Definition: A tropical storm is a tropical cyclone with maximum sustained winds of at least 34 knots (39 mph or 63 kph). Tropical storms are given official names once they reach these wind speeds. Beyond 64 knots (74 mph or 119 kph), a tropical storm is called a hurricane, typhoon, or cyclone based on the storm location. A tropical cyclone has a defined cyclonic rotation and severe thunderstorms around a central low-pressure zone. A tropical cyclone is one step above a tropical depression, but a step below a hurricane in terms of intensity.
Also Known As: Tropical weather, TS