Environment Canada has forecast potentially heavy rain for today followed by significant snow early Friday.
Rain began last night ahead of an approaching low pressure system. This rain will then continue into Thursday and become heavy at times. Total rainfall amounts of 15 to 25 mm are likely, said an announcement.
By Thursday evening or Thursday night, the rain is expected to change over to snow after the passage of a strong cold front. Several centimetres of snowfall accumulation will be possible Thursday night through Friday morning, which is Christmas morning, Environment Canada said.
Locally significant accumulations may cause hazardous driving conditions into Saturday morning.
There remains considerable uncertainty as to the exact track of this low pressure system and the timing of the changeover from rain to snow. This will ultimately affect how much snow may fall at any particular location, it said.
Motorists should be prepared for deteriorating winter driving conditions in areas that receive snow from Thursday evening through Friday morning.
25-30 mm rain: CLOCA
The Central Lake Ontario Conservation Authority has advised rainfall of 25-30 mm on December 24. Precipitation is expected to shift to flurries in the evening and continue into the following couple of days.
The rainfall combined with frozen ground conditions could result in increased runoff causing higher than normal water levels and flows in our streams, especially in the vicinity of culverts and bridges. No flooding is anticipated but will be monitored.
The Central Lake Ontario Conservation Authority is asking all residents to stay away from all watercourses, shorelines, and structures such as bridges, culverts, and dams. Elevated water levels, fast flowing water, and slippery conditions along stream banks and Lake Ontario shorelines continue to make these locations extremely dangerous. Please remind children of these dangers.
This Water Safety Statement will be in effect through Saturday December 26, 2020, or until further notice. The Central Lake Ontario Conservation Authority will continue to monitor the conditions of the streams and will provide updates as required.