Not untypical ….. but there’s hope!
First of all Happy New Year to you all from a wild and wintry Northern Cairngorms.
The conditions are still very up and down on the mountains and we are presently experiencing weather patterns that seem to be quite typical the early winter (Dec & Jan), which are frequent freeze thaw cycles accompanied by sometimes violent storms. We are presently experiencing the 3rd violent storm of the winter. A very active cold front past through on Friday night resulting in a dramatic 11 deg C drop in temperature with Cairngorm Summit (1245m) temperature going from +4 to -7 deg C in 9 hours. Some websites are indicating it was as much as a 17 deg change which I doubt since in Boat of Garten (230m) only experienced an 8 deg change. As you might expect with such contrasting air masses abutting against each other the precipitation was intense as the front passed through – heavy rain at low levels at least which quickly turned to snow at all levels. With this very cold air passing over a relatively warm sea on it way to us an unstable airflow is being created i.e. moist relatively warm air (0 deg C) overlaid by very cold dry air. The moist air is then plume-ing up into the cold air forming tall clouds and dropping its moisture in the form of intense snow showers with brief sunny spells (cold dry air).
Up until this point on the hill we have had a mix of wintry spells and thaws which has meant there hasn’t been any appreciable net accumulation of the snow pack except in e.g. the Snow-holing sites. Generally away from the main gulley lines climbs have been in condition but on the thin side with thaws then knocking things back to square one.
A brief thaw is forecast during the latter part of Sunday with the weather charts indicating temperatures remaining below freezing on the mountains from Monday onwards. More snowfall is indicated during this period so let’s hope it stays on the hills
Best wishes and safe climbing,
Mountain Weather Information Service – www.mwis.org.uk
Scottish Avalanche Information Service – www.sais.gov.uk
Cairngorm Mountain – www.cairngormmountain.org