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Pedestrians try to stay dry in Miami Beach, Florida, Wednesday as rain floods the area.
More than 3 million people in South Florida face the risk of dangerous flash flooding early Thursday morning as heavy rainfall continues to pummel large metro areas, already flooding some roads and forcing school closures.
Parts of Miami-Dade County could see severe, life-threatening flooding, the National Weather Service warned, issuing a flash flood warning for northern and central parts of the county. The Miami and Fort Lauderdale metro areas are under the warning until 6 ET Thursday, according to the local National Weather Service.
“Drainage will be difficult in many coastal areas due to high tides. Flooding is underway or expected to begin shortly,” the weather service in Miami warned.
In addition to the 2 to 4 inches of rain that has already soaked the region, 1 to 4 inches of rain is possible in places where the flash flood warning is active.
Southeast Florida is facing the brunt of the battle, with rainfall expected to approach double digits. Areas around Fort Lauderdale, Miami and the southwest Florida Keys could see 48-hour rainfall approaching 10 inches.
Broward County Public Schools canceled classes and closed administrative offices Thursday due to safety concerns, the district said on its website.
Meanwhile, in Lauderdale Lakes, located in Broward County, gusts toppled a tree and destroyed two cars, CNN affiliate WSVN reported Wednesday.
Spiro Marchelos, the owner of Anglers Beach Cafe, gave his employees time off due to the conditions.
“It’s a loss of revenue, but we have no choice,” he told the magazine. “The weather is bad and people don’t come to the beach today. It is windy, raining and the streets are flooded.”
As of Wednesday evening, more than 20,000 homes and businesses were without power in Florida, according to the outage-tracking website Poweroutages.us.
A moderate risk of excessive precipitation – Level 3 out of 4 – is in place Wednesday for Southeast Florida. Rainfall amounts of 1 to 3 inches per hour are possible in the heaviest downpours, according to the National Weather Service in Miami.
As of Wednesday night, Miami had been drenched with 6.73 inches of rain in the previous 24 hours, while Hollywood received 5.62 inches and Fort Lauderdale saw 4.2 inches of rainfall in roughly the same time period, according to preliminary reports from the National Weather Service.
This comes after a bout of heavy rain already drenched some areas on Tuesday, setting the region up for trouble ahead of the more widespread event on Wednesday and Thursday. This has left the earth with less ability to absorb excess water thereby increasing the flood threat.
Parts of Palm Beach County and Broward County — where Fort Lauderdale is located — so 3 to 6 inches of rain Tuesday and more another 8 to 10 inches through Thursday. Three-day rainfall totals of more than a foot are not out of the question in these areas.
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Fort Lauderdale has already had an abnormally wet year, and this week’s rain will likely be enough to push the city into record territory. As of Wednesday morning, the city had only recorded 100 inches of rain this year back for its wettest year ever – 102.36 inches in 1947.
The violent rainfall rates and accumulation totals through Thursday across southeast Florida will lead to “a higher likelihood of flash flooding concerns in the urban corridor down into the Florida Keys north of Marathon,” according to the Weather Prediction Center.
Saturated soil and ongoing king tides may slow water from receding in coastal communities that flood this week.
CNN meteorologists Derek Van Dam and Robert Shackelford contributed to this report.