Metro area air quality · 2025

Kahului-Wailuku-Lahaina, HI

Median AQI 21 (Good). 98.1% of monitored days rated Good across this metro's EPA monitoring network.

21
Median AQI
98.1%
Good-air days
0
Unhealthy days
98%
Cleaner than US metros

Kahului-Wailuku-Lahaina, HI posted a 2025 median AQI of 21 (Good) with 98.1% Good days

According to the U.S. EPA Air Quality System, the Kahului-Wailuku-Lahaina, HI CBSA recorded a median AQI of 21 across 360 monitored days in 2025, with 98.1% 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 Kahului-Wailuku-Lahaina, HI CBSA's 98.1% Good-day share places it cleaner than 98% of US metros in 2025.
Closest median-AQI peer
Othello, WA (90.5% Good, median AQI 21) is the closest nationwide median-AQI peer to Kahului-Wailuku-Lahaina, HI.
2020–2025 Good-day shift
Kahului-Wailuku-Lahaina, HI's Good-day share moved -0.2 points from 2020 to 2025 (median AQI +0).
Median AQI
Median AQI: 21

Aggregated from EPA Air Quality System (2025), 360 monitored days. EPA AQS →

The verdict

The Kahului-Wailuku-Lahaina, HI metro runs good on the EPA scale, among the cleanest 10% of US metros, a median AQI of 21 with 98.1% of 360 monitored days in the Good band.

21
median AQI · Good
98.1%
days rated Good
98%
cleaner than US metros
69
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
  • Kahului-Wailuku-Lahaina, HI metro's peak single-day AQI fell from 101 to 69 between the 2024 and 2025 EPA annual releases, a change of -32 points.
  • Kahului-Wailuku-Lahaina, HI metro's Good-day share fell from 100.0% to 98.1% between the 2024 and 2025 EPA annual releases, a change of -1.9 percentage points.

Compared against 363 monitored days in 2024 and 360 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

Insights: Kahului-Wailuku-Lahaina, HI metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 21 over 360 measured days in 2025, which corresponds to a Good band and a Excellent metro-wide health grade. The monitored-day split lands at 353 Good days (98%), 7 Moderate (2%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 32 while the highest single-day reading hit 69 (Moderate). Metro residents averaged roughly 29.4 clean-air days per 30-day window across the reporting year.

Across the 2020–2025 trend window, the share of monitored days rated Good shifted by -0.2 points and the median AQI moved +0 points, which classifies the multi-year trajectory as stable. The metro recorded no Unhealthy-tier days in this annual dataset. Metros with comparable AQI profiles include Othello, WA (90.5% good, AQI 21); Palatka, FL (95.6% good, AQI 21); Aberdeen, WA (97.3% good, AQI 22).

Air Quality Summary

Median AQI

21

Good

Good Days

98.1%

353 of 360 days

Max AQI

69

Moderate

Health Grade

Excellent

90th pct: 32

AQI Day Breakdown (2025)

Distribution of 360 monitored days across EPA AQI categories.

Good

353

98%

Moderate

7

2%

USG

0

0%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Excellent

The Kahului-Wailuku-Lahaina, HI metro area's air quality is rated Excellent based on 98.1% 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 Kahului-Wailuku-Lahaina, HI metro compare?

How Kahului-Wailuku-Lahaina, HI compares

Good-day share better than typical
Kahului-Wailuku-Lahaina, HI 98.1%
Othello, WA 90.5%
Typical US metro 70.6%
Median AQI better than typical
Kahului-Wailuku-Lahaina, HI 21
Othello, WA 21
Typical US metro 41
Unhealthy days / yr better than typical
Kahului-Wailuku-Lahaina, HI 0
Othello, WA 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Kahului-Wailuku-Lahaina, HI metro. Highest Good-day share: 2024 (100.0%, 363 of 363 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 343 6 0 21
2021 361 2 0 21
2022 357 4 0 21
2023 344 2 1 20
2024 363 0 0 21
2025 353 7 0 21

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Kahului-Wailuku-Lahaina, HI (21).

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Kahului-Wailuku-Lahaina, HI's 0 (independent of median AQI).

More Air Quality Data

Explore EPA air quality rankings and guides across U.S. metros and counties.

Air Quality Guides

Frequently Asked Questions

What is the air quality in the Kahului-Wailuku-Lahaina, HI metro area?
The Kahului-Wailuku-Lahaina, HI metro area has a median Air Quality Index (AQI) of 21, rated "Good." 98.1% of monitored days (353 out of 360) had good air quality in 2025.
How many unhealthy air days does Kahului-Wailuku-Lahaina, HI have?
In 2025, the Kahului-Wailuku-Lahaina, HI metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 69.
Is air quality in Kahului-Wailuku-Lahaina, HI getting better or worse?
Air quality in the Kahului-Wailuku-Lahaina, HI metro is stable across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2024 at 100.0% (363 of 363 days). Lowest qualifying Good-day share: 2025 at 98.1% (353 of 360 days).
What does AQI 21 mean for health?
An AQI of 21 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
What is the 90th percentile AQI for Kahului-Wailuku-Lahaina, HI?
The 90th percentile AQI for the Kahului-Wailuku-Lahaina, HI metro area is 32, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 69 (Moderate).
How does Kahului-Wailuku-Lahaina, HI compare to other metro areas?
The Kahului-Wailuku-Lahaina, HI metro has 98.1% good air days. Similar metros: Othello, WA (90.5% good), Palatka, FL (95.6% good), Aberdeen, WA (97.3% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2025. 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 files (metro-level) · 2020–2025

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Every figure on PlainAirData is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.