The threat of overnight snow and frost forced Catterick officials to call an inspection at 8am ahead of the meeting on Friday.
Ten millimetres of rainfall within the last 24 hours has been compounded by a light covering of snow and sub-zero temperatures.
Further wintry showers have again been forecast, with overnight temperatures set to drop to minus 1C.
The going is currently soft.
Clerk of the course Fiona Needham said: "We have a light covering of snow this morning but no frost.
"There is further snow forecast, but mostly to the west of us, but a slight freeze overnight is also forecast.
"We couldn't race at the moment but it wouldn't take much to shift it and it is supposed to be a bit warmer tomorrow."