NORTHERN CAIRNGORMS AVALANCHE HAZARD 1500 HRS SUN 10/3/02 It was a mostly clear night followed by a day with heavy, near continuous, snow showers and winds from the South-West. The loading pattern has changed and now the new slab is on a North-East aspect above 900 metres. Slab instability still exists on other Easterly aspects. Observations of avalanche activity were limited by poor visibility and slow travel conditions. The avalanche hazard is High (Category 4). AVALANCHE HAZARD OUTLOOK MON 11/3/02 Temperatures at the summit will remain cold with additional snow showers, some heavy. Winds will be from the South- West. Above 900 metres mainly on North-East through to Southerly aspects avalanches will occur due to storm instability and older previously identified weaknesses in the snowpack. The shear layer reported is where a firm slab lies on a soft, dry and cold layer. The avalanche hazard will be High (Category 4). CLIMBING CONDITIONS SNOW DISTRIBUTION: Surface wet snow up to about 650 metres, dry above. ICING: Should be improving where exposed. COMMENT: Careful terrain choice required while the storm instability exists. LOCHABER AVALANCHE HAZARD 1500 HRS SUN 10/3/02 Strong SE winds with heavy amounts of snow overnight and during Sunday have formed fresh areas unstable soft slab. Under test this slab fails easily, with shears up to 50cm obtained. Greatest accumulations are on sheltered slopes and gullies with W, NW and N aspects. With winds veering to the SW later on Sunday NE and E aspects are becoming affected. The avalanche hazard is High (Category 4). Cornices forming. Windblown slopes are scoured and hard frozen. AVALANCHE HAZARD OUTLOOK MON 11/3/02 Snow showers and storm force SW winds will affect the area in the next 24hrs. Unstable windslab will form on sheltered aspects. Significant accumulations will be on steep slopes and gullies with NW to N though to E aspects above 800m, where avalanches will occur. The avalanche hazard will be High (Category 4). Fresh cornices will be prone to collapse. Windblown slopes will be hard frozen and generally stable. CLIMBING CONDITIONS SNOW DISTRIBUTION: Fresh snow at all levels today (10/3/02) ICING: Freezing level rising to around 800m on Monday. COMMENT: Storm force SW winds expected. Caution advised with regards to route choice, approaches and exits. GLENCOE AVALANCHE HAZARD 1500 HRS SUN 10/3/02 Heavy prolonged snowfall today and strong South-East to South-West winds have rapidly formed windslab. Depths of up to 0.75 metre of fresh slab were noted in many gullies sheltered from the prevailing winds and on slopes with a West through North to Easterly aspect. These deep windslab accumulations are very unstable particularly above the 850m level. The Avalanche hazard is High (Category 4). Fresh debris noted below NE slopes to day. AVALANCHE HAZARD OUTLOOK MON 11/3/02 A very strong South-Westerly airflow with frequent snow showers will add further loading to existing weakly bonded windslab in all sheltered gullies and on slopes with a North to East aspect. Wind transport will be a major feature of the period with predicted speeds of around 70 mph. Deep unstable windslab will be present in many sheltered locations. Avalanches will occur in many locations. The avalanche hazard will be High (Category 4). CLIMBING CONDITIONS SNOW DISTRIBUTION: New snow above 300m ICING: Mostly buried under fresh snow COMMENT: Stormy conditions expected for period Windslab accumulations will be very weakly bonded. Fresh cornices will be weak and prone to collapse SOUTHERN CAIRNGORMS AVALANCHE HAZARD 1500 HRS SUN 10/3/02 Heavy snow and subsequent drifting have formed unstable windslab in very sheltered locations on N to E aspects. Above 850 metres these rapidly forming deposits are highly layered and are weakly bonded within themselves and to the snow-ice layer beneath. The avalanche hazard is High (Category 4). Exposed areas are scoured and icy. AVALANCHE HAZARD OUTLOOK MON 11/3/02 Further snow showers on storm force winds will continue to build weakly bonded deposits in very sheltered locations on N to E aspects above 850 metres. Drifting of deposits will continue between the showers and new accumulations will form rapidly and demonstrate very poor stability. The avalanche hazard will be High (Category 4) and avalanches will occur. Stability of newly formed cornices will be suspect. CLIMBING CONDITIONS SNOW DISTRIBUTION: New snow from valley level. Drifts on lee slopes from 500 metres. ICING: Poor observation conditions today. COMMENT: New cornices will be fragile. CREAG MEAGAIDH AVALANCHE HAZARD 1500 HRS SUN 10/3/02 Heavy snowfall has taken place on variable moderate to strong winds throughout the period. Weakly bonded windslab exists on most aspects. North-West through East to South aspects above 800 metres are particularly affected. Field tests produced easy shearing of deep slab and several weak sub-surface layers exist. The avalanche hazard is High (Category 4); avalanche activity was observed on North to East aspects. AVALANCHE HAZARD OUTLOOK MON 11/3/02 Snow is to continue throughout the period on severe storm force South-West winds. Snow transport will be significant due to wind strength and very weak windslab will be present as temperatures remain below freezing. Triggering is probable with low additional loads. Avalanches will occur mainly on North-West through East to South aspects above 800 metres. The avalanche hazard will be High (Category 4). Debris run outs will be long. Large unstable cornices will continue to build on North to East aspects. CLIMBING CONDITIONS SNOW DISTRIBUTION: Heavy snowfall at all levels. ICING: Mostly buried. COMMENT: Winds of 80 mph forecast!! -------------------------------------------------------------------------------