UPDATE (1.47pm):
The site has now been cleared following a truck and motorcycle accident in Katoomba.
The accident occurred on the Great Western Highway at Rowan Lane on Thursday afternoon.
All westbound lanes have now re-opened and traffic flow is returning to normal.
1.37pm:
There are traffic delays in Katoomba following a serious accident on Thursday afternoon.
The accident, involving a truck and motorcycle, occurred on the Great Western Highway at Rowan Lane.
One westbound lane is closed to traffic.
Emergency services personnel are at the scene.
Motorists are advised to reduce speed and exercise caution in the area.
It is the second major accident to occur on the Great Western Highway on Thursday.
A female motorcyclist remains in a critical conditions following a crash on the highway at Lawson earlier in the day.
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