Stratford News Snow Squall Warning Issued for Perth and Huron Counties. SHARE ON: Gregory Rosser, contributor, Thursday, Nov. 9th, 2017 Photo: Supplied Environment Canada has upgraded its snow squall watch to a warning. The national forecaster is calling for anywhere from 10 to 15 centimetres of snow in some areas. The warning has been extended to London-Middlesex and Grey-Bruce. Drivers should expect poor visibility and rapidly changing conditions on our roads continuing into tonight and tomorrow morning.