News Frost advisory in effect SHARE ON: Patrick Grapes, contributor, Wednesday, May. 15th, 2019 Frost on a windshield. (stock photo) You may want to get those gardens covered up. A frost advisory is in effect for the Haliburton, Minden, Southern Haliburton County, Oxtongue Lake, Fort Irwin, and Northern Haliburton County areas. Environment Canada says clearing skies this evening will allow temperatures to fall to the freezing mark overnight tonight. Frost advisories are issued when temperatures are expected to reach the freezing mark during the growing season, leading to potential damage and destruction to plants and crops.