Cheltenham's big Festival Trials Day on Saturday could be run 24 hours later if the meeting is abandoned.
Ground staff have been working overtime to shift the snow which fell on top of the frost sheets, which has given course officials renewed hope of the fixture going ahead.
However, more snow is forecast which would once again put the meeting in doubt.
"... in the event that the course is unraceable, Cheltenham has reached agreement with the British Horseracing Authority that, weather permitting, Festival Trials Day could instead be staged 24 hours later on Sunday, January 27," a statement from Cheltenham said.
The Trials are vital lead-up races to Britain's prestigious Cheltenham festival in March.
While the winter has released its grip ever so slightly to allow Flat racing on an artificial surface to get the show back on the road at Lingfield and Wolverhampton, the turf is still having a tough time with many meetings called off.
Prospects for Doncaster's feature meeting of the season taking place on Saturday have taken a turn for the worse.
Officials at the track sounded upbeat on Monday about the chances of an improvement in the weather coming in time to save Saturday's card, although Friday's meeting is subject to a 10am inspection on Wednesday.
However, the forecast has now changed and confidence has dipped.
The BHA has already taken measures in case there is another weekend wipeout.
A "jumpers' bumpers" card has been scheduled at Kempton on Friday, while Wolverhampton will stage an additional all-weather Flat fixture on Saturday.