You’re driving down the 101 with the sun beating on your dashboard, looking at palm trees and brown hills, and you think: "Man, this place is a total desert." It makes sense. It’s hot. It barely rains. The grass turns into crunchy straw by July. But if you actually ask a geologist or a botanist is Los Angeles in a desert, they’ll probably give you a look that says "well, yes, but mostly no."
It’s complicated.
Honestly, the "LA is a desert" thing is one of those urban myths that everyone just kind of accepts because it looks the part. We see the dust and the heat waves, and we assume we're in the Sahara’s cousin. But Los Angeles is actually a Mediterranean climate, which is surprisingly rare. Only about 3% of the entire planet has it. Think Greece, central Chile, or the tip of South Africa. That’s the club we’re in.
The Rain Math: Why LA Doesn't Meet the Desert Criteria
To be a "real" desert, you usually need to see less than 10 inches of rain a year. That’s the standard baseline most meteorologists use. Los Angeles—specifically the downtown area—averages about 14 to 15 inches of rain annually.
That’s a big gap.
Sure, we’ve had drought years where the sky stays dry for months and we only hit 6 or 7 inches, but on average, we get way too much water to technically qualify as a desert. The rain just all comes at once. We get these massive atmospheric rivers in the winter that dump four inches in a weekend, and then we don't see a drop for six months. It’s feast or famine.
What is a Mediterranean Climate, Anyway?
Essentially, it's defined by mild, wet winters and hot, dry summers. In a desert, it's often dry all the time, or you get random monsoon bursts in the summer. In LA, our summers are bone-dry. If you see a rain cloud in August, it’s basically a local celebrity.
The vegetation tells the story.
If you hike up into the Santa Monica Mountains or the Hollywood Hills, you aren't seeing saguaro cacti. You’re seeing Chaparral. This is a specific biome made of hardy, woody shrubs like Manzanita and Scrub Oak. These plants are built for fire and drought, but they aren’t desert plants. They are coastal sage scrub. They thrive on the morning fog that rolls in from the Pacific—the "June Gloom" that locals complain about but the plants absolutely crave.
The "Desert" Feeling is Often Man-Made
Part of why everyone asks is Los Angeles in a desert is because of how the city looks. We’ve planted thousands of palm trees, which aren't even native to LA (except for one specific species, the California Fan Palm, which mostly hangs out in the actual desert near Palm Springs). We brought in Mexican Fan Palms because they looked cool and grew fast.
Then there’s the concrete.
Los Angeles is a giant heat island. When you cover hundreds of square miles in asphalt, the ground absorbs heat all day and radiates it back at night. This makes the city feel way hotter than the surrounding natural areas. If you stand in the middle of a parking lot in North Hollywood, yeah, it feels like a desert. But if you go to the Topanga State Park, you’ll feel the humidity from the ocean and see the greenery that proves otherwise.
The Real Deserts are Just Next Door
The confusion happens because LA is surrounded by deserts. You’ve got the Mojave to the north and the Colorado Desert to the east. If you drive two hours in almost any direction away from the ocean, you will hit a desert.
The San Bernardino and San Gabriel Mountains act as a massive wall. This is called a Rain Shadow.
Moist air comes off the Pacific, hits the mountains, rises, cools, and drops all its rain on the LA side. By the time the air gets over the peaks to places like Victorville, Lancaster, or Palm Springs, it’s bone-dry. That’s why you can stand in a lush backyard in Pasadena and look at a mountain range, knowing that on the other side, it’s nothing but sand and Joshua trees.
Why Does This Distinction Even Matter?
It’s not just about being a "well, actually" person at a dinner party. Understanding that LA isn't a desert changes how we manage our environment.
- Fire Risk: Because we have a Mediterranean climate, our plants grow a ton in the wet winters. Then they dry out into perfect fuel in the summer. Deserts actually have less fire risk in some ways because there isn't enough vegetation to carry a massive blaze.
- Water Management: Since we aren't a desert, we used to have a lot of local water. But we built a city for millions when the local ecosystem was designed for much fewer.
- Gardening: If you try to plant a "desert" garden in some parts of LA, you might actually overwater it just by living in a humid coastal zone.
The William Mulholland Factor
We can't talk about LA's climate without mentioning the guy who basically stole a river. William Mulholland, the head of the DWP in the early 1900s, knew LA wasn't a desert, but he knew it didn't have enough water to become a metropolis.
He built the Los Angeles Aqueduct to bring water from the Owens Valley. This created a weird paradox: we have a Mediterranean climate, but we’ve imported a "lush" lifestyle with green lawns and swimming pools that doesn't fit the natural rainfall. This makes the city feel like an artificial oasis, further confusing people about what the land actually is.
A Quick Cheat Sheet for LA Geography
If you're still skeptical, look at the "Microclimates." LA is a patchwork quilt of weather.
- Santa Monica/Venice: Definitely not a desert. Often 15 degrees cooler than inland, high humidity, lots of fog.
- The Valley (SFV): Borderline. It gets much hotter and has less ocean influence. It’s the closest "urban" LA gets to feeling like a desert.
- Pasadena: Nestled against the mountains, it actually gets more rain than downtown LA because of the elevation.
Actionable Insights for Navigating LA’s Climate
If you’re living in or visiting LA, don't pack like you're going to the Sahara, but don't treat it like a tropical rainforest either.
👉 See also: Mecca on a Map: Why Your GPS Might Get It Wrong
Layer your clothing. Because we are a coastal Mediterranean zone, the temperature swings are wild. It can be 85 degrees at 2:00 PM and 55 degrees the second the sun goes down. That "desert" dry air means the heat doesn't stick around after dark.
Plant native, not just "desert." If you're landscaping, don't just buy cactus. Look for California Native plants like Ceanothus or California Poppy. They are adapted to our specific cycle of "wet winter, dry summer," whereas some desert cacti can actually rot if they get hit by a weirdly wet LA February.
Respect the sun. The UV index in Southern California is no joke. Even if it feels breezy and cool near the beach, the sun is just as strong as it is in the Mojave.
Los Angeles is a beautiful, weird anomaly. It’s a coastal basin that's just dry enough to keep the sun shining 300 days a year, but just wet enough to keep the hillsides (mostly) green in the spring. It’s not a desert; it’s just its own unique thing.
How to make the most of the LA climate:
- Visit in the "Green Season": Go hiking in February or March. The hills look like Ireland for about six weeks. It's the only time you'll truly see the Mediterranean side of the city.
- Watch the Humidity: If the humidity drops into the single digits, that’s "Santa Ana wind" weather. It’s the only time LA actually becomes a desert for a few days, as hot air blows in from the interior.
- Check the Dew Point: In the summer, the "June Gloom" can keep things damp until noon. If you want sun, head inland; if you want to escape the heat, stay west of the 405.