Dallas (CNN) -- Severe weather hit the Houston area Monday, flooding streets and homes and leaving thousands of people without power, emergency officials said. Torrential rain fell across the area, causing flash flooding that left streets and highways impassable and submerged some vehicles. "We have a lot of roadways closed, and some evacuations are going on," said Alan Spears of the Fort Bend County office of emergency management. In the city of Richmond, rescues were conducted by boat and on foot. Spears said he believes a tornado touched down in the area. "We had 7,000 people without power in the county," he said.
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NEW: More than 4 inches fall at Houston Hobby Airport, setting a record
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National Weather Service to investigate possible tornado touchdowns
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Houston has conducted 20 to 30 high-water rescues, another official says
The rain was falling so hard and fast in @placeholder that the weather service recorded 1.6 inches in just 10 minutes.