- By Kevin
- On Jul 14, 2017
- North America
- Travel Tips
San Francisco is located in California, on the west coast of the United States of America, and is a popular tourist destination, enjoying mild, dry summers and cool, wet winters. With several micro-climates due to its geography, the weather averages can vary greatly across the city and throughout the months. The hottest month of the year on average is July and the coldest is January, which is also the wettest month. The unpredictable climate means the weather is hard to predict and hot days can occur during the autumn months. The city has many tourist attractions such as the Golden Gate Bridge, Alcatraz, and its alternative, liberal counter-culture that has been a part of city life since the 1960’s. The area is susceptible to earthquakes and has had many severe earthquakes in the past. The last major earthquake was in 1989 and measured 6.9 on the Richter scale.
The topography of San Francisco and maritime location at the end of a peninsular, surrounded by the Pacific Ocean and San Francisco Bay, create little year-round temperature variation. The city is also well-known for its foggy conditions, mainly occurring during the summer months, as the hot air rising in California’s inland valleys creates low pressure, pulling in winds from the North Pacific and creating the fog.
The weather is variable across the San Francisco Bay area but is generally warmer on the bay side then on the ocean side. It is also foggier on the west side as the fog rolls in from the Pacific Ocean. It is important to pack for all weather conditions when visiting San Francisco, and layering is essential. The weather can change in an instant as cold winds can blow in from the Pacific Ocean without warning making a warm, sunny day suddenly feel like winter. The fog can be the summer’s natural air conditioner as it cools the day considerably as it blankets the city.
The highest recorded temperature was 390C in July 1998 and in 2000, while the lowest recorded temperature was -30C in December 1932. Precipitation varies greatly from year to year depending on the conditions in the Pacific Ocean. El Nio years bring warmer air and above average rainfall, while colder, drier La Nia conditions bring less rain to the city. The summer fog follows a pattern of sunny mornings heating up the land, with low pressure occurring by the middle of the day. As the maritime wind increases, it pushes the fog inland and is unable to evaporate, causing the famous foggy conditions that San Francisco is known for. Take a look at the weather forecast and find out how the averages are calculated here.