Medway Road has re-opened after an earlier truck roll-over.
Motorists are advised to allow additional travel time as traffic is slow in the area.
Southern Highlands Police Officer-in-Charge Inspector John Klepczarek said the weather may have played a role in the incident.
“Early indication appears to be the wind has blown the trailer onto its side,” he said.
Investigations are continuing.
Northbound lanes are still closed at Berrima with delays up to 3km.
Drivers are being diverted on to the Old Hume Highway, with traffic slowing at Golden Vale Road.
A truck has rolled over at the intersection of Medway road and Hume Highway in Berrima.
Shortly after 3pm, emergency vehicles responded to the rolled over truck.
Northbound lanes are closed with diversions in place.
According to a NSW ambulance media spokesperson, the driver was uninjured.
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