Western Wyoming Avalanche Advisory Jackson Ranger District, POB 1689, Jackson WY 83001 Issued: Sat December 31, 2005 4:33 PM SITUATION: Intense snowfall, strong winds and warm temperatures have created DANGEROUS unstable conditions on a variety of aspects and slope angles. Up to 5 inches of new snow fell today at the upper elevation, resulting in storm totals since Monday of 53 inches of new snow containing 5.5 inches of moisture. Natural and artificially triggered slab avalanches up to 4 feet in depth have been observed. Today, temperatures remained below freezing at the upper elevations, rising into the upper 20s with the valley hovering just above freezing. FORECAST FOR Sunday January 01, 2006 : The second half of a potent storm system is fast approach the area and conditions should deteriorate the remainder of the day and into the evening. Snowfall should be heavy at times by this evening, and continuing overnight and into Sunday morning. Winds should also be on the increase out of the Southwest ahead of the system, veering to the West or Northwest on Sunday. Colder air will also filter into the area later this evening. Additional snowfall amounts should range from 8 to 12 inches in many mountain locations by Sunday morning. Scattered snow showers will continue Sunday afternoon before a brief break occurs. AVALANCHE HAZARD FOR THE TETON, TOGWOTEE PASS/CONTINENTAL DIVIDE AND GREYS RIVER/SOUTHWEST TRAILS AREAS The general avalanche hazard will remain HIGH on New Year’s Day as new unstable surface slabs continue to build and add additional loads to existing slabs. Deep dangerous slab avalanches up to 6 feet in depth could be skier or snowmachine triggered or release spontaneously on steep wind loaded aspects. TRAVEL IN AVALANCHE TERRAIN IS NOT RECOMMENDED. Backcountry users are advised to consult area specific forecasts issued every morning as new information may become available and unexpected weather can change conditions. TREND FOR MONDAY AND TUESDAY : The next moist storm system will move quickly in Monday afternoon into Monday night with potential for heavy snow Monday night and into Tuesday morning. The avalanche hazard should remain HIGH as slabs continue to build.