Hurricanes and California: Why They're So Rare — and What Happens When One Shows Up

In August 2023, millions of Californians found themselves doing something the state had almost never asked of them before: preparing for a tropical storm. Hurricane Hilary, after slamming into Mexico's Baja California Peninsula, marched north toward Southern California and prompted the region's first-ever tropical storm watch. Streets in Palm Springs turned into rivers, mudslides closed mountain roads, and Death Valley recorded roughly two inches of rain in a single day — more water than the park typically sees in an entire year, and the wettest day in its recorded history.
For a state famous for sunshine and earthquakes, the sight of a tropical system bearing down on the coastline raised a lot of questions. Does California even get hurricanes? Why are they so rare? And if one is heading your way, what should you actually worry about?
Does California Get Hurricanes?
The short answer: almost never as full-strength hurricanes, but their remnants and weakened leftovers show up more often than most people realize.
A hurricane is a tropical cyclone with sustained winds of at least 74 mph. When a storm weakens and its winds drop below that threshold, it's reclassified as a tropical storm, and below that, a tropical depression. Even when a system loses its hurricane status, it can still carry enormous amounts of moisture — and that moisture is what actually poses the biggest threat to California.
In the entire recorded history of the state, only one tropical storm is confirmed to have made landfall in California: the Long Beach Tropical Storm of September 1939. It came ashore with heavy rain and wind, caught residents largely off guard, and killed dozens of people, many of them aboard boats caught at sea. The storm was so unusual that it became a benchmark event meteorologists still reference today.
Hurricane Kathleen in 1976 came close to repeating history. After crossing Baja California, it pushed into the state and unleashed destructive flooding on desert communities in the Imperial Valley, drowning farmland and washing out roads. Hurricane Nora in 1997 brought significant rain and flooding to parts of Southern California as well. And in 2023, Hilary crossed into the state as a tropical storm, delivering the kind of rainfall Southern California had simply never experienced from a system like it.
Why the California Coast Is So Unfriendly to Hurricanes
Three main factors keep hurricanes away from the Golden State, and the most important one is water temperature.
Hurricanes are heat engines. They need warm ocean water — generally around 79 to 80 degrees Fahrenheit or warmer — to form and maintain their strength. The Atlantic and Gulf coasts get plenty of water that warm in summer. The Pacific coast off California does not. The California Current, a cold, southward-flowing ocean current, keeps coastal water temperatures in the 50s and 60s for most of the year. When a hurricane's circulation taps into water that cold, it loses its fuel source and weakens rapidly.
The second factor is steering. Most hurricanes in the eastern Pacific form off the coast of Mexico and are pushed westward and northwestward by prevailing winds — out over the open ocean, away from land. The storms that do curve north toward Baja California usually run into the rugged terrain of the peninsula, which disrupts their circulation before they can reach the U.S. border at full strength.
Third, even when a storm survives the journey north, the same cold water that starves it also strips away its tropical characteristics. By the time a system reaches California waters, it's usually a shadow of what it was — a weakening tropical storm or a sprawling remnant loaded with rain rather than wind.
That said, "weakened" doesn't mean "harmless." Hilary proved that clearly.
The Real Danger: Water, Not Wind
When people think of hurricanes, they tend to picture wind tearing roofs off houses. In California, the danger profile is different. Water is the threat that matters most.
Desert flooding. Communities like Palm Springs, Cathedral City, and the broader Coachella Valley sit on low-lying desert terrain. When a tropical system drops several inches of rain in a few hours, the water has nowhere to soak in. Streets flood fast, and dry washes can become torrents.
Flash floods in canyons and burn scars. Areas burned by recent wildfires are especially vulnerable. Without vegetation to hold soil in place, even moderate rain can send fast-moving mud, rock, and debris downhill. Debris flows are among the deadliest hazards a California storm can produce.
Mountain rain and swollen creeks. Tropical moisture streaming into the Sierra Nevada and Southern California mountains can dump extraordinary rainfall totals at elevation, swelling creeks and rivers that normally run quiet.
