The torrential downpour that caused flash flooding and left some motorists stranded this morning is the heaviest July 8 rainfall for 148 years, according to National Weather Service meteorologist Andrew Snyder. The NWS recorded 3.3 inches of rainfall in just one hour at National Airport, and 3.41 inches in a three-hour period.

The previous record was 2.16 inches of rainfall on July 8, 1958.

This morning’s rain is also in the top ten heaviest July rainfall recorded in the D.C. area in nearly 150 years.

Snyder says that the NWS is still digging into the data to understand the rarity of this today’s rainfall, but he notes that today’s showers came down with “exceptional intensity.”

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The storm let loose about 6.3 inches of rain in Frederick, Maryland and 4.5 inches in Arlington, according to the Associated Press.

A United States Geological Survey river gauge at Four Mile Run stream in Alexandria recorded a discharge of 8,750 cubic feet of water per second—that’s almost four million gallons of water gushing through the stream’s channel per minute.

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But Four Mile Run isn’t the only place that water was gushing this morning – there were reports of waterfall-like leaks at the Virginia Square Metro station and flooding in some parts of the White House basement.

The National Weather Service has issued a rare “flash flood emergency,” through 11:15 a.m. and a flash flood warning remained in effect until mid-afternoon. A flood warning remains in effect until 6 p.m.

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Dozens Of People Had To Be Rescued Amid Emergency Flash Flooding