The meetings at Kempton and Lingfield on Saturday face inspections early on race-day morning.
Kempton officials have called a 7.30am inspection, with the all-weather circuit at the Sunbury venue covered in snow.
Clerk of the course Barney Clifford, who is currently in France, said: "They've had three inches of snow, it's still snowing and there is more snow forecast. The course is not raceable now and we'll just have to see what they can achieve."
He added: "It is not just about the track, there is the infrastructure and everything else to consider. They will inspect at 7.30am and they'll know what can be achieved by then."
Lingfield will inspect at 7am after losing Friday's card due to snow, clerk of the course Neil Mackenzie Ross finally admitting defeat after staging inspections at 8am, 10am and 11am. He called off the meeting before a planned noon check.
He said: "We are just struggling with the machinery on the track. We can't get it round quickly enough to keep the track fit for racing. While it is not particularly heavy snow, it is coming down continuously, which means we aren't able to keep the track safe and fit.
"We need to go and take stock of the situation, keep working the track for the rest of the day and overnight if needs be."
Friday's meetings at Wolverhampton and Chepstow were also abandoned on raceday due to snow, along with Saturday's at Haydock and Taunton.
Clerk of the course Kirkland Tellwright was due to inspect the Haydock track at 8.30am on Friday, but with an inch of snow already on the ground and more forecast, he made an early call.
Taunton clerk of course Michael Trickey said: "We have had about three inches of snow and it is still snowing. I couldn't actually get to the track as I live 40 miles away, but we've had to abandon."
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