Marin Microclimates
Fog belt or sun belt? A native’s town-by-town guide to Marin weather, and what it means for the house you buy
Last updated September 2026 · By Melissa DiVita, REALTOR®, Compass · DRE #01387955 · Marin native, in real estate since 2003
Here’s something no listing will tell you: two houses fifteen minutes apart in Marin can feel like different states. On a July afternoon it can be foggy and in the 60s on the Sausalito waterfront and in the 80s in Kentfield. It’s easy to fall in love with a house at a sunny October open house and discover the next summer that it sits in the fog.
Weather shouldn’t be an afterthought when you choose a town. It affects your garden, your heating bill, whether you use that deck, and even how the house holds up. This is how I explain Marin’s microclimates to buyers, with the numbers behind it. (For the personal version, read how fog, wind and afternoon sun shaped my own family’s moves.)
Why Marin has so many climates
- The Golden Gate is a fog funnel. In summer the marine layer pours through the gap and into southern Marin and the coast. The layer is usually 1,000 to 2,000 feet thick, which is why Mt. Tam’s summit, at about 2,500 feet, often sits in sunshine above it.
- Mt. Tam blocks and shelters. The towns tucked behind the mountain and the ridges, like the Ross Valley, San Rafael and Novato, are sunnier and warmer in summer.
- The mountain also pulls down the rain. Storms rise over Mt. Tam and drop their rain on its slopes, so Kentfield is one of the wettest places in the Bay Area, while the Point Reyes headlands get far less.
- Slope and canyon matter house by house. Steep, north-facing, heavily wooded canyons stay noticeably cooler and damper than the sunny side of the same hill.
The numbers
| Place | Average July high | Average January low | Rain per year |
|---|---|---|---|
| Kentfield | 82.5°F | 41.9°F | 44.4 inches |
| San Rafael (Civic Center) | 80.9°F | 42.6°F | 34.5 inches |
| Point Reyes headlands vs. Bear Valley | Inland Bear Valley runs about 20°F warmer than the headlands in summer | — | About 11.5 inches at the lighthouse vs. about 36 inches at Bear Valley |
Kentfield and San Rafael are NOAA 1991–2020 normals. Point Reyes figures are from the National Park Service. There’s no official station in most southern Marin towns, so I describe them below rather than quote numbers.
Town by town
| Area | Summer weather | What I tell buyers |
|---|---|---|
| Sausalito | The Marin Headlands shelter the town, and the fog often stops at the ridgeline, so the upper hillside neighborhoods can be sunny while the Golden Gate is socked in. Old Town is nicknamed “Hurricane Gulch” for the afternoon wind that blows down its narrow valley. | Visit on a summer afternoon, not just a sunny fall weekend. Which side of the hill you’re on makes a big difference. |
| Southern Mill Valley, Tam Valley, Homestead Valley, Muir Beach | The closest to the fog. Muir Woods is regularly wrapped in summer fog, and the redwood canyons stay cool and damp. | Beautiful and green, but check for moisture, mildew and drainage in canyon homes, and expect to use the heat in summer evenings. |
| Mill Valley (sunnier pockets) | Mill Valley is a patchwork. The steep, north-facing, forested canyons are noticeably cooler and moister than the rest of town, while south-facing hillsides get far more sun. | Look at which way the house and yard face. It’s one of the first things I check. |
| Tiburon and Belvedere | Out on the peninsula, with Bay breezes and views over Richardson Bay. Summer afternoons can be windy on the water, which is exactly why wing foilers love Paradise Cay. | Ask about wind on the deck and on the water side of the house. |
| Corte Madera and Larkspur | In between the fog of southern Marin and the summer heat of the Ross Valley. | A good compromise if you want sun without the Ross Valley heat. |
| Kentfield, Greenbrae and Ross | Sunny and warm in summer, and in winter one of the wettest places in the Bay Area. | Great for gardens and pools. Ask about drainage, gutters and the creek, and look at the house after a real storm if you can. |
| San Anselmo and Fairfax | Warm, sunny summers in the Ross Valley. | Pools and outdoor living get used here. Check how close the house is to the creek. |
| San Rafael (Gerstle Park, Terra Linda, Lucas Valley) | Warm and sunny. Terra Linda and Lucas Valley sit farther from the Bay. | A lot of sunshine for the money. Ask about summer cooling in homes without air conditioning. |
| Novato | The warm, sunny north end of the county. | Plan for hotter summer days, and look at shade and cooling. |
| Stinson, Bolinas, Point Reyes and Inverness | The coast. Point Reyes is known as one of the foggiest and windiest spots on the West Coast, with fog peaking from July to September. | The magic is in the drama and the quiet. Inland spots like Inverness Park and Olema are warmer than the shore. |
How to check a house’s weather before you buy
- Visit at 4 p.m. in July or August. That’s when the fog and wind show up. A sunny fall open house doesn’t tell you much.
- Check which way it faces. South- and west-facing yards get the sun; north-facing canyon lots stay shady and damp.
- Ask about heating and cooling. Many Marin homes don’t have air conditioning. In the fog belt that’s fine, but in Novato or the Ross Valley you may want it.
- Look for moisture. In canyon and fog-belt homes, look for mildew, rot and drainage issues, and make sure your inspector does too.
- Think about how you’ll use the outdoor space. A pool makes more sense in Ross than in Muir Beach. A view deck in Sausalito may want a wind screen.
What this means for where you buy
If you want warm summer afternoons, a pool and a garden that thrives, look at the Ross Valley, Kentfield, San Rafael and Novato. If you love cool, green, foggy mornings and redwoods, southern Mill Valley and the canyons are magic. If you want a bit of both, Corte Madera, Larkspur, Tiburon and the sunny side of Sausalito are the compromise. Growing up here, I learned the weather town by town, and I’m happy to share what I know about a specific street.
See my town guides and my homeowners insurance guide, which covers fire and flood.
Frequently asked questions
What is the sunniest town in Marin?
In summer, the towns sheltered from the Golden Gate fog are the sunniest and warmest: the Ross Valley (Ross, San Anselmo, Fairfax), Kentfield, San Rafael and Novato. Kentfield averages a July high of about 82.5°F and San Rafael about 80.9°F, based on NOAA 1991–2020 normals.
Which parts of Marin get the most fog?
The areas closest to the Golden Gate and the coast get the most summer fog: the Sausalito waterfront, southern Mill Valley, Tam Valley, Homestead Valley, Muir Beach, Stinson and Point Reyes. Point Reyes is known as one of the foggiest and windiest places on the West Coast.
Where does it rain the most in Marin?
Kentfield, at the foot of Mt. Tam, is one of the wettest places in the Bay Area, averaging about 44 inches of rain a year based on NOAA 1991–2020 normals. The Point Reyes headlands get far less, about 11.5 inches at the lighthouse.
Why is it called Hurricane Gulch in Sausalito?
Hurricane Gulch is the nickname for Old Town Sausalito, because of the strong afternoon winds that often blow down its narrow valley.
Sources
- Kentfield, California (NOAA 1991–2020 climate data)
- San Rafael, California (NOAA 1991–2020 climate data)
- Bay Nature: which spot in the Bay Area gets the most rain
- National Park Service: Point Reyes climate
- KQED: above the marine layer
- Mill Valley, California
- Muir Woods National Monument
- OurSausalito: fog in Sausalito
- OurSausalito: Old Town (Hurricane Gulch)
Want sun, fog or a bit of both?
Send me a note through my contact form. Tell me how you want to live, and I’ll show you the towns and streets that fit.