Friday's cards at Doncaster and Huntingdon are under threat from the cold snap.
Officials at Doncaster have called a 10am inspection on Wednesday and report five inches of snow on the track ahead of their two-day fixture, which features the Sky Bet Chase on Saturday.
Clerk of the course Roderick Duncan told At The Races on Monday: "The forecast I looked at this morning for Saturday gave us a little bit of hope. It depends which forecast you look at but there are glimmers of hope.
"The forecast for Thursday night into Friday is a little bit difficult.
"We haven't got covers on. We've got a natural cover on it of snow and we'll see where that goes."
Huntingdon's meeting must pass a 9.30am inspection on Wednesday.
The track is currently covered by four inches of snow with more forecast. To compound matters, freezing temperatures are expected overnight.
Clerk of the course Sulekha Varma said: "We are holding a watching brief there and hope things improve in time with the meeting being on Friday. There is at least two to three inches of snow across the site which is enough to cause a problem."
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