Thursday's meeting at Wincanton must pass an 8am precautionary inspection on raceday morning.
Although the Somerset circuit is raceable, course officials are taking no chances.
Overnight temperatures are set to drop to minus 2C, but the inspection has been called in case the frost is sharper than has been forecast.
Clerk of the course Barry Johnson said: "I'm very confident we'll be fine - we'll be OK with -2C - but some forecasts are predicting -4C.
"There's no frost in the ground now, but the ground is quite wet.
"It's very much a precautionary inspection."