Severe thunderstorms tonight may bring heavy rainfall, localized flooding, and strong winds, particularly in areas with a 100% chance of rain. Cities like Oklahoma City, OK, and Austin, TX, are under extreme heat conditions, posing risks of heat-related illnesses. Coastal areas, including New Orleans, LA, may experience thunderstorms with gusty winds and high humidity, increasing the risk of power outages and travel disruptions. Fog in Mt. Washington, NH, could reduce visibility, impacting transportation.