The National Hurricane Center has downgraded Hurricane Harvey from a Category 1 hurricane to a tropical storm.
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But officials say they are still worried about potentially catastrophic rainfall that will continue for days, with more than 40 inches and flash flooding possible even well inland.
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Harvey came ashore Friday along the Texas Gulf Coast as a Category 4 storm with 130 mph winds, the most powerful hurricane to hit the U.S. in more than a decade.
One death has been reported in this hurricane. Authorities say 56-year-old Robert Dean Schoenhals, drowned after his car was swept away by floodwaters caused by thunderstorms that pummeled the region. Crews located his body hours after the accident. A deputy saw Schoenhals try to drive through high standing water on a highway when the car hydroplaned off the road and entered a ditch with deep, rushing water.
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Experts say hurricanes almost always lose strength quickly after making landfall and moving away from the warm waters that fuel their winds. But the danger doesn't end there.
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Harvey is expected to keep slowing and dumping rain through the middle of next week.
Hurricane Harvey has been dumping nearly 3 inches (76.2 millimeters) of rain per hour at times and has left some streets in flood-prone Houston submerged in water.
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Harris County Judge Ed Emmett, the chief administrator of the county that includes Houston, says flooding so far is a "minor issue." He says most of the watersheds are well within their banks "but we're not out of this."
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Forecasters are predicting major flooding in the area by Tuesday. Houston has about 1,700 miles (2735.76 kilometers) of channels that drain to the Gulf of Mexico.
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A handful of freeway service roads and streets and some scattered neighborhoods that normally experience high water in heavy rain have been flooded.
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Houston Mayor Sylvester Turner cautions that although major flooding hasn't happened yet, "that can change."
The Associated Press and CBS News contributed to this report.Â
