Metro area air quality · 2025

Yuba City, CA

Median AQI 47 (Good). 63.2% of monitored days rated Good across this metro's EPA monitoring network.

47
Median AQI
63.2%
Good-air days
0
Unhealthy days
31%
Cleaner than US metros

Yuba City, CA posted a 2025 median AQI of 47 (Good) with 63.2% Good days

According to the U.S. EPA Air Quality System, the Yuba City, CA CBSA recorded a median AQI of 47 across 364 monitored days in 2025, with 63.2% rated Good and 0 unhealthy or worse. This is an annual metro comparison, not a live advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US metros
The Yuba City, CA CBSA's 63.2% Good-day share places it cleaner than 31% of US metros in 2025.
Closest median-AQI peer
Charleston-North Charleston, SC (60.3% Good, median AQI 47) is the closest nationwide median-AQI peer to Yuba City, CA.
2020–2025 Good-day shift
Yuba City, CA's Good-day share moved +16.6 points from 2020 to 2025 (median AQI -6).
Median AQI
Median AQI: 47

Aggregated from EPA Air Quality System (2025), 364 monitored days. EPA AQS →

The verdict

Yuba City, CA lands in the lower Good-day tercile (63.2% Good), a thinner clean-air share than most CBSA peers here. On the EPA scale the metro runs good, more polluted than the median US metro, with a median AQI of 47 and 63.2% of 364 monitored days in the Good band.

47
median AQI · Good
63.2%
days rated Good
31%
cleaner than US metros
100
worst single reading

No day crossed into the Unhealthy tier across the metro's monitors in 2025.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Yuba City, CA metro's Good-day share rose from 54.0% to 63.2% between the 2024 and 2025 EPA annual releases, a change of +9.2 percentage points.
  • Yuba City, CA metro's peak single-day AQI fell from 115 to 100 between the 2024 and 2025 EPA annual releases, a change of -15 points.

Compared against 361 monitored days in 2024 and 364 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Yuba City, CA lands in the lower Good-day tercile (63.2% Good), a thinner clean-air share than most CBSA peers here. Signature read: 63.2% Good-day share (low tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 47 over 364 measured days in 2025 (Good / Moderate). The monitored-day split lands at 230 Good (63%), 134 Moderate (37%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 64; the highest single-day reading hit 100 (Moderate).

Across 2020–2025, Good-day share shifted +16.6 points and median AQI moved -6 (improving). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Charleston-North Charleston, SC (60.3% good, AQI 47); Columbia, SC (58.1% good, AQI 47); Corsicana, TX (59.2% good, AQI 47).

Health effects of air pollution →

Air Quality Summary

Median AQI

47

Good

Good Days

63.2%

230 of 364 days

Max AQI

100

Moderate

Health Grade

Moderate

90th pct: 64

AQI Day Breakdown (2025)

Distribution of 364 monitored days across EPA AQI categories.

Good

230

63%

Moderate

134

37%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The Yuba City, CA metro area's air quality is rated Moderate based on 63.2% good air days. No unhealthy air days were recorded in 2025.

Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.

How does the Yuba City, CA metro compare?

How Yuba City, CA compares

Good-day share worse than typical
Yuba City, CA 63.2%
Charleston-North Charleston, SC 60.3%
Typical US metro 70.6%
Median AQI worse than typical
Yuba City, CA 47
Charleston-North Charleston, SC 47
Typical US metro 41
Unhealthy days / yr better than typical
Yuba City, CA 0
Charleston-North Charleston, SC 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is improving in the Yuba City, CA metro. Highest Good-day share: 2025 (63.2%, 230 of 364 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 162 173 13 53
2021 102 240 5 59
2022 154 205 0 52
2023 192 168 0 49
2024 195 166 0 49
2025 230 134 0 47

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Yuba City, CA (47).

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Yuba City, CA's 0 (independent of median AQI).

Frequently Asked Questions

How many unhealthy air days does Yuba City, CA have?
In 2025, the Yuba City, CA metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 100.
What is the air quality in the Yuba City, CA metro area?
The Yuba City, CA metro area has a median Air Quality Index (AQI) of 47, rated "Good." 63.2% of monitored days (230 out of 364) had good air quality in 2025.
Is air quality in Yuba City, CA getting better or worse?
Air quality in the Yuba City, CA metro is improving across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2025 at 63.2% (230 of 364 days). Lowest qualifying Good-day share: 2021 at 29.4% (102 of 347 days).
What does AQI 47 mean for health?
An AQI of 47 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
How does Yuba City, CA compare to other metro areas?
The Yuba City, CA metro has 63.2% good air days. Similar metros: Charleston-North Charleston, SC (60.3% good), Columbia, SC (58.1% good), Corsicana, TX (59.2% good).
What is the 90th percentile AQI for Yuba City, CA?
The 90th percentile AQI for the Yuba City, CA metro area is 64, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 100 (Moderate).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Yuba City, CA, 2025. See our methodology for how AQI, median, and coverage figures are computed.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary, Yuba City, CA · 2020–2025