11:42 AM EDT Saturday 29 June 2024 Severe Thunderstorm Watch in effect for: St. Catharines - Grimsby - Northern Niagara Region Severe thunderstorms likely today. Hazards: Wind gusts up to 100 km/h possible. Torrential rain. Risk of a tornado. Timing: This afternoon and this evening. Discussion: Thunderstorms this afternoon have the potential to quickly become severe and generally track eastward. Thunderstorms are generally expected to be isolated early this afternoon, however, a organized line of thunderstorms may develop later this afternoon. Very strong wind gusts can damage buildings, down trees and blow large vehicles off the road. 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 10:50 AM EDT Saturday 29 June 2024 Special Weather Statement in effect for: St. Catharines - Grimsby - Northern Niagara Region Significant rainfall continues today. Hazard: Total rainfall amounts of 30 to 40 mm. Locally higher amounts in thunderstorms are possible. Timing: Through early afternoon. Discussion: Showers, heavy at times, are expected to continue over parts of southwestern Ontario early this afternoon. Embedded thunderstorms could give locally higher amounts. The heavier showers will taper off early this afternoon, but scattered showers with isolated thunderstorms will continue throughout this afternoon and early evening. For information concerning flooding, please consult your local Conservation Authority or Ontario Ministry of Natural Resources and Forestry office. Visit Ontario.ca/floods for the latest details. Heavy downpours can cause flash floods and water pooling on roads. Watch for possible washouts near rivers, creeks and culverts. 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 .