no observations from the Sangre zone. The Sangres got lots of winds and missed out on the snow that fell elsewhere. Strong and persistent westerly winds scoured high elevation windward slopes and deposited the snow onto the lee aspects. Winds drifted snow low onto northeast, east, and southeast slopes. Gullies and other terrain features on a variety of aspects will be crossloaded as well. Beware of fresh wind pillows and slabs on steep slopes. Evaluate the snowpack frequently and look for obvious signs of instabilty including whumpfing, cracking, and recent avalanching. 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, MODERATE, avalanche danger, collapsing , drifted, drifting, faceted, faceting, high pressure, human triggered avalanches, sastrugi, slab, slabs, sublimating, sugary, trough, windslabs, windward, Mountain Weather and Avalanche Forecast for the Sawatch Range Zone Forecast Issued on 1/1/2008 4:22:40 PM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Night Wednesday Wednesday Night Temperature(°F) 8-13 22-27 8-13 Wind Speed(mph) 15-25 5-15 10-20 Wind Direction NW WSW W Sky Cover Mostly Clear Partly Cloudy Partly Cloudy Snow(in) 0 0 0 Snowpack Discussion The southern Sawatch picked up as much as 17 inches of snow out of the last storm. Not bad, but the real story was the winds. Strong and sustained westerly winds blasted the peaks. Near and above treeline, most of the storm snow, and most of the old snow, was scoured off windward faces. The snow went somewhere--some sublimating off to Kansas--but most of the snow was drifted and loaded. You will encounter widespread hard slabs, cross drifting, and plenty of "wind jacked" sastrugi near and above treeline. Westerly aspects and wind exposed spots will be scoured to the ground. The new slabs are sitting on older snow that faceted during last year's cold spell. The cold temperatures drove the faceting process, resulting in lots of weak, sugary snow. Not the best foundation to put big, ugly slabs on top of. You will find some wind effected snow below treeline on north, northeast, east, and southeast aspects. It is the same problem of windslabs on top of weak faceted snow, but the slabs may be softer and offer better riding conditions. Out of the wind, the storm snow can still form a slab, if the old snow underneath is especially faceted. The softer slabs can be sneaky, because they do not feel like slabs or much of an avalanche problem. Carefully evaluate the snowpack well before you get onto or underneath steep slopes. Watch for obvious signs of instability including recent avalanching, cracking, collapsing and stronger over weaker layering. Wednesday will be the first warm, sunny day in a while. Expect some wet loose activity from steep, sunny slopes below treeline. Avalanche Danger The avalanche danger is CONSIDERABLE on all slopes near and above treeline, and on north, northeast, east, and southeast aspects below treeline. Human triggered avalanches are probable on steep slopes with fresh windslabs. On other aspects below treeline the danger is MODERATE. Steamboat ========= Current Keywords: CONSIDERABLE, avalanche danger, cross loaded, crust, high pressure, human triggered avalanches, natural, powder , slab, slabs, stress, trough, weak layers, Mountain Weather and Avalanche Forecast for the Steamboat and Parks Range Zone Forecast Issued on 1/1/2008 6:58:21 AM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Tuesday Night Wednesday Temperature(°F) 13-18 -3-2 20-25 Wind Speed(mph) 15-25 10-20 10-20 Wind Direction W WSW WSW Sky Cover Mostly Clear Clear Partly Cloudy Snow(in) 0 0 0 Snowpack Discussion Up to 2.5 inches of water (25 to 35 inches of snow) fell since Saturday in favored locations in the Steamboat Zone. Strong, 30 to 40 mph with gusts to 60 , westerly winds accompanied the snow, rapidly loading easterly slopes. Observers noted several fresh natural slides in the Oak Creek Canyon Group. Fractures ranged from 2 to 4 feet deep and ran up to 500 feet. Poor visibility kept observations in the Flat Tops, Elkheads and Park Range to a minimum. Prior to the storm, the snow surface consisted of weak grains that will not readily bond with new snow. There are some other weak layers, too. Observers near the ski area found easy to moderate stability test results on a thin crust that is now buried about 3 feet below the surface. This is a perfect depth to be triggered by backcountry riders--close enough to the surface to be impacted by the additional stress of a rider, but deep enough to stay in place by itself, and deep enough to cause an unpleasant-sized avalanche. Human triggered slides are probable, particularly on north to east aspects today. You can expect to find the most reactive slabs on exposed northeast through southeast aspects, although winds blew so hard that pockets of slab formed even in thick trees. Look for wind pillows and cross loaded terrain features. While slides will not likely step down into the weak layers at the base to the snowpack, it remains a possibility. Don't let powder fever get the best of you! Use conservative decision making if traveling in the backcountry today. Have a safe and happy new year! Avalanche Danger The avalanche danger in the Steamboat Zone is CONSIDERABLE on all aspects and elevations. Unstable slabs are probable on steep slopes. Human triggered avalanches are probable in steep terrain. 