The city of San Diego has been working for the last several days to prepare for Thursday evening's storm.
Thursday afternoon was no exception.
“At 1 p.m., stormwater staff, they closed the intersection here at Avenida Del Rio and River Walk Drive right next to Fashion Valley Mall,” Ramon Galindo, senior public information officer for the city of San Diego, said.
It happened just as holiday shoppers were getting the last of their Christmas gifts.
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“It is kind of last minute, should’ve known it was gonna be kind of crazy,” Mindy Bunch, a holiday shopper, told NBC 7.
The closure may have caused an inconvenience for drivers, but it was a move with safety in mind.
“We really want people to adhere to these warnings,” Galindo said. "Safety is really the top priority. Don’t drive through these flood waters, and people could potentially get ticketed if they do cross through these road closures.”
Dr. Patrick Abbott, professor emeritus of geology at San Diego State University, explained why Mission Valley and Fashion Valley are so flood-prone.
“In a rural area, water, rainfalls, mostly soak into the ground. Some runs off on the surface, but for every roof that’s built, for every bit of pavement that’s laid down, that’s that much water that can’t go into the ground, so it runs off and runs off fast,” Abbott said.
According to Abbott, urbanization increases urban floods.
"What we see in many cities is that their peak flood height can be up to four times higher than they were before the urbanization,” Abbott said.
And Fashion Valley is no exception.
“The way that is built, Fashion Valley, Town and Country, they’re supposed to flood,” Abbott said. "In other words, what is the river? It is the parking lot, and if the river is high enough it goes into the buildings.”
That’s why the city is preparing for the possibility of more road closures.
“Depending on how quickly the river level rises up, then we will potentially close other roads here in Mission Valley,” Galindo said.
To find the list of potential closures, visit the city of San Diego's X account here.
The city urged residents to make their own preparations by clearing trash and debris around their storm drains, ensure trash cans are 2-3 feet away from the curb and to turn off irrigation amid the storm. Residents were also urged to use sandbags if necessary.
Sandbags without sand could be obtained with a limit of 10 per resident or business at the following city of San Diego locations Monday through Friday from 1 to 7 p.m.:
Council District 1 - Pacific Beach Recreation Center, 1405 Diamond St.
Council District 2 (inland) - North Clairemont Recreation Center, 4421 Bannock Ave.
Council District 2 (coastal) - Robb Field Athletic Area, 2525 Bacon St.
Council District 3 - Golden Hill Recreation Center, 2600 Golf Course Drive.
Council District 4 - Martin Luther King Jr. Recreation Center, 6401 Skyline Drive.
Council District 5 - Scripps Ranch Recreation Center, 11454 Blue Cypress Drive.
Council District 6 - Standley Recreation Center, 3585 Governor Drive.
Council District 7 - Allied Gardens Recreation Center, 5155 Greenbrier Ave.
Council District 8 - San Ysidro Community Activity Center, 179 Diza Road.
Council District 8 - Southcrest Recreation Center, 4149 Newton Ave.
Council District 9 -City Heights Recreation Center, 4380 Landis St.
