Scheduled National Hunt meetings at Doncaster and Huntingdon on Friday have been abandoned because of snow on the tracks.
Doncaster's big meeting on Saturday is also under threat. Officials on Town Moor made an early call to cancel the Friday fixture due to the diminishing prospects of a thaw.
Clerk of the course Roderick Duncan said on Wednesday: "There is still snow on the track. We had a little bit of a thaw yesterday but there is still more than a covering in most places. The forecast for Thursday was 2C at best and -4C at worst, with the best forecast overnight being zero. Further snow and sleet is also in some forecasts."
The Sky Bet Chase and the rearranged StanJames.com Champion Hurdle Trial feature on Saturday's card and officials will inspect the track again at 2pm on Thursday to assess prospects.
Duncan added: "We are going to have a look for Saturday just to see if there is any improvement. Saturday daytime temperatures are a little bit better but we need an improvement in overnight temperatures for Friday. There needs to be a significant improvement in the forecast for Saturday to have a chance. We will need a real positive overnight temperature on Friday to give us an opportunity."
Huntingdon's meeting on Friday was also abandoned on Wednesday morning. With the track still covered in snow, the decision to call off the fixture following a 9.30am course inspection was a straightforward one.
Clerk of the course Sulekha Varma tweeted: "Three inches of snow still on track and no prospect of sufficient thaw."
Officials at Sedgefield are pessimistic about their chances of racing on Sunday after calling an inspection for 2pm on Thursday. Clerk of the course Phil Tuck admits the meeting is likely to be called off as the track is covered by snow, with little chance of an immediate improvement.
He said: "I think it will be a formality really as it's not looking good here. We have got quite a lot of snow on the track, maybe five inches or so, and more in other areas where the snow has drifted.
"The temperature is forecast to drop to -4C tonight which does not give us much hope, so we will have a look tomorrow."
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