NORTHERN CAIRNGORMS AVALANCHE HAZARD 1500 HRS THU 18/2/99 Mild, drizzly conditions have moistened the surface layers of recent windslab that lies on many E to SE aspects. Stability is poor on these steep scarp slopes (in excess of 40 degrees inclination) above 1100m. Tests in these locations showed up easy shears immediately beneath the moist surface layer. The avalanche hazard is localised in these places but Considerable (Category 3). The snowpack on less steep ground, at lower elevations of the same aspect, is showing some early consolidation. All NW to NE facing slopes and gullies are stable. AVALANCHE HAZARD OUTLOOK FRI 19/2/99 Some snowfall is possible overnight and during Friday with SW to W winds. In the event of moderate or sustained snow showers, new marginally-stabilised windslab may accumulate on NE to SE aspects above 1000m. Where accumulations are greatest in these locations the avalanche hazard will be Considerable (Category 3). All other areas will become crusty and/or hard and stable. CLIMBING CONDITIONS SNOW DISTRIBUTION: Wet snow at all levels on Thursday. Heavy, spring snow below 800m . ICING: Still in place and will improve with imminent re-freeze. All gullies in N.Corries complete and firm. COMMENT: Perhaps not much new snow. LOCHABER AVALANCHE HAZARD 1500 HRS THU 18/2/99 A thaw at all levels has consolidated the existing snowpack. Localised areas of unstable wet snow are present, but these are generally confined to steep slope inclinations above 1000m. In these locations the avalanche hazard is Moderate (Category 2). AVALANCHE HAZARD OUTLOOK FRI 19/2/99 A return to colder conditions is expected overnight. This will freeze and stabilise all of the existing snowpack. During Friday, moderate snow showers and strong W winds are expected. Fresh areas of windslab will form during daylight hours on Friday. Accumulations will be greatest at the tops of E facing slopes and gullies. The avalanche hazard will rise to Considerable (Category 3) as these accumulations become significant during the day. CLIMBING CONDITIONS SNOW DISTRIBUTION: Main accumulations remain above 750m. ICING: Freezing at all levels during Friday. COMMENT: Old snow becoming hard frozen at all levels. Ice- axe and crampons essential for everyone venturing onto the mountains. Strong winds expected on the summits. GLENCOE AVALANCHE HAZARD 1500 HRS THU 18/2/99 Rain at all levels has softened and moistened the snowpack.There are isolated deposits of soft moist slab mainly in sheltered gullies with a N to SE aspect above 900m. Where accumulations are significant on steep slopes the avalanche hazard is Moderate (Category 2). Elsewhere the snowpack is generally stable. AVALANCHE HAZARD OUTLOOK FRI 19/2/99 Colder conditions will refreeze the existing snow cover. New snow overnight and on Friday with strong Westerly winds will form areas of poorly bonded windslab in sheltered gullies and on slopes with a NE to SE aspect mainly above 800m.The avalanche hazard will be Considerable (Category 3). Avalanches are likely in areas where deeper accumulations of windslab form. The general snowpack where exposed to the prevailing winds will develop an icy surface crust and will be very stable CLIMBING CONDITIONS SNOW DISTRIBUTION: Wet snow above 400m. ICING: Thawing ice above 600m. COMMENT: Becoming colder overnight, windy! SOUTHERN CAIRNGORMS AVALANCHE HAZARD 1500 HRS THU 18/2/99 Thaw conditions have left snow soft and moist at all levels. An unstable period overnight led to several cornice triggered avalanches in Lochnagar before the snowpack started to consolidate. The avalanche hazard is Moderate (Category 2) with the greatest hazard from remaining cornice collapse. AVALANCHE HAZARD OUTLOOK FRI 19/2/99 A windy day with freezing levels dropping and some snow showers. The snowpack will generally firm up but where new accumulations are at their greatest on scarp and steep slopes on NE to S aspects stability will be poor. The avalanche hazard will be Considerable (Category 3) with some remaining cornices requiring care. Other aspects will remain stable. CLIMBING CONDITIONS SNOW DISTRIBUTION: Mainly on N to E aspects and plateau areas. ICING: Plenty of wet ice around in Lochnagar but buttresses are lean. COMMENT: Higher paths and tracks are likely to become very icy as freezing levels drop. CREAG MEAGAIDH AVALANCHE HAZARD 1500 HRS THU 18/2/99 With the freezing level above the summits and moderate amounts of rain the new snow from the last few days has been left saturated. This unstable wet slab can still be found in gullies and hollows of a N through E to S aspect above 750m. In these areas the avalanche hazard is Considerable (Category 3). Fresh cornices remain unstable. AVALANCHE HAZARD OUTLOOK FRI 19/2/99 A return to colder conditions tomorrow with light snow showers on storm force Westerly winds will increase the stability of the existing snowpack but also start to build deposits of fresh windslab. This slab will be found in sheltered areas on N through E to S facing slopes above 750m and where significant accumulations are found the avalanche hazard will be Considerable (Category 3). In other areas the snowpack will be well-consolidated hard snow-ice. CLIMBING CONDITIONS SNOW DISTRIBUTION: Although thawing today still deep accumulations in the gullies. ICING: Thawing slightly, but should improve with colder temperatures tomorrow. COMMENT: Temporary blip today but a return to winter tomorrow. -------------------------------------------------------------------------------