The precipitation was expected to shift to rain on Sunday as temperatures warmed.
The rain and thunderstorms in Mid-Michigan this morning will transition to freezing rain and sleet this afternoon and evening as colder air pushes into the area on a strong Northeast wind.
A moisture-laden low pressure area is heading this way, which is expected to force temperatures to fall near the zero-degree mark Saturday.
The weather agency says risky winter driving conditions are expected on untreated roads on the weekend. "Several centimetres of ice pellets are likely during the day".
UPDATE (11:08 a.m. Thursday, April 12): A special weather statement continues for Bracebridge - Gravenhurst, Port Carling - Port Severn, Huntsville - Baysville and Town of Parry Sound - Rosseau - Killbear Park areas.
Scattered rain showers mixed at times with freezing rain in the morning. Small streams and creeks, low-lying and poor drainage areas may see flooding Sunday night through Monday.
An ice buildup up to 15 mm appears likely by late Sunday. It may exceed that in some locales.
The weather agency says southwestern Ontario in particular is facing a "potentially historic ice storm", adding that freezing rain will likely lead to widespread power outages.
Unsafe winter driving conditions are expected on untreated roads Saturday and Sunday, worsened by fallen tree limbs.