The National Weather Service also cautioned drivers against driving through stretches of high and running water.
"We have a lot of rain falling out of these storms. Heavy rain with the storms not moving very much so they're pretty much stationary and just dropping a lot of rainfall," Sullivan said.
The National Weather Service was initially too busy to respond to comment.
The storm was immediately recorded by onlookers as sheets of rain fell, streets flooded and thunder claps set off many a car alarm in the city.