Southern Ontario: Winter Weather Hazards Outlook for Monday, December 27, 2021

Forecast Discussion

A messy system is expected to move into Southern Ontario starting Monday morning. It appears that it will begin as some light to moderate snowfall to those north of Lake Erie. The Windsor and Chatham-Kent region should primarily see just rain although could be mixed at times during the morning. This snow won’t be too impactful with general totals ranging from 2-4cm (a few locations may pick up near 6cm and others might see only a trace). Due to the nature of this system, we can’t issue a precise snowfall accumulation map as it will be extremely variable depending on elevation and temperatures.

The main concern with this precipitation is during the afternoon and evening where we will see the snow begin to switch over to some freezing rain or drizzle. This risk is quite extensive including Sarnia, London, K/W and into the GTA. It won’t be particularly heavy, but it will linger for several hours. Expect some icy road conditions for your Monday evening commute. A thin layer of ice accretion on surfaces may result in isolated tree damage or power outages, but these should be very limited as the freezing rain will be very light.

The risk of freezing rain will shift into Central and Eastern Ontario later in the evening and overnight Monday. The Ottawa region should remain predominantly snow but they likely won’t see anything more than a few centimetres from this system.