HOUSTON - The numbers coming in show the amount of rain dumped by Hurricane Harvey in the past four days is equal to a year's worth.

The storm has been downgraded to a tropical storm.

Thirty thousand people were in shelters Monday morning.

The flooding is expected to expand. According to the National Weather Service, rain may continue into next week.

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Houston's mayor, Sylvester Turner, finds himself defending the decision to not order an evacuation.

"I want to thank those thousands and thousands," he said, "in fact millions of Houstonians who heeded the advice and did not get on the road."

FEMA also said the area is not out of the woods.