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A Timeline of Hurricane Harvey's Development

Aug 26, 2017

(CORPUS CHRISTI, Texas) — Hurricane Harvey made landfall in Texas on Friday night as the strongest hurricane to hit the U.S. in more than a decade. By Saturday morning, it had dumped 18 inches (half a meter) of rain on some areas, and forecasters warned that it could cause catastrophic flooding in the coming days.

Here is a timeline of key moments in the storm's development:

— Aug. 17, 4 p.m., Tropical Storm Harvey is named, six hours after the National Hurricane Center in Miami issues a potential tropical cyclone for several small Caribbean islands.

— Aug. 19, 4 p.m., Moving westward between the northern coast of South America and the larger Caribbean islands, Harvey is downgraded to a tropical depression, with maximum sustained winds of 35 mph (56 kph). Six hours later, it is further downgraded to a tropical wave.

— Wednesday, 10 a.m., Harvey regenerates into a tropical depression about 535 miles (860 kilometers) southeast of Port O'Connor, Texas, with maximum sustained winds of 35 mph (56 kph).

— Thursday, 1 p.m., After quickly strengthening over the course of a day, Harvey becomes a hurricane, with maximum sustained winds of 85 mph (140 kph). It is about 325 miles (525 kilometers) southeast of Port O'Connor, and Texas coastal communities in its path are urged to complete their preparations. By midnight, it is upgraded to a Category 2 hurricane and is 220 miles from Port O'Connor, with sustained maximum winds of 100 mph (160 kph).

— Friday, 2 p.m., Harvey is upgraded to a Category 3 hurricane, with sustained maximum winds of 120 mph (195 kph). It is centered about 75 miles (120 kilometers) southeast of Corpus Christi. By 6 p.m., Harvey is a Category 4 storm just 45 miles from the city, with maximum sustained winds of 130 mph (215 kph).

— Friday, 10 p.m., Harvey makes landfall as a Category 4 hurricane when the eye of the storm comes ashore between Port Aransas and Port O'Connor, two communities on a spit off the coast of mainland Texas near Corpus Christi.

— Saturday, 2 a.m., Harvey is centered about 15 miles inland and is weakening as it slowly passes over land. It has been downgraded to a Category 3, with maximum sustained winds of 115 mph (185 kph). Two hours later, it is downgraded further to a Category 2.

— Saturday, 5 a.m., With maximum sustained winds of 90 mph (150 kph), Harvey is downgraded to a Category 1 storm. Forecasters warn of potentially catastrophic flooding in the coming days.

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