San Marcos Weather in September

September in San Marcos brings very high temperatures, with highs of 33°C (91°F) and nights dropping to 20°C (68°F). Rainfall is on the higher side this month, averaging around 110 mm (4.3 in), so keep a rain jacket handy.

Rainfall in San Marcos in September

Historically, the month has about 10 days of rain, averaging 110 mm (4.3 in) in total. When it rains this month, it tends to come down fairly heavily. Showers can be substantial even if they don't last all day.

Temperature in San Marcos in September

Daytime temperatures in San Marcos reach 33°C (91°F) in September, dropping to 20°C (68°F) at night. Indoor breaks or shaded spots can make the warmer part of the day much more comfortable. With overnight lows of 20°C (68°F), evenings stay pleasantly warm.

Sunshine in San Marcos in September

There are approximately 234 hours of sunshine this month, resulting in mostly clear days.

September in San Marcos can still be great, but if you prefer pleasant temperatures along with dry and sunny conditions, our weather planner can help you explore other options in the world.

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For a detailed overview over the year and the best time to visit the United States of America, check out our San Marcos's climate page.

San Marcos Temperature in September

Min Temperature 20°C (68°F)  

Max Temperature 33°C (91°F)  

Chance of Rain 32%  

Precipitation 110 mm (4.3 in)  

Rainy days 10 days  

Humidity 68% *  

Sunshine 234 hours *  

Percentage Sunshine 63% *  

* Data from: Austin, the United States of America (51 KM, 32 Miles).

What to Wear in San Marcos in September

Warm but pleasant conditions in San Marcos in September. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. Expect heavy rainfall, so bring good rain protection and waterproof bags. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.

What To Do in San Marcos in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

9/10

Cycling

7/10

Walking

7/10

Camping

6/10

Outdoor sports

7/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United States of America, check out our San Marcos's climate page.

More climate data for San Marcos

Temperature Rainfall Sunshine Humidity

See the full San Marcos climate overview or explore weather in the United States of America.