The best times to visit San Marcos for ideal weather are
March 5th to November 18th
based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.
San Marcos Travel Guide
Other San Marcos Travel Info
Weather in San Marcos
Average temperatures in San Marcos vary somewhat. Considering humidity, temperatures feel very enjoyable all year with a very low chance of rain or snow throughout the year. The area is more temperate than most — in the 85th percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit San Marcos, the hottest months are August, September, and then July. See average monthly temperatures below. The warmest time of year is generally late August to early September where highs are regularly around 79.9°F (26.6°C) with temperatures rarely dropping below 67.2°F (19.6°C) at night.
San Marcos Temperatures (Fahrenheit)
San Marcos Temperatures (Celsius)
The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.
San Marcos Perceived Temperature (F)
San Marcos Perceived Temperature (C)
Average San Marcos Temperatures by Month
Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.
|Month||Avg. High (°F)||Avg. Mean (°F)||Avg. Low (°F)|
|Month||Avg. High (°C)||Avg. Mean (°C)||Avg. Low (°C)|
Precipitation (Rain or Snow)
If dry weather is what you’re after, the months with the lowest chance of significant precipitation in San Marcos are June, September, and then July. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around late May to early June. For example, on the week of May 28th there are no days of precipitation on average. By contrast, it’s most likely to rain or snow in mid December with an average of 2 days of significant precipitation the week of December 17th.
When can you find snow in San Marcos? Weather stations report no annual snow. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.
Chance of Precipitation
The graph below shows the % chance of rainy and snowy days in San Marcos.
Snow on the Ground
The graph below shows the average snow on the ground in San Marcos (in).
Average Rain and Snow by Month
|Month||Daily Chance of Rain||Average Snow Depth (in)||Total Precipitation (in)|
|Month||Daily Chance of Rain||Average Snow Depth (cm)||Total Precipitation (cm)|
Humidity and Wind
San Marcos has some slightly muggy months, with moderately humid months on the other side of the year. The least humid month is January (45.5% relative humidity), and the most humid month is July (69.6%).
Wind in San Marcos is usually extremely calm. The windiest month is May, followed by April and June. May’s average wind speed of around 4.3 knots (5 MPH or 8 KPH) is considered “a light breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in early to mid April where average top sustained speeds reach 10.6 knots, which is considered a gentle breeze.
Relative Humidity (%)
The graph below shows the average % humidity by month in San Marcos.
The graph below shows wind speed (max and average) in knots.
Average Wind Speeds
Show Wind Speeds
All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.
|Month||Avg. Wind||Avg. Wind Feel||Sustained High Wind||High Wind Feel|
|Jan||2.8||Barely noticeable||8||Gentle breeze|
|Feb||3.4||Barely noticeable||9.3||Gentle breeze|
|Mar||3.5||Barely noticeable||9.4||Gentle breeze|
|Apr||4.1||Light breeze||10.1||Gentle breeze|
|May||4.3||Light breeze||9.9||Gentle breeze|
|Jun||3.9||Barely noticeable||9.1||Gentle breeze|
|Jul||3.5||Barely noticeable||8.6||Gentle breeze|
|Aug||3.2||Barely noticeable||8.4||Gentle breeze|
|Sep||3.1||Barely noticeable||8.5||Gentle breeze|
|Oct||2.9||Barely noticeable||8.5||Gentle breeze|
|Nov||2.7||Barely noticeable||8.1||Gentle breeze|
|Dec||3||Barely noticeable||8.4||Gentle breeze|
Show Relative Humidity by Month
|Month||Avg. Relative Humidity|
Is it Safe to Travel to San Marcos?
Our best data indicates this area is generally safe. As of Oct 07, 2019 there are no travel advisories or warnings for the United States; exercise normal security precautions. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Sep 23, 2019.
The Busiest and Least Crowded Months
The busiest month for tourism in San Marcos, CA, US is July, followed by June and May. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit San Marcos in November. Those willing to visit at these times will likely find it the least expensive month.
Estimated Tourism by Month
Most Popular Months to Visit
Overall San Marcos Travel Experience by Season
Spring (March through May)
Humidity and temperatures combine to make this season feel moderate. Highs range from 71.1°F (21.7°C) and 65°F (18.3°C) with warmer temperatures in the later months. Rain is rare with 1 to 2 days of significant precipitation per month. Spring is the second busiest for tourism, which makes it a good time for those looking for things to do.
Summer (June through August)
The middle-year months have very comfortable weather with high temperatures that are comfortable. These months see the least precipitation with about 0 days of precipitation per month. June – August is the busiest season for tourism in San Marcos, so lodging and other accommodations may cost more than usual.
Fall (September through November)
Fall daily highs range from 78.8°F (26°C) and 67.8°F (19.9°C), which will feel very nice given the humidity and wind. It rains or snows a normal amount: 0 to 2 days per month. Tourism is the slowest during these months due to the weather, so hotels may be affordably priced.
Winter (December through February)
Weather is somewhat cool this time of year in San Marcos to be enjoyable for warm weather travelers. The average high during this season is between 69.2°F (20.7°C) and 63°F (17.2°C). On average, it rains or snows a fair amount: 3 to 5 times per month. These times of year are fairly slow with tourists.