Aspen ===== Current Keywords: CONSIDERABLE, MODERATE, avalanche danger, collapsing,, denser, faceted, facets, human triggered, human triggered avalanches, inversions, powder , shovel, whumpfing, windslabs, Mountain Weather and Avalanche Forecast for the Aspen Zone Forecast Issued on 12/3/2007 7:09:24 AM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Monday Night Tuesday Temperature(°F) 30-35 20-25 30-35 Wind Speed(mph) 10-20 15-25 10-20 Wind Direction WNW WNW NW Sky Cover Clear Mostly Clear Mostly Cloudy Snow(in) 0 0 1-3 Snowpack Discussion Storm totals across the Aspen Zone ranged from 26-40 inches. Strong southwest winds transported new snow onto northeasterly aspects during the storm. Winds veered to the west as the storm cleared, loading east and southeasterly slopes. Near and above treeline the winds built fresh windslabs on weak, faceted snow from earlier in the season. You will find the combination of weak facets and new windslabs on slopes facing northwest, through northeast, through east. Look for cross loading of ridges gullies and other terrain features as well. Observers confirmed how tender the newly loaded layers are, reporting cracking, collapsing, whumpfing and easily triggered small slides on north through easterly aspects. Out of the wind, the storm came in "right side up," with denser at the start and getting lighter as the temperatures cooled. Human triggered avalanches are likely today, especially on steep northwest, north, northeast, east, and southeast facing slopes, near and above treeline. Given the weak nature of the old snowpack on these aspects, large avalanches are possible. Do not let the nice weather and draw of fresh powder draw you into making bad a bad decision. Be careful out there! Avalanche Danger The avalanche danger in the Aspen Zone is CONSIDERABLE on northwest, north, northeast, and east aspects at all elevations. Human triggered avalanches are probable on steep slopes today. On other aspects the danger is MODERATE. Your backcountry observations are very important to us. Observations can be submitted to [60]caic@qwest.net . Front Range =========== Current Keywords: CONSIDERABLE, MODERATE, avalanche danger, collapse,, collapsing , crossloading, facets, human triggered, inversions, natural, naturals, shovel, slabs, whumpfing, wind loaded, windslabs, Mountain Weather and Avalanche Forecast for the Front Range Zone Forecast Issued on 12/3/2007 8:14:31 AM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Monday Night Tuesday Temperature(°F) 27-32 20-25 28-33 Wind Speed(mph) 15-25 15-25 15-25 G50 Wind Direction WNW WNW WNW Sky Cover Mostly Cloudy Mostly Cloudy Mostly Cloudy Snow(in) 0 0 1-3 Snowpack Discussion The Front Range Zone received about a foot of fresh snow in the last storm. Observers noted numerous human triggered and natural slides throughout the zone this weekend. Triggered avalanches predominantly occurred on north and easterly aspects at all elevations. Most were small, but ran to the ground. Most natural activity occurred on heavily wind loaded slopes just below ridges. The largest reported naturals were in the Berthoud Pass area. Backcountry travelers also reported extensive cracking, collapsing and whumpfing as well (click on the thumbnail photo below). With snow covering all aspects, we have moved into a more wide-spread avalanche problem. Expect to find tender slabs in the backcountry today. Winds have blown consistently out of the west and southwest, loading already sensitive north and easterly aspects. The winds swirled around below ridge tops and down valleys crossloading lots of terrain, even in openings below treeline. Fresh windslabs are perched on the weak faced snow that formed early this season. The facets make a poor foundation, and even soft new snow can collapse, crack, and avalanche. ACCIDENT UPDATE The accident occurred mid-afternoon Sunday. A party of 3 went to Hot Dog Bowl, south of Zimmerman Lake and east of the Pass. The Bowl has a northerly aspect, tops out around 11,200', gets wind loaded, and had weak snow prior to the weekend storm. One person was caught and fully buried. Initial reports are of a 2 meter deep burial. The other party members found and uncovered the victim in short order, a fantastic rescue. The victim was flown out after rescue for advanced medical care. Everyone should cross their fingers or pray that he makes a fully recovery. Avalanche Danger The avalanche danger is CONSIDERABLE on northwest, north, northeast, east and southeast aspects at all elevations. Human triggered avalanches are probable today. The avalanche danger