Dangerous surf and rip currents. Even a storm that stays hundreds of miles offshore can generate large swells that reach California beaches, putting swimmers and surfers at risk days before any rain arrives.
Wind damage, while possible, usually plays a supporting role by the time storms reach the state. Emergency managers in California worry far more about people driving into floodwater than about windows blowing out. The rule safety officials repeat every storm season is worth memorizing: never drive through a flooded roadway. Just six inches of moving water can knock an adult off their feet, and a foot of water can float many vehicles. It takes far less depth than most drivers assume.
Is Climate Change Increasing the Risk?
This is a question scientists are actively studying, and honest answers come with caveats.
What's well established: warmer air holds more moisture, so when tropical systems do reach California or send their remnants north, they have the potential to carry heavier rain than similar storms in the past. Ocean surface temperatures have also been running warmer in recent years, including along portions of the Pacific coast, which reduces one of the natural barriers that has long protected the state.
Whether that translates into more frequent tropical storm landfalls in California is far less certain. Storm tracks depend on large-scale wind patterns that vary year to year, and no one can say with confidence that Hilary-style events will become routine. What researchers do generally agree on is that the odds of tropical moisture influencing California weather — and dropping extreme rainfall when it does — deserve serious attention. For residents, the practical takeaway is simpler than the science: the assumption that "storms like that don't happen here" is no longer a safe one.
How to Prepare if a Tropical Storm Heads Toward California
Preparation for a tropical system in California looks a lot like preparation for a severe winter storm, with a few extras.
Know your flood risk. If you live near a creek, in a desert wash area, below a recent burn scar, or on a street with a history of ponding, you're in the zone that matters most. Your city or county flood control district can tell you more about your specific exposure.
Sign up for local alerts. Most California counties run free emergency notification systems that send texts or calls about evacuations, road closures, and shelter locations. The National Weather Service office covering your area is the best source for watches and warnings — remember that a watch means conditions are possible, while a warning means flooding or storm impacts are expected or already happening.
Keep basic supplies on hand. Water, shelf-stable food, flashlights, batteries, medications, and phone chargers will carry you through a 24-to-48-hour disruption. Add sandbags if you're in a flood-prone spot — many fire stations and public works departments distribute them free before major storms.
Plan around the water. Identify which routes out of your neighborhood stay on higher ground. If officials close a flooded road, take the detour seriously rather than treating it as a suggestion.
During the storm, stay out of the obvious trouble spots: flowing washes, flooded underpasses, coastal waters with big surf, and canyon roads in burn-scar areas. Most tropical storm deaths in the United States come from drowning, not wind.
Common Questions People Ask
Could a full-strength hurricane ever hit Los Angeles or San Diego directly? It's not physically impossible, but it would require a rare combination: unusually warm coastal water, a storm tracking perfectly north along Baja California, and conditions that preserve its structure the whole way. In practice, any system reaching California would almost certainly arrive weakened — but as Hilary showed, a weakened tropical storm is still capable of historic rainfall.
When is hurricane season in the eastern Pacific? It runs from May 15 through November 30, with activity typically peaking in late summer and early fall. That overlaps with California's own late-summer thunderstorm season, which is why August and September tend to be the months when tropical moisture finds its way north.
What was the biggest hurricane-related event in California history? By landfall standards, the 1939 Long Beach tropical storm remains the defining event. By rainfall and disruption, Hilary in 2023 set a modern benchmark, becoming the first tropical storm watch in Southern California history and producing record flooding across the desert regions.
A Storm Worth Taking Seriously
California's coastline is one of the most hurricane-protected places in the country, and that's unlikely to change fundamentally. But the state's relationship with tropical systems isn't defined by wind — it's defined by water. When warm, moist air from a decaying Pacific hurricane meets California's mountains, deserts, and burn scars, the result can be flooding on a scale the state rarely sees from any other weather event.
Hilary didn't need hurricane-force winds to close national parks, swamp highways, and strand residents. The next storm won't either. Treating tropical storm watches in California with the same seriousness that Gulf Coast residents treat hurricane warnings is, increasingly, just common sense.