Officials at Wetherby have called a precautionary inspection for 8am ahead of their fixture on Boxing Day.
Thirteen millimetres of rain was recorded at 4.30pm on Christmas Day, with the going reported as soft for the two-day 188Bet Yorkshire Christmas meeting.
The forecast is for further rain, heavy at times, over the next 12 hours or so.
Speaking earlier in the day, clerk of the course Jonjo Sanderson said: "I've got one (forecast) telling me we're going to get heavy showers and six millimetres and then dry all day tomorrow and warm.
"I've got another saying it's going to start raining from lunchtime and not stop until about six o'clock tomorrow night.
"If that comes, you'd assume it would be a significant amount and would put us in a totally different position altogether. "
Sedgefield will also hold a precautionary at 8am due to an adverse weather forecast.
The course is currently raceable with the going described as soft, good to soft in places.
However, rain was expected to move in on Christmas afternoon and continue through to Saturday's meeting. As much as 13 millimetres was expected on Friday.
Should the programme go ahead, the last fence will be omitted due to false ground on the take-off side.
Clerk of the course Sophie Barton felt it prudent to call an inspection for Saturday morning due to the latest weather prediction.
"The forecast has changed from Thursday and we are now due rain all of Saturday which is why I've called a precautionary inspection," she said.
"We're forecast up to an inch and a half with one forecaster but when I speak to that particular one we usually get half of what they say.
"I think we might be on the 15 to 20 millimetre mark, which it can take.
"It's going to be heavy ground."
In Ireland, Limerick must stage a precautionary check at 8am due to the forecast of overnight rain.
The track has endured 22 millimetres of rain since declaration time but is currently raceable, with the ground heavy.
No problems are reported at Leopardstown or Down Royal.