SD&G, Ont. — The Cornwall-area and portions of Eastern Ontario are under a severe thunderstorm watch. Environment Canada issued the advisory at 4:41 p.m. this afternoon saying conditions are favourable for possibly dangerous thunderstorms to develop. It’s been hot and muggy this afternoon leading to very unstable air. The advisory covers Morrisburg, Long Sault, Winchester and Newington. The thunderstorms could produce strong wind gusts, large hail and torrential rain. The Ottawa Valley was under similar advisories earlier this afternoon but those have since been lifted. The forecast is calling for more showers tonight and through most of the day tomorrow.