It's believed the two girls went for a hike near Buntzen Lake between noon and 2 p.m. PT, but lost their bearings and used a cellphone to call for help around 6 p.m. PT.
Search and Rescue attempted to deploy a helicopter to find the pair, but it was too cloudy to do a drop down rescue. Rescuers are instead hiking in to find them, a trip which will take four hours each way.
It is believed the girls are at Swan Falls, near the northeast tip of the lake. They are not well-equipped to be outside overnight.