The first snow-related weather advisory has been issued for south Niagara.
The south end of the Region is under a snow squall watch with heavy snowfall possible tomorrow night and Wednesday.
10 to 15 cm of snow is possible with peak snowfall rates of 2 to 5 cm per hour.
Officials say poor visibility is expected as the lake effect snow squalls over Lake Erie, could move inland overnight Tuesday, and may become mixed with rain Wednesday afternoon.
For the rest of Niagara, 2-4 centimetres of snow could fall.