is MODERATE on other aspects. Grand Mesa ========== Current Keywords: LOW, MODERATE, avalanche danger, dense, inversions, precipitation , settle, shovel, Mountain Weather and Avalanche Forecast for the Grand Mesa Zone Forecast Issued on 12/3/2007 2:47:02 PM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Night Tuesday Tuesday Night Temperature(°F) 27-32 38-43 27-32 Wind Speed(mph) 5-15 10-20 10-20 Wind Direction NW NW W Sky Cover Mostly Clear Partly Cloudy Overcast Snow(in) 0 Tr 0-2 Snowpack Discussion Storm totals from the weekend on the Grand Mesa were in the 20-25 inch range. Below around 9500 feet much of the precipitation was rain. Above the snowline, the storm snow was probably quite dense, as it had high water content and the temperatures were quite warm. This will help new snow to settle and bond. The avalanche danger is low where new snow fell on bare ground. However, the patches of old snow were quite weak, and the new snow layers on top may be sensitive to the weight of a backcountry traveler. Watch out for loose avalanches on any slope steeper than about 35 degrees. The most likely place to trigger an avalanche is on high elevation steep north, northeast, or east aspect. The consequences of being caught in even a small slide could be quite severe if it pushes you into a pile of rocks, stand of trees, or a gully. Avalanche Danger The avalanche danger is MODERATE on steep N-NE-E slopes at the higher elevations, where there are pockets of old snow. The danger is LOW on other aspects. Watch for loose avalanches on steep, sunny slopes. San Juan North ============== Current Keywords: CONSIDERABLE, MODERATE, collapsing , facets, inversions, natural, powder , settles, settling, shovel, slab, slabs, whumphing, wind slab, Mountain Weather and Avalanche Forecast for the Northern San Juan Mountain Zone Forecast Issued on 12/3/2007 3:54:11 PM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Night Tuesday Tuesday Night Temperature(°F) 25-30 38-43 25-30 Wind Speed(mph) 10-20 15-25 10-20 Wind Direction NNW NNW WNW Sky Cover Clear Partly Cloudy Mostly Cloudy Snow(in) 0 0 0 Snowpack Discussion The weekend snow is settling quickly and becoming more cohesive. This is positive where the snow fell on bare ground. It's turning into a good base. The problem are the slopes that had old snow prior to the storm. All those old, weak facets are now topped by a strengthening slab. Natural activity has tapered off as the slab settles. Human triggered avalanches are still possible. Stronger slabs can lure you onto steeper and more exposed slopes, then fracture fairly large. The weekend storm quickly returned us to a common Colorado snowpack problem. Winds were southwesterly, then westerly, finally swinging to the northwest after the storm cleared. With plenty of snow to transport, particularly from northerly slopes, you can find wind slab on most aspects on open slopes. Wind speeds as high as we've been having can load slopes well below ridgeline elevations and affect the snow surface below treeline as well. Numerous natural and triggered avalanches were reported over the weekend. The majority of the observed activity occurred on northwest, north, and northeast aspects near and above treeline. Those same sloped had the weakest old snow layers underneath the storm snow. Observers also reported activity on east and southeast aspects, and a few slides below treeline. Most of the avalanches ran down to the old snow or the ground, three to five feet deep and up to several hundred feet wide. Backcountry observers noted all the classic signs of instability including cracking, collapsing and whumphing this weekend. Backcountry travelers will undoubtedly be eager to get out on the snow this relatively warm, bluebird day today. The temptation will be great as we haven't had many powder days yet this season. This is a time to be very cautious - do not jump into a slope just because you are powder starved! Use sound decision making when traveling in the backcountry and consider the consequences of being caught in even a small slide. Avalanche Danger On northwest, north, northeast aspects, the danger is CONSIDERABLE at all elevations. On east and southeast aspects, the danger is CONSIDERABLE near and above treeline, and MODERATE below treeline. On south, southwest and west aspects, the danger is MODERATE. The stability is improving, but unstable slabs are still probable on San Juan South ============== Current Keywords: LOW, MODERATE, avalanche danger, crusts, dense, facets, inversions, powder, , settle, shovel, slabs, surface hoar, weak