Original: Tropical storms have one-minute maximum sustained winds of at least 39 mph (34 knots, 17 m/s, 63 km/h), while hurricanes have one-minute maximum sustained exceeding 74 mph (64 knots, 33 m/s, 119 km/h).
Simplified: An Atlantic hurricane refers to a tropical cyclone that forms in the Atlantic Ocean usually in the Northern Hemisphere during the summer or autumn, with one-minute maximum sustained winds of at least 74 mph (64 knots, 33 m/s, 119 km/h).