Altadena, CA Weather - Forecast & Monthly Averages

Get 300+ Local Insights for Any Address in Altadena, CA

Get Access to 300+ Local Data Points

TEMPERATURE
HUMIDITY
PRESSURE
WIND COND.

Weather Quick Facts

The highest monthly average temperature in Altadena for August is 75.3 degrees
The lowest monthly average temperature in Altadena for December is 54.9 degrees
The most monthly precipitation in Altadena occurs in January with 3.3 inches
The air quality index in Altadena is 71% worse than the national average
The pollution index in Altadena is 5017% worse than the national average

Compare Altadena, CA Weather

Compare Neighborhoods & Addresses

Why stop at city-to-city? With Local Insights, you can compare neighborhoods, zip codes, or even exact addresses. Access 300+ hyperlocal data points—from schools and crime to housing and amenities—to see which area is the better fit.

UNLOCK FULL COMPARISON →

Write a review to give others more information about this area.

See all Altadena poll results

Altadena 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	45°F	69°F	56°F	3.3"
February	46°F	70°F	57°F	2.5"
March	49°F	73°F	60°F	2.0"
April	52°F	75°F	62°F	0.6"
May	56°F	78°F	65°F	0.2"
June	60°F	83°F	70°F	0.0"
July	65°F	89°F	75°F	0.0"
August	65°F	90°F	75°F	0.0"
September	63°F	89°F	74°F	0.2"
October	57°F	82°F	68°F	0.5"
November	50°F	76°F	62°F	0.6"
December	44°F	68°F	55°F	2.1"

The best places in California

Here are the best places to live in California

Most Dangerous Cities In The US

See the best places to live in Altadena

These are the 10 cheapest cities in California

Altadena 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	Altadena	California	National
Air quality index	72	55	42
Pollution index	139,490,000	10,473,190	2,726,193

Altadena air quality

Measurement	Total
Days measured	365
Days with good air quality	66
Days with moderate air quality	208
Days w/ poor A.Q. for sensitive groups	62
Days with unhealthy air quality	28

Air quality details

Pollutant	Total
Arsenic	0.200%
Benzene	0.950%
Carbon Tetrachloride	0.080%
Lead	1.320%
Mercury	0.440%

Average monthly Altadena temperature with heat index

Altadena monthly precipitation with daily maximum

Altadena monthly snow depth with daily maximum

Altadena monthly wind speed information

Nearby cities with good air quality

City	Population	Air Quality Index	National Avg.
Baldwin Park, CA	75,659	72	44.0%
Hacienda Heights, CA	55,386	72	44.0%
South San Jose Hills, CA	19,104	72	44.0%
West Puente Valley, CA	23,555	72	44.0%
La Crescenta-Montrose, CA	20,171	72	44.0%
Altadena, CA	43,037	72	44.0%

Cities with similar population

City	Population	Air Quality Index	National Avg.
Freeport, NY	42,993	51	2.0%
DeKalb, IL	42,961	42	16.0%
Goose Creek, SC	42,944	38	24.0%
Fond du Lac, WI	42,944	36	28.0%
Winter Haven, FL	42,933	36	28.0%
Altadena, CA	43,037	72	44.0%

Source: The Altadena, 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.