San Marcos, CA Weather & Climate Normals
San Marcos's real weather, in one number
San Marcos, CA scores 82/100 on this site's reading of NOAA's own 30-year normals: very mild year-round. Many months fall in a comfortable temperature range with limited snow or seasonal extremes. 10 of the year's 12 months average between 55 and 75°F, the range this site counts as mild.
San Marcos's hottest and coldest months
San Marcos's hottest month is Aug, averaging 77°F; its coldest is Dec, averaging 56°F, a 21.3°F swing across the year, a middling gap by national standards.
Rain and snow in San Marcos
San Marcos averages 14.52in of precipitation a year across roughly 41 days with measurable rain or snow, and 0in of snow a year.
Where San Marcos ranks
San Marcos ranks 93 of 4876 US cities in this dataset for comfort score, and 93 of 429 within CA. About 96,620 people live there.
If you need tomorrow's forecast, not the 30-year average
Everything above is a 30-year average from ESCONDIDO #2, CA US, 4.7 miles from San Marcos, not a prediction for any specific day.
More on how this is worked out
How the comfort score is calculated · Why some cities show no snow or rain figure