Median AQI
33
Good
Michigan · County air quality · 2025
Manistee County, Michigan
Median AQI 33 (Good). 79.5% of monitored days rated Good, direct from EPA Air Quality System stations.
- 33
- Median AQI
- 79.5%
- Good-air days
- 3
- Unhealthy days
- 55%
- Cleaner than US counties
Manistee County's 2025 annual median AQI is 33 (Good), with 79.5% Good days
According to the U.S. EPA Air Quality System, Manistee County, Michigan posted a 2025 median AQI of 33 (Good) across 361 monitored days, with 79.5% rated Good and 3 unhealthy or worse. This is an annual comparison, not today's advisory.
Data source EPA Air Quality System (AQS)
- Cleaner than US
- Manistee County's 79.5% Good-day share places it cleaner than 55% of US counties in 2025.
- Closest median-AQI peer
- Apache County (86.2% Good, median AQI 33) is the closest nationwide median-AQI peer to Manistee County.
- 2020–2025 trend
- Manistee County's floor-qualifying Good-day share is worsening from 2020 to 2025 (91.4% → 79.5%).
- Median AQI
- Median AQI: 33
The verdict
According to EPA Air Quality System monitoring data, Manistee County's air is good on balance, cleaner than the median US county, a median AQI of 33 with 79.5% of 361 monitored days in the Good band, driven mainly by PM2.5.
- 33
- median AQI · Good
- 79.5%
- days rated Good
- PM2.5
- main pollutant
- 55%
- cleaner than US counties
3 days reached Unhealthy or worse; the worst single reading hit AQI 167.
Annual release change
What changed in the 2025 EPA annual release
- Manistee County's peak single-day AQI rose from 105 to 167 between the 2024 and 2025 EPA annual releases, a change of +62 points.
- Manistee County's Unhealthy-category days rose from 0 to 3 between the 2024 and 2025 EPA annual releases, a change of +3 days.
- Manistee County's Good-day share fell from 81.2% to 79.5% between the 2024 and 2025 EPA annual releases, a change of -1.7 percentage points.
Data updated August 2026
- Good · 287 d · 79.5%
- Moderate · 65 d · 18.0%
- USG · 6 d · 1.7%
- Unhealthy · 3 d · 0.8%
How did Manistee County's air break down in 2025?
Across 361 monitored days, 287 fell in the Good band (AQI 0–50) and 3 reached Unhealthy or worse. The worst single day peaked at AQI 167 (Unhealthy).
EPA AQS →Air quality data from EPA Air Quality System (2025). 361 days monitored. Median AQI: 33 (Good).
Insights: Manistee County, Michigan. EPA monitors recorded a median Air Quality Index of 33 across 361 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 287 (80%) fell in the Good band (AQI 0–50), 65 (18%) registered Moderate readings, and 6 (2%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 65, while the worst single-day peak hit 167 (Unhealthy). Residents averaged about 23.9 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as PM2.5 (208 days), Ozone (153 days). Across the 2020–2025 trend window, the share of monitored days rated Good shifted by -11.9 points (measured against 139 monitored days in 2020 and 361 in 2025, so raw day counts are not comparable) and the median AQI moved +3 points, placing the multi-year trajectory at worsening. The annual record contains 3 days at Unhealthy or worse. On those days, the EPA recommends that sensitive groups limit prolonged outdoor exertion. Nearby counties show comparable readings: Allegan (63.9% good, AQI 44); Bay (70.4% good, AQI 39); Benzie (91.1% good, AQI 35); Berrien (80.9% good, AQI 41); Cass (85.3% good, AQI 40); Clinton (90.2% good, AQI 39).
Air Quality Summary
Good Days
79.5%
287 of 361 monitored days
4.5pp vs 75% target
Max AQI Recorded
167
Unhealthy
Health Grade
Good
90th-pct AQI 65
Manistee County, Good days share 79.5%
National avg
Share of monitored days at AQI 0-50 (Good band).
Manistee County, Unhealthy-or-worse share 8.3%
National avg
Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).
AQI Day Breakdown (2025)
Distribution of 361 monitored days across EPA AQI categories.
Good
287
80%
Moderate
65
18%
USG
6
2%
Unhealthy
3
1%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Manistee County.
- PM2.5 · 208 days · 57.6%
- Ozone · 153 days · 42.4%
Health Impact Assessment
Good
Manistee County's air quality is rated Good based on 79.5% good air days. There were 3 unhealthy days in 2025 when outdoor activity should be limited.