layers, windloaded, Mountain Weather and Avalanche Forecast for the Southern San Juan Mountain Zone Forecast Issued on 12/3/2007 3:29:22 PM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Night Tuesday Tuesday Night Temperature(°F) 25-30 40-45 25-30 Wind Speed(mph) 15-25 10-20 10-20 Wind Direction NNW NW W Sky Cover Partly Cloudy Mostly Clear Mostly Cloudy Snow(in) 0 0 0 Snowpack Discussion The Southern San Juans received almost 4 feet of snow from the weekend storm. Conditions went from dry to wintery is two days. The inital snow cam in warm and dense. Temperatures dropped during the storm, resulting in lighter snow on top. As storm-snow instabilites settle out, the snowpack turns into a good base under powder, with little to form weak layers. You might be able to find pockets of weak, old facets with triggerable slabs on top. Do not jump blindly onto steep, north, northeast, or east facing slopes. Enjoy the good conditions while they last. Sun crusts are forming on the sunny slopes, and there is surface hoar on shady slopes. Those could turn into perfect weak layers for the next storm. Avalanche Danger The avalanche danger is LOW with pockets of MODERATE on steep north, northeast, and east aspects near and above treeline. Watch for steep pockets of windloaded snow with old facets underneath. Sangre de Christo ================= Current Keywords: avalanche danger, consolidate, crossloading, drifts, inversions, shovel, sluffs, windslabs, Mountain Weather and Avalanche Forecast for the Sangre De Cristo Zone Forecast Issued on 12/3/2007 2:41:02 PM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Night Tuesday Tuesday Night Temperature(°F) 30-35 38-43 27-33 Wind Speed(mph) 20-30 25-35 25-35 Wind Direction NW NW W Sky Cover Mostly Clear Partly Cloudy Mostly Cloudy Snow(in) 0 0 0 Snowpack Discussion The Sangre de Cristo range picked up over an inch of water during this last storm. The new snow was quite wet and came in warm temperatures. It will probably stick pretty well to the bare ground. However, areas where there was snow prior to the storm, namely high elevation north and easterly aspects, could be sensitive. There was quite a bit of wind with this event, so thick drifts and sensitive windslabs lurk in the high-elevations areas. Strong winds continued, so expect lots of crossloading. If you are traveling in the high country you will be able to move from relatively safe to quite dangerous slopes very easily. Watch for changes in slope angle and aspect as these elements greatly affect snow stability. In general, the avalanche danger will increase and you move up in elevation or onto steeper and/or shadier aspects. The most likely place to trigger an avalanche is on steep slopes that face northwest, north, northeast and east and are near and above treeline. The warm temperatures will consolidate the storm snow. Loose wet sluffs are possible on steep rocky southerly slopes. 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 [60]caic@qwest.net Sawatch ======= Current Keywords: MODERATE, cross loading, crossloaded, crusts, drifted, drifts, facets, inversions, shovel, slabs, windloaded, windslabs, Mountain Weather and Avalanche Forecast for the Sawatch Range Zone Forecast Issued on 12/3/2007 3:01:16 PM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Night Tuesday Tuesday Night Temperature(°F) 18-23 30-35 18-23 Wind Speed(mph) 20-30 15-25 20-30 Wind Direction WNW WNW W Sky Cover Partly Cloudy Mostly Cloudy Mostly Cloudy Snow(in) 0 0 0 Snowpack Discussion About a foot of snow fell during the storm. Strong southwest, west, and now northwest winds drifted and crossloaded snow into gullies and behind terrain features. Some of the drifts and new snow are sitting on older, weak snow. Coverage prior to the storm was spotty, with the old snow remaining in steep, northerly gullies and pockets. Facets and crusts make up the stratigraphy of old snow, which make for poor bonding with new snow. Expect to find sensitive slabs in the backcountry. An observer reported tender snow over the weekend. Our biggest concern remains in the southern portion of the zone, specifically the Monarch Pass area, where more snow accumulated. Moderate to strong winds out of the southwest built fresh windslabs, especially near and above treeline. Look for loading on northerly aspects and cross loading on ridges, gullies and other terrain features. The most likely place to trigger an avalanche is on a steep, windloaded north, northeast, or east aspect near and above treeline, but expect some pockets on northwest and southeast aspects. Avalanche Danger The danger