Some cars had to be pushed along flooded streets when heavy rains flooded parts of Miami on Aug. 1. (The Washington Post)

During the afternoon hours Tuesday, torrential rain drenched parts of Miami and Miami Beach. Four to seven inches of rain fell in a matter of a few hours before and during the evening rush, causing extensive flooding and gridlock.

Cars floated on the curbs, and neighbors helped push stranded motorists down the street. Parked cars on flooded roads bobbed in the wake as larger trucks and SUVs passed.


Five-hour radar loop spanning the heaviest rain during the afternoon hours. (Brian McNoldy)

This region is no stranger to tropical downpours, but this amount of rain falling in a short time will create flash flooding just about anywhere. And in some ways, because it is so low-lying, this region is more vulnerable to flooding than many as it depends on storm drains being able to drain into nearby Biscayne Bay. Unfortunately, in this case, the water had nowhere to go as the heaviest rain came as the tide was rising. It couldn’t drain until the tides began to go back down hours later.

Year by year, as the average water level increases due to sea-level rise, high tides become more of a problem — either by reducing the ability of storm drains to function or by actually bringing salt water up onto the streets when they’re very high.

For now, the latter is typically only a problem around the full moons in September, October and November, colloquially known as the “King Tides.”  But as sea level continues to rise, the baseline increases and flooding (both freshwater and saltwater) will become more and more common.


Time series of cumulative rainfall (red line) and tide cycle (blue line). (Brian McNoldy)

While some parts of Miami Beach have giant pumps installed to help remove water from the streets, they don’t yet have backup generators. Tuesday’s storms came with an amazing amount of lightning and knocked out power for a while, rendering those pumps useless during the highest rain rates.

However, thanks to sandy soil and the tides going back down after the rain, it didn’t take too long for the water to drain away. But the damage was done to vehicles, houses and businesses. And although that rainfall total in Miami Beach was impressive, it wasn’t a daily record — that was set June 5, 2009: 9.3 inches.

Here are some more photos and video from the event. (WARNING: This flood was obviously absurd and some of the locals use profanity to express their astonishment in these videos.)

#SouthBeach August 1st 2017

Posted by Ashley Diaz on Tuesday, August 1, 2017