Southern California is keeping a close eye on the Pacific as a newly formed tropical storm raises the possibility of an unusually wet and potentially hazardous Labor Day weekend.
As of Tuesday morning, September 1, the National Hurricane Center confirmed that Tropical Storm Marie had formed several hundred miles southwest of Mexico. At 8 a.m. MST, Marie had maximum sustained winds of 45 mph and was moving northwest at approximately 9 mph. Forecasters expect the system to strengthen, potentially becoming a hurricane by Wednesday night.
But does that mean a hurricane is actually coming to Los Angeles?
At this point, a hurricane making landfall in Los Angeles is highly unlikely. What is considerably more plausible is that Marie, or moisture and ocean swells associated with it, could affect Southern California during Labor Day weekend.
A Wide Range of Possibilities
The National Weather Service’s Los Angeles/Oxnard office described the Labor Day forecast as unusually uncertain, with possible outcomes ranging from essentially normal weather to tropical rainfall.
Forecast models have offered dramatically different scenarios. One model has shown the tropical system continuing north toward Southern California, while another turns it west and keeps it well away from the state.
The Weather Service’s ensemble forecasts provide a better indication of the probabilities. Only about 5% to 10% of approximately 100 projections showed two inches or more of rain, representing the more significant heavy-rain scenario. Roughly 20% to 30% showed a completely dry outcome.
That leaves the most likely rainfall scenario somewhere in between: light to moderate rain, generally under one inch, if tropical moisture reaches the region. Rain could begin as early as Saturday, although chances currently appear higher from Sunday through Monday night.
The forecast is expected to become clearer as Marie develops and computer models get a better handle on its strength and direction.
Could Marie Actually Reach Los Angeles as a Hurricane?
The distinction between a hurricane reaching Los Angeles and the effects of a hurricane reaching Los Angeles is important.
Southern California’s coastal waters are generally too cold to sustain a tropical cyclone. Hurricanes draw their energy from warm ocean water, and storms traveling north along Baja California typically weaken dramatically as they encounter the cooler Pacific waters off California.
Meteorologists told the Los Angeles Times that even if Marie eventually takes a track toward Southern California, it would very likely weaken below hurricane strength — and probably below tropical storm strength — before reaching the region.
A more realistic scenario would resemble some previous tropical systems that have affected California: a weakening or post-tropical storm delivering substantial tropical moisture, thunderstorms, heavy rainfall and large waves rather than destructive hurricane-force winds.
The National Weather Service currently considers a major heavy-rain event among the less likely possibilities, but it has not been ruled out.
Beaches May See the Biggest Impact
There is considerably more confidence about one potential Labor Day impact: rough ocean conditions.
The National Hurricane Center says swells generated by Marie will likely spread northward into Southern California over the weekend and could produce life-threatening surf and rip currents.
The Los Angeles/Oxnard Weather Service office also reports growing confidence in significant coastal impacts. South-facing beaches could experience high surf and very strong rip currents, particularly Sunday through Monday night.
Timing could make matters worse. Evening high tides are expected to reach approximately 6.5 to 6.8 feet Sunday and around 7 feet Monday. The combination of elevated tides and tropical swell could produce minor coastal flooding and beach erosion, with moderate coastal flooding possible if the largest waves coincide with high tide.
Among the locations particularly susceptible to a south-southeast swell are Catalina Island, Long Beach to Cabrillo Beach, Malibu and Point Mugu.
The Bigger Concern Would Be Rain, Not Hurricane Winds
If Marie does turn toward Southern California, forecasters are more concerned about tropical moisture than hurricane-force winds.
Heavy tropical rainfall can trigger flash flooding, mudslides and debris flows, particularly in mountain communities, deserts and areas recently affected by wildfires.
Climate scientist Daniel Swain told the Los Angeles Times that even in a scenario where the system approaches Southern California, damaging hurricane winds are not the primary concern. Instead, a decaying tropical system could bring large amounts of moisture, showers, thunderstorms and dangerous coastal conditions.
Southern California experienced a recent example with Hurricane Hilary in August 2023. Hilary weakened before reaching California but still generated extensive rainfall and flooding, particularly in the Coachella Valley, San Bernardino County and Death Valley.
Hurricanes in Los Angeles Are Extremely Rare
California’s geography and ocean temperatures make direct tropical cyclone strikes exceptionally unusual.
One of the most significant modern events occurred in September 1939, when a tropical storm struck the Long Beach and San Pedro area. Los Angeles received 5.62 inches of rain over three days, and the storm produced gusts reaching approximately 65 mph.
Researchers have also concluded that a hurricane may have directly affected Southern California in 1858, when a powerful storm passed near San Diego and produced tropical-storm-force winds as far north as the Long Beach area.
That history illustrates just how unusual it would be for an intact hurricane to arrive in Los Angeles.
What to Watch Before Labor Day
For now, there is no indication that Los Angeles residents should prepare for a direct hurricane strike. There are also no tropical storm or hurricane watches or warnings in effect for Southern California as of Tuesday morning.
Marie is, however, expected to strengthen into a hurricane, and its eventual turn later this week will determine whether Southern California receives rain or simply large surf — or potentially very little at all.
The National Weather Service summed up the situation by noting that Labor Day weekend remains a period worth monitoring because of the unusually broad range of possible outcomes.
For Los Angeles, the headline right now isn’t that a hurricane is coming. It’s that a hurricane developing off Mexico could influence Southern California’s Labor Day weekend, with high surf and dangerous rip currents currently the more certain threats and tropical rainfall remaining a possibility.
Sources: National Hurricane Center — Tropical Storm Marie · National Weather Service Los Angeles/Oxnard Forecast Discussion · Los Angeles Times — Southern California Labor Day Tropical Weather
