You may want to alter your travel plans if you’re heading west this week.

Environment Canada has issued a Winter Storm Watch for parts of Northwestern Ontario covering Dryden, Sioux Lookout, Kenora, Red Lake and Ear Falls areas.

A developing low pressure system is expected to bring heavy and blowing snow starting Wednesday afternoon and will quickly intensify Wednesday evening.

As you go farther east, the snow should change to rain by Thunder Bay and the north shore of Lake Superior.

This heavy snow will continue through Thursday before slowly tapering to lighter snow or flurries Friday afternoon or evening.

The snow will be accompanied by strong winds at times which could result in reduced visibilities due to blowing snow especially on Thursday and possibly Friday.

Total accumulations of 25 to 40 cm are possible by Friday evening however regions in the swath of heaviest snow could see local amounts of up to 50 cm.

Travel is expected to rapidly deteriorate Wednesday evening.

Rapidly accumulating snow could make travel difficult over some locations.

Visibility may be suddenly reduced at times in heavy snow.

Surfaces such as highways, roads, walkways and parking lots may become icy and slippery.

Public Safety Canada encourages everyone to make an emergency plan and get an emergency kit with drinking water, food, medicine, a first-aid kit and a flashlight.