San Marcos, CA Weather
San Marcos, CA climate is warm during summer when temperatures tend to be in the 70's and cool during winter when temperatures tend to be in the 50's.
The warmest month of the year is August with an average maximum temperature of 89.10 degrees Fahrenheit, while the coldest month of the year is December with an average minimum temperature of 41.60 degrees Fahrenheit.
Temperature variations between night and day tend to be moderate during summer with a difference that can reach 27 degrees Fahrenheit, and moderate during winter with an average difference of 25 degrees Fahrenheit.
The annual average precipitation at San Marcos is 15.10 Inches. Rainfall in is fairly evenly distributed throughout the year. The wettest month of the year is January with an average rainfall of 3.37 Inches.
Weather Data
Current Conditions
|
Fog And Mist, 63°F | Humidity: 87% | Dewpoint: 59°F |
| Wind Speed: CALM | Heat Index: 63°F | ||
| Barometer: 29.90 in. | Wind Chill: 63°F |
Weather Forecast
 | Tonight: Mostly clear. Lows 60 to 69. Light winds. | |
| Lo: 65°F | ||
 | Hi: 88°F | Friday: Mostly sunny. Highs 85 to 90 in the western valleys to 95 to 100 near the foothills. Light winds becoming west 15 mph in the afternoon. |
| Lo: 68°F | ||
| Hi: 92°F | Saturday: Sunny. Highs 89 to 94 in the western valleys to 98 to 103 near the foothills. Light winds. |
| Lo: 65°F | ||
| Hi: 83°F | Sunday: Mostly sunny. Patchy fog in the morning. Highs 80 to 85 in the western valleys to 87 to 92 near the foothills. |
| Lo: 58°F | ||
| Hi: 78°F | Labor day: Partly cloudy in the morning...Becoming sunny. Patchy fog in the morning. Highs 75 to 80 in the western valleys to 81 to 86 near the foothills. |
| Lo: 55°F | ||
| Hi: 75°F | Tuesday: Mostly cloudy in the morning...Becoming mostly sunny. Patchy fog in the morning. Highs 72 to 77 in the western valleys to 76 to 81 near the foothills. |
| Lo: 54°F | ||
| Hi: 73°F | Wednesday: Cloudy in the morning...Becoming mostly sunny. Patchy fog in the morning. Highs 70 to 75 in the western valleys to 74 to 79 near the foothills. |
| Lo: 53°F |
Moon, Sunrise and Sunset
 |
Moon Phase: Waning Crescent Moon | Civil Twilight: 5:58 AM PDT |
Sunrise: 6:23 AM PDT |
| Sunset: 7:11 PM PDT |
Civil Twilight: 7:37 PM PDT |
Normal Climate
Normal Temperatures
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Max °F | 68.5 | 69.4 | 70.4 | 74.8 | 77.5 | 83.6 | 88.6 | 89.1 | 86.9 | 81.0 | 73.9 | 69.2 | 77.7 |
| Mean °F | 55.5 | 57.0 | 58.6 | 62.3 | 66.0 | 70.8 | 75.1 | 76.2 | 74.0 | 68.0 | 60.1 | 55.4 | 64.9 |
| Min °F | 42.5 | 44.5 | 46.8 | 49.8 | 54.4 | 57.9 | 61.5 | 63.2 | 61.1 | 54.9 | 46.3 | 41.6 | 52.0 |
Normal Precipitation
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Inch | 3.37 | 3.16 | 3.30 | 1.04 | 0.27 | 0.11 | 0.07 | 0.02 | 0.22 | 0.44 | 1.32 | 1.78 | 15.10 |
