Persistent snow squalls are expected to develop. Under the snow squall bands, visibilities will be significantly reduced due to the heavy snow combined with blowing snow, and snow will quickly accumulate.
Snow squall watch in effect for:
Sault Ste. Marie – St. Joseph Island
Searchmont – Montreal River Harbour – Batchawana Bay
Much colder air will return to northern Ontario this afternoon. This northwest flow of cold air rushing over the relatively warm waters of Lake Superior will generate snow squalls. Snow squalls are expected to develop late this afternoon and persist into Monday evening. Local snowfall rates of 10 to 15 cm per 12 hours are possible under the strongest snow squalls.
Snow squalls cause weather conditions to vary considerably, changes from clear skies to heavy snow within just a few kilometres are common. Visibility may be suddenly reduced at times in heavy snow.