About When to visit
Forget everything you’ve heard about California being a subtropical paradise where the sun never stops shining and rainfall is unknown. The state is big and varied enough to span several different climatic zones and only southern California comes anywhere near matching the travel brochures’ hyperbole.
Even in the south there are fluctuations. On the coast, San Diego and its surroundings enjoy very warm but largely humidity-free summers and mild winters. By contrast, Los Angeles has sunny days year-round but becomes unpleasantly hot and sticky during the summer, and in winter is prone to torrential rainfall. The city’s notorious smog is at its worst from July to September. During the hot and dry summer months, the deserts of inland southern California veer from uncomfortable to intolerable; desert winters are well within human tolerance, though, and in springtime fabulous displays of blooming wildflowers bring many visitors to these severe regions.
In the north, San Francisco avoids extremes: its summers can be hot but are more often pleasantly warm; the winters are cool but seldom freezing. In common with the north coast, and much of the central coast, San Francisco is prone to fogs, which can bring a chilly, grey start to the sunniest day.
There is more fog, and generally colder and damper conditions, further north along the coast, although the summers here usually bring sunny, rain-free days. Inland, scorching summer temperatures are common in parts of the Gold Country, but winter can bring heavy snowfalls. Similar conditions prevail as you move east, rising through the foothills of the Sierra Nevada mountains. In these parts, the mild summer is the only time to enjoy walking and climbing in the alpine scenery; in winter, skiers take to the snow-covered slopes.
Overall, the best months to be in California are March to May and September and October, but don’t despair if you cannot avoid the peak months of the summer or winter. Provided you pack a strong sunscreen for the southern summer and carry an umbrella in the northern winter, you will find that only the deserts (in summer) and the mountains (in winter, unless you plan to ski) are off-limits.
Clothing If you intend to travel widely around the state, pack with the varying climates in mind. In the hotter, sunnier parts of the state, wear a hat, loose fitting clothes and smother yourself liberally with a powerful sunscreen. Farther north, a warm summer’s day can give way to a surprisingly chilly evening; be sure to have a sweater or jacket handy.
Except in the most elegant restaurants, California dress is always casual, but bare feet and swimsuits are seldom acceptable away from the beach. The national and state parks, and much of the undeveloped coastline, are best seen by walking, so bring suitable footwear.