A weather front is expected to bring heavy rain to the Homer Tunnel area from dawn and snow down to 600m, which could change the avalanche hazard rating from low to moderate.
Kevin Thompson, Milford Road Alliance manager, said controlled detonations are a possibility tomorrow.
"We'll consider control work in the afternoon, but we won't know until we see what comes."
The road will be closed from the East Gate (Hollyford) to West Gate (Chasm) at 7.30am. It is likely to remain closed until at least late afternoon.
Mr Thompson said such a closure is fairly unusual this winter: "But we've done it in the past. We try to disrupt Milford the least we can do."
Weather is forecast will continue to be unsettled through to Saturday.