Lewis Pass the Desert Rd can now expect a few snow flurries with little accumulating.
Waka Kotahi Journeys manager Tresca Forrester says the main concern is ice, as cold conditions continue over the next 24 hours.
Gale southerlies are expected to develop in eastern areas including Canterbury, with the strongest winds expected on the Kaikōura Coast and Wellington.
Efforts to free a person trapped in a vehicle after a crash were being impeded by fallen power lines.
FENZ said a car crashed into a power pole on State Highway 7 near Reefton at about 8.30am.
A spokesman said a person was trapped but firefighters were unable to initially free them. They had to wait for the power authority to arrive to "make the situation safe."
A St John spokesman said one person with serious injuries has been transported to Nelson Hospital by helicopter.
Meanwhile, a tree has crashed through a kitchen in the Christchurch suburb of Cashmere.
Fire and Emergency say one crew was called out just after 5.30am to the property on Valley Rd.
Officers used spades to redirect water away from the house after a small wall collapsed.
The crew was on site for 15 minutes and no one was injured in the incident.
And a crash on Brougham St at the intersection of Strickland and Antigua Sts blocked the westbound lane for about an hour but it has since reopened.
Snow is falling heavily on Porter Heights with avalanche patrols testing ski runs this afternoon. Mount Hutt's also closed with 30cm of snow due to land this morning.
Road disruptions
SH94 Te Anau to Milford was closed overnight due to snow but reopened at about 7.45am.
SH73 near Porters Pass was closed to towing vehicles and chains were essential but it has since reopened ao all vehicles. NZTA Waka Kotahi says motorists should still take care.
SH73 SPRINGFIELD TO CASTLE HILL, PORTERS PASS, CANTERBURY - SNOW WARNING - UPDATE: 6:30AM The road is now OPEN to all vehicles. However, please continue to take extra care on this route. ^SM https://t.co/sbq4lrTmYL
— Waka Kotahi NZTA Canterbury & West Coast (@WakaKotahiCWC) August 2, 2021
Motorists using SH1 Rangitata/Hinds are being warned to take extra care after reports of surface flooding in the area.
A strong wind warning is in place for SH7 Hanmer turnoff to Springs Junction.
"Extra care is required by those driving high-sided vehicles and motorcycles until conditions improve," an NZTA Waka Kotahi spokesperson said.
The Queenstown Lakes District Council is asking motorists to drive to the conditions this morning.
A spokesperson said snow has fallen on the Crown Range overnight and it is very icy. Chains are to be carried when driving on the road.
They said there has also been snow on the Lindis Pass, with more to come.
"The road is currently cleared and gritted. Please carry chains and know how to use them, if you're headed that way.
"For the rest of us, overall, mild temperatures this morning with wet roads in the Whakatipu basin. The temperatures are colder around Arthurs Point and Malaghans Rd. In Wānaka, we have mild temperatures with wet roads."
64mm of rain has fallen on the Christchurch Akaroa Highway as well as 24mm in central Christchurch this morning.
The Christchurch Travel Information Team is warning motorists to take extra care, especially those on bikes or motorcycles "as some of the wind gusts we have been getting are very strong".
Surface flooding has caused a lane drop just before the Sockburn Overbridge and a spokesperson said there is a considerable tailback of traffic due to this.