The winter of 1836-1837 was exceptionally severe across the whole of Great Britain, with heavy snow, gale-force winds and freezing temperatures being recorded in locations all around the country from the end of October 1836 through to April 1837. Very heavy snowfall began across South East England, and in particular over the South Downs, on 24 December 1836, and continued unabated over the Christmas period. Strong winds at the same time created blizzard conditions, with reports of snowdrifts over ten feet high in some areas of Lewes. Unknown to the inhabitants of the town, the accumulation of snow at the top of Cliffe Hill, driven by a particularly severe gale on Christmas night, had been forming into a large cornice overhanging its almost sheer western edge. On the evening preceding the disaster, a significant build-up of snow was observed falling from the top of the hill into a timber yard close to Boulder Row. The inhabitants were warned that they could be at risk and were advised to leave their homes until the danger had passed, but for their own reasons they chose to ignore the warning.