High surf, coastal flooding and beach erosion will remain concerns Tuesday along the Southern California coast as swells from Hurricane Polo and Tropical Storm Odalys continue to affect the region, while forecasters warn of a potentially dangerous heat wave this weekend.
A coastal flood advisory and a high surf advisory will remain in effect until 5 p.m. Tuesday for Los Angeles County beaches, according to the National Weather Service.
In Orange County, a coastal flood advisory will remain in effect until 5 p.m. Wednesday.
Southerly swells from Polo and Odalys will continue to affect the region through Tuesday, with Polo expected to produce the more significant swell from the south-southeast, according to the NWS.
“This swell timing will line up with very high tides … in the late morning hours,” forecasters said. “Some south-facing shores are more vulnerable because of the lingering erosion effects from Hurricane Marie earlier this month.”
Surf along Los Angeles County beaches is expected to peak at 4 to 7 feet Tuesday.
High tides are expected to reach around 7 feet in the late morning Tuesday, nearly a foot above astronomical tides due to the ongoing effects of El Nino, according to the NWS.
“While this swell is slightly smaller than the swell from Marie, there is still significant concern of Coastal Flooding over vulnerable south-facing beaches,” forecasters said.
Areas of greatest concern include Avalon, Long Beach and Malibu. The weather service said a “reasonable worst-case scenario” would produce impacts similar to those from Hurricane Marie earlier this month, although the most likely outcome would be less severe.
Avalon could be particularly vulnerable because Polo’s swells are arriving from a more southeasterly direction than those from Marie, leaving the area more exposed, according to the NWS.
South-facing beaches could experience shallow seawater flooding of low-lying walkways, parking lots and roads, along with significant beach erosion. Very localized damage to structures is possible in the most vulnerable areas, forecasters said.
Los Angeles’ Emergency Management Department issued an alert Friday warning residents to prepare for the impacts, including an increased risk of drowning from widespread and very strong rip currents.
Residents in areas prone to coastal flooding were advised to obtain ready-to-fill sandbags from Los Angeles Fire Department stations and review information on proper sandbag placement at lafd.org.
The weather service warned that a potentially dangerous heat wave could begin developing Friday and continue through next week as high pressure builds over the region and offshore pressure gradients increase.
Temperatures are expected to begin climbing Friday, with about 3 degrees of warming each day through Oct. 5. Forecasters said warmer valley areas could eventually reach 105 to 110 degrees, while downtown Los Angeles and other inland coastal areas could reach 100 to 104 degrees and coastal areas could reach 85 to 98 degrees.
Before the heat wave develops, a low-end Santa Ana wind event is expected Tuesday, with northeast winds mostly confined to the mountains and generally remaining below 35 mph. Temperatures are expected to rise at least 5 degrees along the coast and 10 degrees or more elsewhere before a slight cooldown Wednesday and Thursday.