San Francisco Bay Area Overview

This is where I've lived for the past 22 years. In a state known for its diversity, the Bay Area is one of the most diverse and interesting areas in the state. Part of the reason is its geography. The Bay Area is a lot like a target, with the Bay as its bullseye, the cities as the next ring out, the mountain ranges outside of that, and the Pacific Ocean, the Sacramento River Delta, and the Central and Salinas Valleys on the outermost ring.

Golden Gate Bridge at sunset from Lawrence Hall of Science
Bay and Golden Gate Bridge from the Berkeley Hills

This diverse geography results in wide variations of micro-climates. On a typical summer day, it may be 55 degrees and foggy on San Francisco's Ocean Beach, 65 and sunny at the Bay Bridge, 70 in Redwood City, 80 in San Jose, and 90 in Livermore (and Sacramento and Fresno may be in the 100's). When a winter rainstorm comes in from Alaska, parts of Marin County may be inundated with several inches of rain, while southern Santa Clara County may be left dry. A storm from Hawaii may do the opposite.

The vegetation varies with the micro-climates. The Santa Cruz Mountains on the west side of the Bay are covered with fog-loving redwood trees, many over 200 feet tall. The Diablo range on the east side is much dryer and is covered with oak trees, brushy chapparal, and grasses. Along the Bay are wetlands covered with pickleweed and other low vegetation. The Oakland-Berkeley Hills are a mixture of eucalyptus and second-growth redwoods.

San Francisco Bay National Wildlife Refuge Newark
San Francisco Bay National Wildlife Refuge, near Fremont

The cool, foggy ocean breezes keep the forested Santa Cruz mountains green all year round. The long, dry summer weather dries up the east bay mountains, turning them a desert tan. In the winter, however, the rains cause them to burst into life in a lush green carpet. Occasionally, winter snow flurries will dust the tops of the highest peaks, sending hordes of snow-starved families up the mountain roads to play in the snow before it melts.

Snow-topped Mt. Hamilton and green hills
Mt. Hamilton east of San Jose in the winter, dusted with snow

For the most part, the Bay Area cities are connected to each other in a big chain around the Bay, but each has its own unique character. The South Bay cities of Silicon Valley are the brains of the Bay Area, with their technology and research-oriented industries. The East Bay and upper Peninsula cities are the muscles, with their shipping and heavy industries. Berkeley and Santa Cruz are dominated by their University of California campuses, and have a more liberal, experimental mindset. Marin County is hot tubs on redwood decks overlooking yacht harbors. It's also the headquarters of George Lucas' Star Wars empire. Napa and Sonoma are the gateways to the Wine Country. The Diablo Valley is a rapidly-growing area, catching the growth spillover from the rest of the Bay Area. Finally, San Francisco is truly unique, not only in the Bay Area, but in all the world.

Oakland and Bay from Lawrence Hall of Science
Oakland and Bay from the Berkeley Hills

San Francisco is the cultural, political, and financial heart and soul of the Bay Area. Until San Jose passed it recently, it was the largest city in the Bay Area. It is geographically one of the most diverse cities in the country, with mountains, steep hills, valleys, lakes, ocean beaches, and bayfront land, all concentrated in a small package. It has the most diverse population, with people from all over the world. Its Chinatown is one of the largest in the world outside of Asia. It has a large Italian, Irish, and Hispanic population. Of course, it's also famous as one of the most tolerant cities of cultural differences. It has one of the largest gay populations in the country. It became a hippie mecca in the 60's, and some of that "Flower Power" attitude still exists. Its natural location and manmade structures make it one of the most scenic cities in the world. Its variety makes it one of the top tourist destinations in the world.

San Francisco from Fisherman's Wharf at twilight
San Francisco skyline from Fisherman's Wharf

When to Visit

If you're wondering when is the best time to visit the Bay Area, the answer depends on where you're going and what you want to do. Summertime is best for outdoor activities in the upper Santa Cruz Mountains, the East Bay, the Peninsula, the northern South Bay, and Marin County. The days are long, and the weather is sunny, but not too hot. If you want to go inland, however, such as to the Livermore Valley or the Central Valley, summers can be very hot. Many attractions, such as Great America and water theme parks, are only open during the summer.

