6:25 PM EDT Monday 20 May 2024 Severe Thunderstorm Watch in effect for: Sarnia - Lambton Conditions are favourable for the development of severe thunderstorms that may be capable of producing strong wind gusts and large hail. Large hail can damage property and cause injury. Strong wind gusts can toss loose objects, damage weak buildings, break branches off trees and overturn large vehicles. Locally heavy rain is also possible. Lightning kills and injures Canadians every year. Remember, when thunder roars, go indoors! Emergency Management Ontario recommends that you take cover immediately if threatening weather approaches. Severe thunderstorm watches are issued when atmospheric conditions are favourable for the development of thunderstorms that could produce one or more of the following: large hail, damaging winds, torrential rainfall. Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to ONstorm@ec.gc.ca or tweet reports using #ONStorm . For more information: ontario.ca/page/be-prepared-emergency . Statements 3:55 PM EDT Monday 20 May 2024 Special Weather Statement in effect for: Sarnia - Lambton Hot and humid conditions expected Tuesday. A hot and humid airmass is moving into southwestern Ontario. Maximum temperatures of 31 degrees Celsius are expected Tuesday with overnight minimum temperatures near 21 degrees Celsius. Slightly cooler temperatures are expected Wednesday as showers and thunderstorms are possible through the day. As a result, the hot and humid conditions are not expected to reach heat warning criteria. These conditions pose a health risk when you are not used to the heat. Everyone is at risk from heat, especially older adults; infants and young children; and people with chronic illnesses. You are advised to 1) drink plenty of cool liquids before feeling thirsty; and 2) keep cool by dressing for the weather and spending more time in a cool place. Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high risk category. Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to ONstorm@ec.gc.ca or tweet reports using #ONStorm .