Environment Canada has issued a heat warning for Toronto and southern Ontario for the first weekend of July 2025, with temperatures potentially feeling hotter than 40 degrees Celsius due to high humidity. The heat is accompanied by a risk of scattered thunderstorms, with heavy, moist air expected to trigger severe weather including large hail, heavy rain, damaging wind gusts, and localized flooding in parts of southern Ontario and Quebec on Sunday. The heat warning for southern Ontario is expected to end by the evening of July 6. Meanwhile, Greece is experiencing a four-day heatwave starting July 6, with temperatures reaching up to 42 degrees Celsius and localized thermal camera readings in Athens exceeding 50 degrees Celsius. The heatwave has prompted warnings from local authorities, including the Risk and Crisis Management Committee of the National and Kapodistrian University of Athens. Additionally, a strong heatwave is forecasted for mid-July in France.