Hurricanes are massive storm systems with strong winds, torrential rains, dangerous storm surge and tornadoes. They form over the Atlantic Ocean, Caribbean Sea and Gulf of Mexico each year on average during hurricane season, which runs from June 1 through November 30.
Hurricanes begin as low-pressure areas over warm tropical waters. These suck up hot, moist air from the surface of the ocean and spiral inward toward the center of the storm. As this swirling mass of hot, moist air rises, it cools and condenses to create intense thunderstorms and gusty winds. Wind speeds reach 39 mph (63 km/h) and the storm becomes a tropical depression; when winds reach 74 mph (119 km/h), it’s a hurricane.
Once a hurricane reaches land, it slows down and weakens. But even when they lose strength, storms still plow into coastal areas with high winds and storm surge, often for days at a time, dumping many inches of rain. This provides a much-needed influx of moisture, replenishing the very dry soil typical of summer and fall in the eastern United States.
Climate change is making hurricanes stronger, more destructive and slower to dissipate after hitting land. Limiting greenhouse gas emissions and bolstering resilience in coastal communities are key to reducing the risks from future hurricanes.