Torrential rains swamped the nation’s capital Monday morning, causing massive road and rail delays, knocking out power for thousands — and flooding the White House basement.

Authorities urged commuters to stay off roads throughout greater Washington until 11:15 a.m. as the region was under a flash flood warning, the Washington Post reported.

Amtrak suspended trains traveling south of Richmond, Virginia, because of the severe weather, and it was unclear how long the delays would last.

Power company Pepco said about 3,000 customers were without juice in DC and neighboring Montgomery and Prince George’s counties.

In northern Virginia, flash flooding caused another 3,000 Dominion Energy customers to lose power, the paper reported.

In downtown Washington, the White House basement flooded as heavy downpours drenched the district.

Part of Constitution Avenue in northwest Washington was closed because of high standing water.

People climbed atop cars along Canal Road after they got stuck in floodwaters, and were later rescued or swam to safety.