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, collapsing , creep, crossloaded, drifting, facet, faceted, faceting, facets, high pressure, human triggered, natural avalanches, paths, sastrugi, slab, slabs, sugary, trough, wind slabs, windloading, windward, Mountain Weather and Avalanche Forecast for the Vail and Summit County Zone Forecast Issued on 1/1/2008 4:23:47 PM Forecaster: Spencer Logan Weather Synopsis High pressure is building, bringing relief / from Boreas's fury, temper, and strength. / He sent two thousand seven out in style, / Backing up traffic many hours and miles. / One final, parting kiss to say good bye, / As around midnight the jet stream dipped down / to blast the peaks, gusts to sixty four / on Monarch, but down from the day before. / By dawn the jet has moved off to the east. / Zephyrus comes, airmass stable and dry, / West and northwest winds, at moderate speeds. / The temperatures will rise, slowly at first, / Warming on Wednesday and into the week. / Some clouds to the south slide under the ridge, / Which breaks down Friday as a trough plows east. Two thousand eight arrives sunny and mild, / With precarious snow on a holiday, / A combo that should give everyone pause, / Poetry, jokes, celebration aside. / Make yourself a New Year's resolution: / Know obvious clues to unstable snow, / Select terrain condition appropriate, / Travel smart once you're in the dragon's den / From island to island one at a time, / Carry the right gear and know how it works. / Combine these with some healthy common sense, / You can have a great backcountry New Year. Weather Tuesday Night Wednesday Wednesday Night Temperature(°F) -5 to 0 20-25 0-5 Wind Speed(mph) 15-25 10-20 10-20 Wind Direction WSW WSW SW Sky Cover Mostly Clear Mostly Clear Partly Cloudy Snow(in) 0 0 0 Snowpack Discussion With the clearing weather, observers have been taking stock of the avalanche activity during and after the storm. There were two close calls in the Front Range Zone. There were natural avalanches on most aspects above treeline, with southerly and crossloaded paths particularly active. Control work triggered avalanches on north, east, southeast, and west aspects, some breaking 6 feet deep. Snow accumulations from the last storm were 7-15 inches. Not bad, but the real story was the winds. Strong and sustained westerly winds blasted the peaks and reshaped the snowscape. Most slopes, regardless of aspects or elevation have some kind of wind effected snow on them. Near and above treeline, most of the storm snow, and most of the old snow, was scoured off windward faces. The snow went somewhere, and you will encounter widespread hard slabs, cross drifting, and plenty of "wind jacked" sastrugi near and above treeline. Westerly aspects and wind exposed spots will be scoured to the ground. The new slabs are sitting on older snow that faceted during the last cold spell. The cold temperatures drove the faceting process, resulting in lots of weak, sugary snow. Not the best foundation to put big, ugly slabs on top of. There will be two instability issues to look out for. First is the continued facet growth near the ground. Full depth avalanches have crept back into the picture as the facets get bigger and weaker. The second issue is the newly formed wind slabs on the surface. Hard slabs act like sleeping tigers. It is easy to creep closer to them while they are sleeping, but you do not want to wake them up. Be very mindful of where you get cracking. Hard slabs tend to not crack too much until you are near the edges of the slab, then they zipper open with lightning speed. Watch for obvious signs of instability including recent avalanching, cracking, collapsing and stronger over weaker layering. Avoid traveling on or below steep exposed slopes above treeline. Human triggered slides are probable above treeline on north through east to south aspects with recent windloading. Avalanche Danger The avalanche danger in the Vail Summit Zone is CONSIDERABLE above treeline on north, northeast, east, southeast, and south aspects. The danger is MODERATE on other aspects above treeline. Near treeline the danger is MODERATE on all aspects. Below treeline the danger is MODERATE on north, northeast, east, southeast, and south aspects, and LOW on other aspects.