The Department of Infrastructure says routes over Snaefell will remain shut for at least another day.
It had hoped to reopen the Mountain Road, Beinn Y Phott Road and Tholt Y Will Road today.
However, it says gritting teams have been needed elsewhere and so all three routes will stay shut until midday on Thursday.
The DOI says it will grit arterial routes around the Island to prepare for more snow expected tonight.
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