Today | Weather | Tuesday, March 17, 2026
Active Weather Warnings

Weather in Downey, California

12:21 AM
Now
Night
70° F
Feels Like 68°
Precipitation 0 %
Wind 4 mph
Humidity 55 %
Today
Hot Day
Day 97°
Night 61°
Precipitation 0 %
Wind 6 mph
UV Index (0 - 11+) 6

Downey Weather Forecast Updated

Last updated on
Weather Forecast History
Last Year's Weather on This Day (March 17, 2025)
Partly Sunny with Showers

Day

64°

Night

46°

Wind

7 mph

UV Index

6

Precipitation

40 %

Air Quality in Downey

NOW
56 AQI
Moderate air quality Dominant pollutant: PM2.5

Pollutant Concentrations:

PM2.5 14.75 µg/m³
PM10 22.08 µg/m³
O3 0.047 ppm
NO2 0.3 ppb
SO2 0.1 ppb
CO 0.12 ppm
NH3 0 µg/m³
NO 0 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is acceptable; however, for some pollutants, there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.

Show raw pollutant concentrations (µg/m³)
PM2.514.75 µg/m³
PM1022.08 µg/m³
O392.16 µg/m³
NO20.56 µg/m³
SO20.39 µg/m³
CO141.35 µg/m³
NH30 µg/m³
NO0 µg/m³

Weather Alerts and Warnings for Downey

Severe Future Likely

Extreme Heat Watch

Extreme Heat Watch issued March 15 at 12:07AM PDT until March 20 at 8:00PM PDT by NWS Los Angeles/Oxnard CA
Mar 16, 8:00 PM Mar 20, 8:00 PM
WHAT: For the Heat Advisory, temperatures of 82 to 98 expected..
For the Extreme Heat Watch, dangerously hot conditions with
temperatures of 90 to 104 are possible.

WHERE: A portion of southwest California.

WHEN: For the Heat Advisory, from 10 AM to 8 PM PDT Monday. For
the Extreme Heat Watch, from Monday evening through Friday evening.

IMPACTS: There is a high risk for dangerous heat illness for
anyone, especially for the very young, the very old, those without
air conditioning, and those active outdoors. There is a high risk
for heat illness for sensitive populations including the very
young, the very old, those without air conditioning, and those
active outdoors.
+ Read More
Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.
Updated: Mar 15, 10:13 AM Source: NWS Alert
Severe Expected Likely

Extreme Heat Warning

Extreme Heat Warning issued March 16 at 4:47PM PDT until March 20 at 8:00PM PDT by NWS Los Angeles/Oxnard CA
Mar 17, 10:00 AM Mar 20, 8:00 PM
WHAT: For the Heat Advisory, temperatures between 90 and 98
expected. For the Extreme Heat Warning, dangerously hot conditions
with temperatures between 96 and 104 expected.

WHERE: A portion of southwest California.

WHEN: For the Heat Advisory, until 10 AM PDT Tuesday. For the
Extreme Heat Warning, from 10 AM Tuesday to 8 PM PDT Friday.

IMPACTS: There is a high risk for dangerous heat illness for
anyone, especially for the very young, the very old, those without
air conditioning, and those active outdoors.

ADDITIONAL DETAILS: Warm overnight low temperatures will
contribute to the heat risk, especially in the mountain and
foothill locations.
+ Read More
Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke.
Updated: Mar 16, 11:19 PM Source: NWS Alert
Moderate Expected Likely

Heat Advisory

Heat Advisory issued March 16 at 4:47PM PDT until March 17 at 10:00AM PDT by NWS Los Angeles/Oxnard CA
Mar 16, 4:47 PM Mar 17, 10:00 AM
WHAT: For the Heat Advisory, temperatures between 90 and 98
expected. For the Extreme Heat Warning, dangerously hot conditions
with temperatures between 96 and 104 expected.

WHERE: A portion of southwest California.

WHEN: For the Heat Advisory, until 10 AM PDT Tuesday. For the
Extreme Heat Warning, from 10 AM Tuesday to 8 PM PDT Friday.

IMPACTS: There is a high risk for dangerous heat illness for
anyone, especially for the very young, the very old, those without
air conditioning, and those active outdoors.

ADDITIONAL DETAILS: Warm overnight low temperatures will
contribute to the heat risk, especially in the mountain and
foothill locations.
+ Read More
Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke.
Updated: Mar 16, 11:19 PM Source: NWS Alert