Prepare for a sharp drop in temperatures as a colder air mass settles into the region following the passage of a cold front. Temperatures Friday afternoon ranged from about 9 C to 14 C across the region, but conditions are expected to cool rapidly overnight, with temperatures nearing the freezing mark by Saturday morning, according to CTV News London’s Reta Ismail. “We’re going to get close to that freezing mark overnight,” Ismail said. The colder air follows a large low-pressure system that brought overnight rainfall to parts of southwestern Ontario. While the rain is expected to taper off later Friday evening, Ismail said some lake-effect showers developing off Lake Huron could affect areas between about 6 p.m. and 9 p.m. The more significant change, she said, will be the arrival of strong northwesterly winds and a noticeably colder air mass. “The real big story with this one is the colder air and the strong gusty northwesterly winds that are going to start to build this evening and into tomorrow,” said Ismail. North winds of 20 to 40 km/h are expected Friday evening, contributing to a chilly start to the weekend. Overnight temperatures are forecast to fall to around 1 C before rebounding under sunny skies Saturday. Despite abundant sunshine, temperatures are expected to remain below seasonal norms. “We’re forecasting a high of 10 degrees and with that chilly northwesterly wind, it will actually feel close to about 7 or 8 degrees tomorrow,” Ismail said. The cooler conditions are expected to be short-lived. High pressure moving into the region will bring mainly sunny skies through the weekend, while temperatures should gradually return to seasonal levels from Sunday through Wednesday.
