If three occurrences constitute a trend, then catastrophic storms—that is, Category 4 or 5 storms on the Saffir-Simpson Hurricane Wind Scale—are the trend for Atlantic hurricanes in 2017. One day after forming as a tropical depression, Potential Tropical Cyclone Fifteen strengthened rapidly, becoming Hurricane Maria with wind speeds of 120 km/h (75 mi/h) on September 17, according to the U.S. National Hurricane Center. By late afternoon on September 18, Maria became the third Category 4 storm of the season, with maximum sustained winds of 209 km/h (130 mi/h). Category 4 storms have wind speeds of 209 km/h (130 mi/h) or higher and may leave affected areas uninhabitable for months. See also: Atlantic Ocean; Cyclone; Extreme weather events; Hurricane; Hurricane Harvey (Atlantic, 2017); Hurricane Irma (Atlantic, 2017); Tropical meteorology
When it reached maximum wind speed, Maria began cutting a destructive path through the Caribbean, first making landfall (September 20) on the island of Dominica as a Category 5 hurricane, with wind speeds of 260 km/h (160 mi/h). On September 21, Maria demolished Puerto Rico from south to north as a Category 4 storm with wind speeds of 240 km/h (150 mi/h), dumping as much as 100 centimeters (40 inches) of rain in places and causing extreme flooding. Electrical power was knocked out across the island, as was most phone service and drinking-water infrastructure, creating a crisis for over 3 million people that live in the U.S. territory. Maria next skirted the Dominican Republic, largely sparing the island from major damage, and then headed for the Turks and Caicos Islands. On September 22, Maria passed over the Turks and Caicos as a Category 3 storm, with maximum sustained winds of 201 km/h (125 mi/h). From there, Maria weakened to a Category 1 storm as it moved into the open waters of the Atlantic and became a tropical storm off the coast of North Carolina, where it picked up speed and headed east-northeastward across the North Atlantic, according to the National Hurricane Center. See also: Telephone service; Water supply engineering; West Indies
