Saturday's meeting at Bangor has been abandoned due to snow.
The writing was on the wall at first light after the Welsh venue sustained three inches of snow overnight.
Clerk of the course Andrew Morris said: "It's still snowing heavily and there is more to come.
"It's a hopeless case."
Saturday's fixture at Kelso has also been abandoned, this time due to a waterlogged track.
Officials were left with no option but to draw stumps following a rough night at the Borders track.
Kelso clerk of the course Hazel Peplinski tweeted: "Racing at Kelso tomorrow is sadly abandoned due to water-logged areas with no prospects of sufficient improvement."
This afternoon's meeting at Doncaster must pass a third course inspection at 11am.
Tomorrow's meeting at Doncaster is subject to a 6am inspection on raceday morning.
Stratford's jumps meeting on Saturday must pass a second course inspection at noon today.
Course officials require another assessment as further heavy rain has been forecast.
Although the course was raceable upon inspection at 6.45am this morning, a statement issued by Stratford said the track "cannot take much more precipitation".
The going is heavy.
This afternoon's fixture at Newbury passed a precautionary inspection at 7.30am.
Although the Berkshire circuit had plenty of overnight rain, conditions were deemed suitable for the jumps card to be given the go-ahead. The going is heavy.
Clerk of the course Richard Osgood said: "We had 9.6 millimetres of rain, but we are perfectly fine - apart from the fact we've taken out the open ditch in the home straight."
Osgood said plans to inspect again ahead of Saturday's fixture had not yet been finalised.