Officials at Kelso and Fakenham will hold precautionary inspections for their respective meetings tomorrow.
The going at Kelso, which will inspect at 8am on raceday, is described as heavy but there is a concern over the forecast of frost overnight.
Clerk of the course Hazel Peplinski said: “We’ve had a mild spell and we’re perfectly raceable today and didn’t freeze last night, but tomorrow is due to be the coldest day for a long time.
“It’s due to freeze from dark, hitting minus 3C at its lowest, and the biggest concern is that we’re due a high of only 1C tomorrow.
“The ground temperature is OK at the moment and the hope would be that it is only one night of frost, not an accumulation, and that it doesn’t penetrate too deep, but we are concerned.”
Fakenham will stage an inspection at 3pm this afternoon to assess prospects for their meeting tomorrow.
The track was described as frozen in places and unraceable at 8.30am this morning and frost is the prevailing concern for officials.