A weather front possibly bringing snow could disrupt plans to reopen one lane of the Milford road by tomorrow, New Zealand Transport Agency Southland area manager Peter Robinson said.
A front was expected to come in last night, bringing rain and possibly snow, he said.
"We're still looking to work 24 [hours a day] as much as we can."
Workers had spent yesterday afternoon drilling holes in the boulders and blasting.
"We haven't changed that forecast [to reopen one lane tomorrow] ... we're still hopeful we'll be able to keep going, but ... we can't blast in the rain."
The road has been closed since 4pm on Friday following the landslip, estimated to weigh up to 200 tonnes, located at a point known as "Red Slip", about 2km on the Milford side of Falls Creek.