One thing you won't see in the summer in the Bay Area, or anywhere south of it in California, except in the high Sierras, is rain. These parts of California receive less rain in the summer than Arizona. That's good if you don't like getting wet. The air is dry, so the summer temperatures are more tolerable. There's little standing water, so mosquitoes are not a big problem in most areas. On the downside, creeks dry up, reservoirs are drawn down, and the hills turn brown, so it's not the best time for sightseeing in many areas.

San Francisco and many areas along the coast, however, may be too cold in the summer. What happens in the summer is that the sun heats up the air in the valleys, which causes the air to rise. As it rises, it sucks in the cold air off of the ocean inland, which turns into fog. As Mark Twain said, "The coldest winter I ever spent was a summer in San Francisco." The fog only drops the temperatures into the mid-50's, but it can feel colder. Many tourists who come to San Francisco in T-shirts and Bermuda shorts in the summer are often unpleasantly surprised, much to the benefit of the local sweater merchants. Summer is a good time to see the indoor attractions, like the museums and shops, but if you go on the weekends, you may face big crowds and scarce parking.

The warmest days in San Francisco and the coast are during September and October. It's probably the best time to come. The peak of the tourist season is over, the kids are back in school, the weather is clear, and the days are still relatively long. Fall is a good time to visit anywhere in the Bay Area. It's one time when the weather is almost the same everywhere. Unlike other parts of the country, it isn't announced by sudden changes in the colors of the leaves. Without very cold nights, many trees keep their leaves until late winter, but their leaves just turn a dry brown and drop, never wearing bright fall colors. Many others stay green all year round. A few trees, particularly the sweet gum and Chinese pistache, will turn bright red and orange, but they gradually change color and stay that way for months. That amazes people from other parts of the country, who are used to brief flashes of intense color, then a sudden loss of leaves everywhere.

Winter is a good time to come, but its like rolling dice. Winter is the rainy season. That doesn't mean it rains all the time. It may be wet and drizzly for days at a time. It may be sunny and clear for weeks. You never can tell. This winter, it rained so much in December, there were floods everywhere. From January on, however, there was hardly any rain. One winter a few years ago, it didn't rain much at all until March, when we got enough rain to fill the reservoirs. Thanks to weather satellites, they can usually predict when it won't rain, but it's harder to predict when it will rain. They can see the storm clouds forming thousands of miles away in the Pacific, but the clouds are often diverted north as soon as they hit land by high pressure ridges. Unlike Midwestern storms, which tend to be quick, intense, and violent, with thunder and lightning, Bay Area storms tend to creep up slowly, build gradually in intensity, and fade away. Thunder and lightning occur infrequently, and usually in the mountains. Lightning rods and lightning arrestors are seldom used. Long, sustained winter rains can often result in floods and landslides. Certain roads, which are popular with tourists, are often closed by mudslides. Highway 1 is almost always getting washed out, particularly around Big Sur, Devil's Slide (south of San Francisco), and in Southern Marin County. Highway 17 and Highway 9 from the Santa Clara Valley to Santa Cruz are also frequently closed. Avoid these roads in rainy weather. Landslides can happen without warning, and they don't wait for your car to go safely by before they occur. This year, they're already worrying about the effects of El Nino this winter. In case you haven't heard, the El Nino effect is a warming of the waters around the east central Pacific Ocean, which can result in heavy rains in California.

Despite all this, I love winter. The skies after a rain are crystal-clear. The air is crisp and invigorating. The clouds put on more of a show, which is great for photography (summer can be downright boring, cloudwise). It gets cold at night, but the days usually are in the 50's or above. The dead hills come alive with greenery. Dry rivers start flowing again. Winter in California looks a lot like spring in other parts of the country. This is the best time to go whale-watching along the coast. The elephant seals come to mate at certain beaches. The monarch butterflies coat the trees in parts of Pacific Grove and Santa Cruz. Many of the tourist attractions, the ones that are open this time of year, are the least crowded, but days are short. The beaches are gorgeous and almost deserted, unlike summer, when they can be jammed with heat-fleeing valley residents.