Air quality is acceptable most days, but 6 days reached "Unhealthy for Sensitive Groups" (AQI 101-150) and peak AQI reached 167. Sensitive groups should monitor real-time conditions at AirNow.gov.
The dominant pollutant is PM2.5, driving AQI on 208 of 361 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Manistee County. Highest Good-day share: 2020 (91.4%, 127 of 139 monitored days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 127 | 12 | 0 | 0 | 30 | 80 |
| 2021 | 218 | 48 | 3 | 0 | 38 | 115 |
| 2022 | 235 | 29 | 2 | 1 | 35 | 156 |
| 2023 | 244 | 57 | 7 | 1 | 39 | 161 |
| 2024 | 125 | 28 | 1 | 0 | 33 | 105 |
| 2025 | 287 | 65 | 6 | 3 | 33 | 167 |
How does Manistee County compare?
How Manistee County compares
Good-day share better than typical
Manistee County 79.5%
Apache County, Arizona 86.2%
Typical US county 76.0%
Median AQI better than typical
Manistee County 33
Apache County, Arizona 33
Typical US county 39
Unhealthy days / yr worse than typical
Manistee County 3
Apache County, Arizona 0
Typical US county 1
Counties with a similar median AQI
Nationwide peers within about the same annual median AQI as Manistee County (33), not geographic neighbors.
Apache County, Arizona
Median AQI 33 · 86.2% Good-day share
Ascension County, Louisiana
Median AQI 33 · 95.6% Good-day share
Carlton County, Minnesota
Median AQI 33 · 82.8% Good-day share
Clark County, Illinois
Median AQI 33 · 93.8% Good-day share
Clark County, Washington
Median AQI 33 · 82.7% Good-day share
Clay County, Alabama
Median AQI 33 · 81.1% Good-day share
Same primary pollutant: PM2.5
PM2.5 led the AQI on the most monitored days here. These peers share that driver and the closest Good-day share (a second relationship type beyond median-AQI neighbors).
Tangipahoa County, Louisiana
79.5% Good-day share · median AQI 41
Martin County, Florida
79.5% Good-day share · median AQI 40
Salem City County, Virginia
79.7% Good-day share · median AQI 31
Grant County, Washington
79.7% Good-day share · median AQI 28
Ravalli County, Montana
79.2% Good-day share · median AQI 21
Anchorage County, Alaska
79.2% Good-day share · median AQI 26
Michigan counties on the map
Geographic containment only, other monitored counties in Michigan, independent of AQI or pollutant match.
What Manistee County's air means for you
On most days the air here is fine, but PM2.5 drives 3 unhealthy-or-worse days a year that sensitive groups should plan around.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-PM2.5 days, the guide explains what a median of 33 means for exposure. Health guidance
- See how Manistee County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Manistee County with its Michigan neighbours before drawing a conclusion about the region. All of Michigan
Based on 361 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.
Keep exploring the annual AQI record
Air-quality reading list
Frequently Asked Questions
What is the air quality in Manistee County, Michigan? ▼
Manistee County has a median Air Quality Index (AQI) of 33, rated "Good." 79.5% of monitored days (287 out of 361) had good air quality in 2025.
What is the main pollutant in Manistee County? ▼
The primary pollutant in Manistee County is Fine Particles (PM2.5), which was the main AQI driver on 208 days (58% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Manistee County have? ▼
In 2025, Manistee County recorded 3 unhealthy air days (3 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 167.
Is the air quality in Manistee County getting better or worse? ▼
Air quality in Manistee County is worsening across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2020 at 91.4% (127 of 139 days). Lowest qualifying Good-day share: 2023 at 79.0% (244 of 309 days).
What does AQI 33 mean for health? ▼
Manistee County's median AQI of 33 falls in the "Good" category. See the AQI category guide for what each range means for health.
How does Manistee County compare to other counties in Michigan? ▼
Manistee County has 79.5% good air days. Nearby counties in Michigan: Allegan (63.9% good), Bay (70.4% good), Benzie (91.1% good), Berrien (80.9% good), Cass (85.3% good), Clinton (90.2% good).
What is the 90th percentile AQI in Manistee County? ▼
The 90th percentile AQI for Manistee County is 65, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 167 (Unhealthy).
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.
Informational only, not professional advice. Data from EPA AQS. See our disclaimer. Spotted a figure that looks wrong? Report a correction.
Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Manistee County, Michigan · 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.