Ok, they're not entirely harmless (e.g. if you fly into an hailing embedded thunderstorm at low altitude). But overflying one at cruising altitude is 100% safe.
E.g. the plane in this story flew through the eyewall of a hurricane at 1,500 feet. A commercial jet flies at a cruising altitude of up to 45,000 feet.
E.g. the plane in this story flew through the eyewall of a hurricane at 1,500 feet. A commercial jet flies at a cruising altitude of up to 45,000 feet.