San Francisco’s climate is dry-summer temperate with average temperature of 14.05 °C and annual rainfall 600 mm, while Las Vegas has a desert climate, with an average temperature of 20.75 °C and annual rainfall 106 mm, and Los Angeles’ climate is warm and temperate with average temperature of 17.65 °C and annual rainfall 474 mm.
The seasons in San Francisco, Las Vegas and Los Angeles are as follow:
- Spring – March to May are months when the temperatures are mild and there are fewer crowds, which is perfect for walking around. As Las Vegas’ temperatures drop significantly at night, it is recommended to prepare a few light layers.
- Summer – June to August is peak tourist season for San Francisco and Los Angeles with many fun festivals for visitors to participate in. It is warm in San Francisco and Los Angeles, with San Francisco experiencing chilly, damp fog and Los Angeles heavy smog. Las Vegas gets really hot in summer, with July and August seeing more rainfall though showers are often short-lived.
- Autumn – September to November are months when crowds get lesser, and Las Vegas and Los Angeles enjoy a reprieve from the summer heat. San Francisco is warmer in autumn than in summer, though it is recommended to pack a few layers as bayside breezes can get chilly.
- Winter – December to February are months when the cities get the most rainfall and experience cool weather. San Francisco may feel really chilly because of its fog and cold winds. Las Vegas sees a high influx of visitors due to its many holiday parties.