NORTHERN CAIRNGORMS AVALANCHE HAZARD 1500 HRS MON 27-12-99 The significant snow transport of the past few days has eased considerably. There is extensive evidence of cross loading on the gullies of Coire an Sneachda but the slab has tightened in and numerous slope tests showed no clean or easy shears. Temperatures have been reasonably steady in the -3 to -5 degree range at 1000 metres. The avalanche hazard is Category 3 (Considerable) AVALANCHE HAZARD OUTLOOK TUE 28-12-99 The slab may still be triggered in isolated locations, mainly on North to East above 850 metres. In some locations this stiff surface layer is sitting on a low density layer. It will need attention over the next few days. Avalanche hazard will be Category 3 (Considerable). CLIMBING CONDITIONS SNOW DISTRIBUTION: Cornice build up is light to moderate, some erosion noted on north aspect. ICING: Still extensive rime and glazed surface on wind exposed aspects. In the lee, foot penetration is up to 20 centimetres. COMMENT: Snow depth over 4 metres in collection and deposition zones above 1000 metres. LOCHABER AVALANCHE HAZARD 1500 HRS MON 27/12/99 Large areas of soft unconsolidated snow exist in corries and gullies with an aspect from N through E to SE. On scarp slopes and at the tops of gullies of these aspects, soft unstable slab is present. The avalanche hazard is Considerable (Category 3). Soft unstable cornices are also present above these aspects. AVALANCHE HAZARD OUTLOOK TUE 28/12/99 The cold showery WNW airflow is expected to continue overnight and during Tuesday. Areas of unstable snow will continue to form, greatest accumulations being at the tops of gullies and on scarp slopes with a N through E to SE aspect. Avalanches are likely in these locations. Large areas of soft unconsolidated snow will remain in many corries and gullies. The avalanche hazard will be Considerable (Category 3). Cornices will continue to form and be prone to collapse. CLIMBING CONDITIONS SNOW DISTRIBUTION: Good general cover above 300m. ICING: Remaining cold at all levels overnight and during Tuesday. COMMENT: Deep soft snow in corrie floors making walking challenging. GLENCOE AVALANCHE HAZARD 1500 HRS MON 27/12/99 New snow above 300m has drifted into all sheltered areas.The snowpack is generally soft at all levels with the greatest accumulations being in N to SE facing corries and in sheltered gullies above 800m. Deep unstable windslab has formed on steep slopes with a N through to SE aspect and in all sheltered gullies. In these areas the avalanche hazard is Considerable (Category 3). AVALANCHE HAZARD OUTLOOK TUE 28/12/99 Cold conditions with snow showers at all levels and fresh Westerly winds can be expected overnight and during Tuesday. Unstable windslab will continue to form above 600m on N through to SE slopes and in all sheltered gullies. Avalanches are likely where deep accumulations of windslab form on steeper slopes and in these areas the avalanche hazard will be Considerable (Category 3). Cornices will be prone to collapse. CLIMBING CONDITIONS SNOW DISTRIBUTION: New snow above 300m. ICING: Ice re-forming above 500m. COMMENT: Areas of deep unconsolidated snow require great caution and careful route planning. SOUTHERN CAIRNGORMS AVALANCHE HAZARD 1500 HRS MON 27/12/99 Localised areas of soft slab and unconsolidated snow exist on all aspects down to valley level. Above 850m on steeper slopes in sheltered locations, shear tests revealed poor stability in surface layers. The avalanche hazard is Considerable (Category 3). Exposed areas remain scoured and cornices although firming up remain suspect. AVALANCHE HAZARD OUTLOOK TUE 28/12/99 Snow showers overnight and during the day will leave new accumulations on all aspects. Where there is any depth to the snow colder temperatures will continue to weaken surface layers and where new deposits overlie these localised areas the snowpack will be moderately to weakly bonded. The avalanche hazard will remain Considerable (Category 3). CLIMBING CONDITIONS SNOW DISTRIBUTION: A mix of everything on all aspects but generally good cover. ICING: Showing some improvement but needs some work on the climbs. COMMENT: Ski touring is good at the moment. CREAG MEAGAIDH AVALANCHE HAZARD 1500 HRS MON 27/12/99 Over the last few days, deep accumulations of very unstable windslab have formed in any sheltered gully or hollow on N through E to SE aspects over 750m. Spontaneous avalanches were observed in Coire a' Chriochairein. At lower levels deep soft snow abounds. Large cornices are also present over N through E to SE aspects. Considerable (Category 3) avalanche hazard. AVALANCHE HAZARD OUTLOOK TUE 28/12/99 Continuing snow showers on a moderate WNW/W wind will continue to load existing unstable windslab deposits found on N through E to SE aspects above 750m. . Sheltered gullies and hollows will be most affected. In addition very cold temperatures will mean that there will be little consolidation of the existing snowpack. The avalanche hazard will remain Considerable (Category 3) with avalanches likely in the above mentioned areas. CLIMBING CONDITIONS SNOW DISTRIBUTION: Snow at all levels. No one has reached Coire Ardair yet, without being on ski. ICING: There appears to be plenty on the cliffs, but you've got to get there! COMMENT: Excellent ski touring conditions. -------------------------------------------------------------------------------