[20211013]IN11775_2021飓风展望和2020年飓风季节回顾.pdf

2021 Hurricane Outlook and Review of 2020 Hurricane Season October 13, 2021 The potential for widespread storm destruction to the United States underscores the value of timely tropical cyclone forecasts. The National Oceanic and Atmospheric Administration (NOAA) is responsible for issuing tropical cyclone forecasts, including track, intensity, storm surge, and rainfall. NOAA defines a tropical cyclone as a “rotating, organized system of clouds and thunderstorms that originates over tropical or subtropical waters and has a closed low-level circulation.” According to NOAA, tropical cyclones include Tropical depressionsmaximum sustained winds of 38 miles per hour (mph). Tropical stormsmaximum sustained winds of 39-73 mph. NOAA typically names a storm once it reaches this strength. Hurricanesmaximum sustained winds of 74 mph, corresponding to a category 1 or 2 on the Saffir-Simpson Hurricane Wind Scale. Hurricanes are called typhoons or cyclones in other parts of the world. Major hurricanesmaximum sustained winds of 111 mph, corresponding to a category 3, 4, or 5. NOAA releases seasonal hurricane outlooks relevant to the United States, including the north Atlantic, eastern Pacific, an