Issued at 15:35 Friday 13 April 2018. Significant ice build-up due to freezing rain is expected or occurring. A moisture laden low pressure area over the Central Plains States will amble slowly towards the lower Great Lakes this weekend. As the low gets closer, brisk northeasterly winds will pump in cold arctic air, forcing temperatures to fall to near or below the zero degree mark on Saturday.
Rain associated with this low will switch to freezing rain on Saturday morning, and will likely persist for a number of hours into Saturday evening. Freezing rain may become mixed with or turn over to ice pellets at times, with some areas receiving a few centimetres of the ice pellet mess. Some snow is possible especially in the Belleville to Kingston areas.
Freezing rain is expected to end for a few hours on Saturday evening, with patchy freezing drizzle likely during the lull. However, as the low gets close to Southern Ontario Saturday night, freezing rain is expected to move back in, and may persist well into Sunday before changing over to rain. Some uncertainty exists as to the time the precipitation switches over to rain on Sunday. Enough rain may fall later Sunday into Sunday night for some flooding to be an issue to deal with then.
Ice build up of 10 to 20 mm appears quite likely across the region by Sunday morning. Ice accretion may be considerably less in areas very close to Lake Ontario as temperatures there may actually remain very close to the freezing mark.
