Lake San Marcos, CA Weather - Forecast & Monthly Averages

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TEMPERATURE
HUMIDITY
PRESSURE
WIND COND.

Weather Quick Facts

The highest monthly average temperature in Lake San Marcos for August is 70.2 degrees
The lowest monthly average temperature in Lake San Marcos for December is 55.8 degrees
The most monthly precipitation in Lake San Marcos occurs in December with 2.7 inches
The air quality index in Lake San Marcos is 52% worse than the national average
The pollution index in Lake San Marcos is 1581% worse than the national average

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Lake San Marcos Average Temperature

In the event that the weather data was unavailable for this city, estimates based upon nearby cities were used.
Month	Temp. _(min)	Temp. _(max)	Temp. _(avg)	Precipitation
January	48°F	67°F	56°F	1.8"
February	49°F	66°F	56°F	2.0"
March	51°F	67°F	58°F	1.1"
April	54°F	68°F	60°F	0.7"
May	58°F	69°F	63°F	0.4"
June	61°F	71°F	65°F	0.0"
July	65°F	75°F	69°F	0.1"
August	66°F	76°F	70°F	0.1"
September	64°F	77°F	70°F	0.1"
October	59°F	75°F	67°F	0.5"
November	53°F	71°F	61°F	1.0"
December	48°F	66°F	56°F	2.7"

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Lake San Marcos air quality index & pollution index

In the event that the air quality/pollution data was unavailable for this city, estimates based upon nearby cities were used.
Index	Lake San Marcos	California	National
Air quality index	64	55	42
Pollution index	45,820,500	10,473,190	2,726,193

Lake San Marcos air quality

Measurement	Total
Days measured	365
Days with good air quality	87
Days with moderate air quality	253
Days w/ poor A.Q. for sensitive groups	23
Days with unhealthy air quality	2

Air quality details

Pollutant	Total
Arsenic	1.130%
Benzene	0.410%
Carbon Tetrachloride	0.030%
Lead	0.600%
Mercury	0.080%

Average monthly Lake San Marcos temperature with heat index

Lake San Marcos monthly precipitation with daily maximum

Lake San Marcos monthly snow depth with daily maximum

Lake San Marcos monthly wind speed information

Nearby cities with good air quality

City	Population	Air Quality Index	National Avg.
Camp Pendleton North, CA	7,885	64	28.0%
Carlsbad, CA	114,411	64	28.0%
Fairbanks Ranch, CA	2,929	64	28.0%
Solana Beach, CA	13,301	64	28.0%
Camp Pendleton South, CA	16,618	64	28.0%
Lake San Marcos, CA	3,957	64	28.0%

Cities with similar population

City	Population	Air Quality Index	National Avg.
Southgate, KY	3,957	54	8.0%
Level Green, PA	3,957	56	12.0%
Grand Mound, WA	3,957	20	60.0%
Ashland, MO	3,956	38	24.0%
Weaverville, NC	3,956	44	12.0%
Lake San Marcos, CA	3,957	64	28.0%

Source: The Lake San Marcos, CA weather data displayed above is derived from the NOAA (National Oceanic and Atmospheric). Air quality and pollution data is derived from the EPA (United States Environmental Protection Agency). Air quality and pollution levels measured in a particular area may not be representative of the entire county.