Friday's meeting at Sandown is subject to an inspection at 8am.
Temperatures of zero degrees were reported overnight but that is forecast to drop with an increased wind chill and the possibility of snow flurries early on raceday morning.
Clerk of the course Andrew Cooper said: "We covered the entire course on Wednesday and we're OK at the moment, but it's hard to predict with any great degree of certainty what will happen.
"It wasn't as low as it might have been last night but this weather, with wind chill and winds, is set in now for the next few days.
"It could be colder tonight with suggestions of minus 2C and the possibility of snow flurries on Friday itself.
"Under the covers we should be fine but when you add in a minus 3C or 4C wind chill that does have an impact on the ground, there's no doubt about it, and that's the added complication.
"We're left with no choice but to inspect and see what the weather does."