in the Sawatch Zone is MODERATE with pockets of CONSDIERABLE on northwest, north, northeast, east, and southeast aspects near and above treeline. You will the pockets of unstable slabs on steep, wind-loaded slopes. Please [60]send us observations if you are getting out. Steamboat ========= Current Keywords: LOW, MODERATE, avalanche danger, drifted, drifts, facets, inversions, shovel, whumpfing, windslabs, Mountain Weather and Avalanche Forecast for the Steamboat and Parks Range Zone Forecast Issued on 12/3/2007 3:04:53 PM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Night Tuesday Tuesday Night Temperature(°F) 20-25 28-33 18-23 Wind Speed(mph) 15-25 15-25 10-20 Wind Direction WNW W WNW Sky Cover Partly Cloudy Mostly Cloudy Overcast Snow(in) 0 0-3 pm 1-3 Snowpack Discussion The Steamboat Zone picked up 10 to 20 inches of new snow from the last storm, with the Bison Lake SNOTEL topping out the numbers, and Zirkel SNOTEL two inches behind. The snow on the ground prior to this week's storms was quite weak. New snow with wind has created sensitive drifts on top of the weak basal layers. Observers noted a reactive snowpack on steep, high elevation, northerly aspects where windslabs perched atop rotten facets. The old snow was quite patchy, and the avalanche danger will follow this pattern today. Beware of drifted and loaded slopes, especially on NW-N-NE- E aspects at higher elevations. Watch for signs of instability such as cracking, whumpfing, and recent avalanche activity. Consider the consequences of a bad decision before committing to steep slopes. Avalanche Danger The avalanche danger in the Steamboat Zone is MODERATE on steep northwest, north, northeast, and east aspects at higher elevations. On other aspects the avalanche danger is LOW. Vail ==== Current Keywords: CONSIDERABLE, MODERATE, avalanche danger, collapse,, collapsing,, facets, human triggered avalanches, inversions, natural, shovel, slabs, test slopes, whumpfing, wind loaded, windslabs, Mountain Weather and Avalanche Forecast for the Vail and Summit County Zone Forecast Issued on 12/3/2007 6:43:49 AM Forecaster: Spencer Logan Weather Synopsis High clouds are moving south across Colorado this afternoon. We are on the "downhill" side of a broad, shallow ridge over the western US. Upper level flow is generally west-northwest, and will stay that way for several days. Warm air has moved into the state, though many valleys have cold air pooled in them. The inversions may not break down until Wednesday. A short wave comes through Tuesday, cooling temperatures and bringing some snow to the Aspen, Vail Summit, Steamboat, and maybe Front Range Zones late afternoon and overnight. This is the start of a stormier period, with another intense storm for the weekend. If you did something to help make it snow last week, please, please do it again. Sunday afternoon, a skier was buried about 2 meters (6.5 feet) deep in an avalanche near Cameron Pass, in the northern Front Range. Their party located and dug out the skier in short order, an impressive rescue. More details in the Front Range forecast. It might be good to review some shoveling techniques. There is a good article at [59]Backcountry Access called "Strategic Shoveling," and one in the November issue of Backcountry Magazine. Weather Monday Monday Night Tuesday Temperature(°F) 25-30 20-25 27-32 Wind Speed(mph) 10-20 15-25 15-25 Wind Direction WNW WNW WNW Sky Cover Partly Cloudy Partly Cloudy Mostly Cloudy Snow(in) 0 0 0-2 Snowpack Discussion The Vail/Summit Zone received up to 16 inches of fresh snow in the last storm. Both natural and triggered avalanches occurred on north and easterly aspects at all elevations as well. Naturals predominantly slid in heavily wind loaded areas below ridgelines. Observers found out how tender the newly loaded layers are, reporting lots of cracking, collapsing, whumpfing, and easily triggered test slopes on those north through east aspects. With snow covering all aspects, we have moved into a more wide-spread avalanche problem. Expect to find tender slabs in the backcountry today. Winds have blown consistently out of the west and southwest, loading already sensitive north and easterly aspects. Fresh windslabs are perched on the weak faced snow that formed early this season. The facets make a poor foundation, and even soft new snow can collapse, crack, and avalanche. Avalanche Danger The avalanche danger is in the Vail/Summit Zone is CONSIDERABLE on NW-N-NE-E-SE aspects at all elevations. Human triggered avalanches are probable today. The avalanche danger is MODERATE on other elevations.