Thunder Bay Police are expecting driving conditions to deteriorate Monday afternoon.
The day started with slippery roads because of freezing rain overnight, which turned to snow in the morning.
Road crews have been working to make roads as safe as possible.
Traffic Sergeant Glenn Porter said it seems people are using caution and slowing down, but he said there were four collisions through the morning.
The blast of winter weather also caused a number of closures and service cancellations.
The NorWest Community Health Centres program Living with Diabetes Series from 6-8 pm tonight has been cancelled.
The Thunder Bay District Health Unit cancelled the Vickers Heights Community Centre flu clinic. It was the unit’s last scheduled clinic for 2014.
Officials with the unit advised people can still get the flu shot at the Health Unit on Wednesdays during the immunization clinic, or at local health care providers' offices or pharmacies.
The weather also lead to the cancellation of all school buses in the city, and along rural routes. Schools in the city remained open, but all rural schools were closed for the day.
School buses for the Superior-Greenstone Board, east of Thunder Bay, were also cancelled. Affected communities included Dorion, Nipigon, Red Rock, Greenstone, Terrace Bay, Schreiber, Marathon and Manitouwadge.
As well, Thunder Bay Transit ordered all drivers to pull their buses to the side of the road, until conditions improved.
Transit service resumed after 8 a.m.
Environment Canada issued a freezing rain warning for Thunder Bay this morning. It ended just after 9 a.m.
However, Environment Canada called for rain or ice pellets to change to snow with strong northerly winds later in the day. The total accumulation was expected to be around 5 cm in the city.
Further east, Manitouwadge and Hornepayne were under a freezing rain warning, until just after 1 p.m. Environment Canada says precipitation has changed to snow, with 10 cm expected by this evening and another 5 cm or so expected tonight
Geraldton, Longlac and Nakina areas are under a snowfall warning, with total amounts of about 15 cm expected.
Meteorologist Jeff Coulson said strong northerly wind gusts combined with snow were causing periods of low visibility in areas north of Lake Superior.
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