Many people are caught off-guard by the San Francisco weather. We have a unique climate here - one that is much cooler than the rest of California.
The city is surrounded on three sides by cool water. When warm air mixes with this cool water, it creates fog.
This is what we like to refer to as our 'natural air-conditioning'.
Although you will find fog all along the western coast of the US, SF is the most affected due to the water that surrounds the city. This keeps the city a comfortable, even temperature throughout the year.
In the picture below, you can see the clear day - with the fog starting to roll in under the Golden Gate Bridge. The hazy look of the bridge is also due to the fog.
Although many people associate San Francisco weather with fog, it isn't foggy here all of the time. Most days, it's sunny and beautiful - with a little fog rolling in at night. You will also find that it is foggier (both during the day and at night) during certain times of the year.
We also get quite a bit of wind. The wind blows in from the Pacific Ocean.
Since there is a large opening (where the Golden Gate Bridge now sits) between the ocean and the SF Bay, there is nothing to stop or slow down the wind from reaching the city. It also isn't windy every day, but one more San Francisco weather factor that keeps the city cool most of the year.
Here is a monthly breakdown of the San Francisco weather. As you can see from the table below, the temperature doesn't change much throughout the year - which makes it one of the most desirable places to live!
I often get asked, "What should you wear in the cool weather in San Francisco CA?"
Here you will find a few tips to help you pack the right clothes for your San Francisco vacation.
Most people associate California with warm sunny days and cool evenings. This is true for much of the state - except the city of San Francisco. We have moderate temperatures that are fairly consistent all year around.
To simplify it, it's around 60°, a little breezy and partly cloudy every day of the year. We do have a few ups and downs throughout the year, but your best bet is to plan for this type of weather in San Francisco CA.
You will also find temperature variances from neighborhood to neighborhood. Even if it's warm and sunny in Union Square, it might be foggy and windy in Golden Gate Park.
So, what should you pack to wear while you are here?
By layering your clothing, you can add and remove pieces as necessary. I always bring along a light sweater or jacket - so I can warm up or cool down if needed.
SF is a very casual place. You can wear jeans or casual clothes to almost any event, restaurant or bar.
FYI, Levi Strauss invented jeans here, so we don't often break from that tradition!
This section provides a more detailed look - by season and month - to help you pack for your trip.
Click any of the links below to skip ahead to a specific time of year.
Are you looking for some fun things to do during your visit to SF? Click the links below for a calendar of events for each month.
This is my favorite time of the year in San Francisco. The weather is sunny and beautiful.
The average daily highs are around 70 with the lows at night in the mid-50s. It is rarely foggy during this time, as the temperatures in the surrounding areas are about the same.
During this time, I typically wear a short sleeved shirt and carry along a light sweater. At night, I will add a light jacket - and sometimes move to close toed shoes to stay warmer.
This is the best time of year to wear a skirt and sometimes you can even wear shorts. Although, make sure you have plenty of long pants or jeans too.
We usually just have two months of 'spring weather'. April and May are also nice and sunny.
You will find temps in the mid-60s during the day and mid-50s at night.
A short sleeved shirt along with a light sweater or jacket is your best bet during the day. You should also bring along a warmer sweater or jacket at night. Layering is key, so you can add and remove items throughout the day.
Click the two links below for more information on what the weather is like these two months in SF.
These three months are the hardest to understand since the weather forecast and average temperatures can be deceiving.
By looking at the temperatures, you will see the average highs in the upper 60s. At night, the temperatures only drop down to the mid-50s. Perfect - right? Yes and no.
While the weather is still beautiful this time of year, it can change quite a bit from one day to the next due to the fog. One day it might be 75, sunny and gorgeous - and then the next day, you might wake up to fog, wind and temps around 55.
The other thing that happens during these months is that the temperature fluctuates throughout the day. Even though you wake up to fog - it might burn off during the day and warm up quite a bit.
You also might wake up to a sunny, warm morning and then get chilly in the late afternoon when the fog and wind start to roll in for the night.
During these months, it's important to pack several items that you can layer. Here are a few things you should bring along during these months:
Make sure you can mix and match everything above. This allows you to move your clothes around if it's warmer or cooler than expected on any given day.
If you are often cold like me, then you can leave the shorts at home.
This is a picture I took during a foggy summer day. It looks like it's going to rain - but it's just a heavy layer of fog over the Golden Gate Bridge.
This is another picture I took around the same time of year. As you can see, even if its foggy one day - the next might be clear and sunny!
November to March is our rainy season. The temperatures are slightly cooler both during the day and at night.
During the day, the temperatures hover around 60. At night, they drop down to around 50 - and some nights even cooler.
You will want to bring along medium weight shirts, sweaters and at least one jacket. Again, this allows you to layer - as the temps can be different from day to day.
You will also want to prepare for the rain. We get a light rain that is easy to walk in but might last all day. We rarely have thunderstorms and it's not very common for us to get downpours.
Your best option is to bring along a medium weight raincoat that you can wear all the time. I also don't mind the rain, so usually don't carry an umbrella.
Yes - I get a little wet, but it's better than having to deal with an umbrella all day! However, bring one along if you want to stay completely dry.
Click the links below for additional details by month.
Here are some examples of the lighter sweaters and jackets that work almost any time of year for the weather in San Francisco CA:
Looking at the weather for San Francisco CA online is a little deceiving. You need to make sure you select a location that is directly in San Francisco for the most accurate forecast.
If you are looking at the weather at SFO (which is the default location for most weather sites), it's going to show up warmer or cooler than the city itself. SFO is warmer in the summer and slightly cooler in the winter.
To get the most accurate San Francisco weather forecast, type in a specific zip code such as 94133 (Fisherman's Wharf) or 94102 (Union Square). This will pinpoint the temperature in the area of the city you are visiting.
If you are watching the weather forecast on TV, you will notice that there are three different temperature ranges.
This is for the other half of SF. It's also for the locations just north and east of San Francisco that are on the water. These temperatures are usually about 10 to 15 degrees warmer.
This is the temperature for those visiting Fisherman's Wharf, Alcatraz and other sites on the east side of San Francisco. It's also the temperature for those visiting Berkeley, Oakland, Sausalito or Tiburon.
The inland area temperatures are for areas that are not along the water. These are usually about 35 to 40 degrees warmer in the summer. In the winter, they can be up to 20 to 25 degrees cooler.
These are for those visiting San Jose, Santa Rosa and areas to the east such as Walnut Creek. There is a wide variation in temperatures based on location.
What is the San Francisco weather vs. Oakland? San Francisco stays a cool 60 or so degrees all year long. It's a little warmer in Oakland in the summer and about the same in the winter. In Oakland, you will find higher temps in the summer months (70 to 75) and about the same temps in the winter months (58 to 61). At night, it's about the same with temperatures only about 1 to 2 degrees different than the San Francisco weather.
What is the San Francisco weather vs. San Jose? The weather in San Jose is warmer than in SF. Temps are fairly consistent between these two cities from November to February. The rest of the year, the San Jose weather is warmer. You will find temps up into the 80s from June through September, but still cooling down into the upper 50s at night.