OCR Text |
Show No. 59- 1 ALTA, UTAH 24- 25 January 1959 WEATHER FACTORS A severe storm began the nightof 24 January and continued into the morning of 25 January. Precipitation intensity was average with wind velocity at 5- 10 m. p. h. Temperature remained around 26- 28 degrees. Six inches of new snow fell during the course of the storm. This was the beginning of a storm cycle that lasted until the beginning of February. ACCIDENT SUMMARY On 25 January artillery fire and test skiing in the ski area failed to reveal any siide danger. Most of the area was consequently opened for use. Late in the afternoon two skiers traversed the steep slopes above Wildcat Bowl and climbed high under the cornices above Westward Ho. Their path took them about 50 feet higher up the slope than the usual traverse, and above the area which had been test skied earlier in the day. At the steepest part of the slope, just under the cornice, they dislodged a deep climax slab which carried them both a short distance down the hill. They suffered minor bruises and equipment damage. Both were experienced skiers, and one was a trainee in the avalanche school. Shortly afterwards an Alta Lodge employee and a guest skied through the Eagle's Nest in the area known as High Nowhere. As they did so, they dislodged a climax slab under the steep cliffs of North Rustler. The employee was carried clear to the bottom of the slope, but escaped without injury. AVALANCHE DATA The storm occurring on 24- 25 January was of little consequence in itself, but provided sufficient load to trigger climax slide conditions, and provided clear warning of impending slide activity as more snow was added by storms on the following days. The highly unstable nature of the base, with at least two good falls of powder resting on a smooth rain crust, had indicated that extensive avalanching was to be expected. Early on the morning of the 25th a climax slide occurred on Superior, blocking the road. The slides later in the day on Westward Ho and North Rustler indicated that avalanche hazard was high and that danger would increase as storm conditions persisted. 47 |