Summer’s end means the precipitation we could see from this year’s potentially record-breaking “Super” El Niño is just around the bend.

The National Oceanic and Atmospheric Administration’s Climate Prediction Center released its September El Niño update Thursday, saying there is a greater than 90% chance of a very strong event in the Northern Hemisphere during this fall and winter.

Chandler Price, a meteorologist at the San Diego office of the National Weather Service, said just because an El Niño is evident, it doesn’t automatically mean an unusually wet winter. Price says he and other researchers need to see a weather pattern develop before they can provide a forecast.

If the El Niño brings increased rain to the coast, Price said the region could begin to see winter storms as early as late September and they could last through April.

While the amount of rain San Diego will get this year is still up in the air, high tides and large ocean swells will hit the coastline. In preparation, the city of San Diego began its annual installation of sand berms on City beaches and the Mission Bay shoreline Thursday to help protect against flooding. They will take several weeks to install and are expected to be completed by early November.

Another figure NOAA released is a 75% chance this El Niño will exceed the strength of previously recorded events dating back to the 1950s when the agency began collecting data on El Niño weather patterns. Price said that’s actually a good chance of breaking the historical record.

There have been six strong El Niños on record. But strength and precipitation don’t go hand in hand, something scientists are making clear to the public.

Price pointed out that the strong events with the highest precipitation as well as those events with the lowest precipitation both had similar scores on the index used to classify them. 

Looking at the past data, there is an 83% chance that this El Niño, if it comes in among the strongest on record, will result in more precipitation than we would typically see, Price said.

So, should we sound the alarm?

In spite of the 1972 tune “It Never Rains in Southern California,” Price says San Diegans should stay vigilant for flooding every winter, not just during an El Niño.

“The good thing about this is that it is encouraging new conversations about how you prepare for this on a personal or structural level,” he said.

While widespread flooding is still not a guarantee, Price says he has a lot of confidence in the fact that Southern California will see coastal erosion and coastal flooding. Daniel Swain, an associate researcher at UC Agriculture and Natural Resources and a research partner at the National Center for Atmospheric Research, agrees.

“There will be significant coastal flooding that will get worse from here… How bad it gets will depend [on] whether we get alignment of the king tides, the peak of a coastally trapped Kelvin wave and a big storm event, Swain said.” 

“It could happen, and it could get pretty darn bad. That would paralyze a lot of the low-lying infrastructure.”

The Kelvin waves Swain mentioned are just extremely large, slow-moving waves that do not break. They’re important to note because they bring higher water levels than we would typically see.

These elevated water levels along with high surf, Price said, have already contributed to visible erosion, and could likely be something that will continue through the winter. And as sea levels are expected to rise by a foot in the next couple of decades, the discussions El Niño has brought to coastal communities on how to adapt is something, Price said, that will likely need to continue outside of these events into the future.

“[Elevated surf days have] already done a lot of damage and erosion,” Price said. “King tides today might look like what every day looks like in 100 years. So I think it’s a great conversation to be having.”