Environment Canada issues rainfall, snowfall warnings for parts of B.C.

Snowbanks line the Trans-Canada highway at Rogers Pass on Wednesday, March 4, 2015. (Jeff Bassett / THE CANADIAN PRESS)

Environment Canada says heavy rain and snow will hit separate regions of British Columbia on Friday, promising to make travel difficult for many this weekend.

The weather office issued a rainfall warning Friday for western Vancouver Island, where between 100 millimetres and 120 millimetres are expected to fall before midnight.

Forecasters warn that "a robust and rain-laden frontal system" is moving down the B.C. coast, bringing significant precipitation to the region.

"The heaviest rain will ease off after midnight as the frontal system passes through," the warning says.

Drivers are cautioned that heavy downpours can cause hazardous flash flooding, reduced visibility and pooling water on roadways. Washouts can commonly occur near rivers, creeks and culverts, Environment Canada added.

The weather office urges travellers to slow down, watch for taillights and be prepared to stop at a moment's notice.

Snowfall warnings are also in effect in parts of the B.C. Interior, including along the Trans-Canada Highway from Eagle Pass to Rogers Pass.

Environment Canada forecasts up to 30 centimetres of snow could accumulate over higher elevations before Saturday morning, while lower elevations can expect up to 15 centimetres of new snow.

"Surfaces such as highways, roads, walkways and parking lots may become difficult to navigate due to accumulating snow," Environment Canada says.

"Rapidly accumulating snow could make travel difficult over some locations. Visibility may be suddenly reduced at times in heavy snow."