While the areas close to the coast and bay may be clear in the winter, areas farther inland, particularly in the Central Valley, can be socked in by a dense fog called "tule fog." Visibility can drop to almost zero, and driving can be extremely hazardous. During the winter, huges masses of people from the Bay Area stream into the Sierras to go skiing. Unfortunately, they have to cross through the Central Valley en route, and often get into accidents due to the fog.

Spring is great everywhere in the Bay Area, but like fall, it doesn't really announce itself. It's more of a drying out phase between winter and summer. The rains let up, the hills start losing their rich green color, and the creeks slow down. It's the best time for sightseeing and hiking, however. The winter rails often make trails impassible, but by spring, they may be dry enough to hike on. Wildflowers start splashing the green hills with bright colors. By spring, the washed-out roads have hopefully been cleared. The weather is clear and mild in all regions. Even the Central Valley is nice. The tourist attractions are not too crowded, as long as you avoid the school vacation times, which can vary.

The bottom line is that there really isn't a bad time to visit the Bay Area. You just have to be aware of the conditions you may face and be prepared. Check the news sources and the Internet for the latest weather and road conditions.


Greater Bay Area

San Francisco

Santa Clara County

    This is my home, Santa Clara County, South Bay, San Jose. Santa Clara County consists of most of "Silicon Valley" and parts of the surrounding Santa Cruz and Diablo Mountains. It extends down through the rural Coyote Valley and includes the developing farm towns of Morgan Hill and Gilroy. The largest city is San Jose, the county seat. San Jose is the largest city in the Bay Area. It's the third largest city in California, the eleventh largest in the U.S., and the largest city on the west coast of North America north of Los Angeles. The once run-down downtown area has been going through a Renaissance in the past couple decades and has become a major attraction, with its many fine restaurants, luxury hotels, theaters, convention center, and museums. The county's namesake, the city of Santa Clara, is at the heart of Silicon Valley and includes some of its biggest and most well-known companies, like Intel and National Semiconductor. It also has historical Mission Santa Clara inside the University of Santa Clara. Cupertino is the home of Apple Computer. Sunnyvale and Mountain include many high-tech companies and defense firms. They also have parks and open spaces along San Francisco Bay. Palo Alto is the home of Stanford University. It is often considered the birthplace of Silicon Valley, as famous high-tech firms such as Varian Associates and Hewlett-Packard started here. Los Altos, Monte Vista, Saratoga, and Los Gatos are wealthy communities that reach into the redwood-forested Santa Cruz mountains.
    The Santa Clara Valley was originally called "The Valley of the Heart's Delight." Its broad, fertile fields were once covered with orchards of prunes, apricots, and cherries. The blossoming of the trees were a beautiful sight in the springtime. In the 1950's, it was the tenth largest growing area in the U.S. Nowadays, these orchards are almost all gone. One of the largest remaining orchards is ironically on IBM's property at its south San Jose disk drive plant. The rest have been turned into the industries, stores, and houses covering what is now the "Silicon Valley."
    "Silicon Valley" is an unofficial nickname for the Santa Clara Valley and parts of adjoining counties, depending on who you talk to. It's name comes from the silicon used in making integrated circuits. In general, it refers to the high-concentration of high-technology companies in the area, not just semiconductor companies. The valley has seen boom and bust times and will probably see many more. Currently, it's recovering from a downturn in the semiconductor and defense industrics and riding a wave of success in the Internet, communications, and software industries. Disk drive manufacturing is also big here. It is currently one of the richest areas in the country, with low unemployment in high-paying, highly-skilled jobs. Unfortunately, this has also caused the valley, as well as the Bay Area in general, to be one of the most expensive and tightest housing markets in the nation.
    Because of its many high-tech companies, the valley is heavily visited by business travelers. The numerous multi-story, business-class hotels in downtown San Jose and near the San Jose International Airport are often filled with businesspersons during the week. Still, the valley is not all business. There's plenty for tourists and families to see and do. See the links below for more information. Go to my home page for information on specific topics on things to do.

Alameda County

Contra Costa County

Solano County

Marin County

Wine Country

Santa Cruz County

Monterey County

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Ron Horii, San Jose
Created 10/8/97. Last update: 2/20/99