Randolph, Minnesota Air Quality
Randolph has a median AQI of 9, earning an air quality grade of A+ — excellent air quality that ranks better than 98% of US cities. Air quality has been improving steadily over the past decade, a positive sign for residents. CO is the primary pollutant driving air quality conditions. In 2025, Randolph recorded 170 good air quality days (93% of monitored days).
Population: 461 • County: Dakota
Current AQI
Quick Facts
| Current AQI | 19 — Good |
| Air Quality Grade | A+ |
| Median AQI (2025) | 9 |
| vs. U.S. Cities | Better than 98% |
| Primary Pollutant | CO |
| Unhealthy Days/Year | 0 |
| 10-Year Trend | ↑ Improving |
| Data Source | EPA AQS (historical) · AirNow (live) |
Health Recommendation
Air quality is satisfactory, and air pollution poses little or no risk.
It's a great day to be active outside!
5-Day AQI Forecast
Last 90 Days
Current Pollutant Levels
Real-time data from EPA AirNow
Local Air Quality Context
Air quality data for Randolph is sourced from the Lakeville - Near Road monitoring area, located approximately 18 miles from city center. This EPA-certified station continuously tracks CO, the primary pollutant tracked in this area.
Randolph tends to see elevated PM2.5 readings during fall and winter months when temperature inversions trap pollutants near the surface. Wood burning, vehicle exhaust, and reduced wind speeds compound the effect. Residents with respiratory conditions should monitor forecasts closely between November and February.
AQI Trend (10 Years)
Air Quality Days by Year
Randolph Median AQI by Year
Annual EPA air quality data for Randolph — median AQI, day-category breakdown, and primary pollutant per year.
| Year | Median AQI | Good Days | Unhealthy Days | Max AQI | Primary Pollutant |
|---|---|---|---|---|---|
| 2025 | 9 | 170 | — | 68 | CO |
| 2024 | 38 | 258 | 1 | 152 | PM2.5 |
| 2023 | 49 | 184 | 10 | 185 | PM2.5 |
| 2022 | 34 | 286 | — | 82 | PM2.5 |
| 2021 | 39 | 252 | 3 | 157 | PM2.5 |
| 2020 | 40 | 260 | 1 | 135 | PM2.5 |
| 2019 | 36 | 269 | — | 90 | PM2.5 |
| 2018 | 41 | 257 | — | 92 | PM2.5 |
| 2017 | 37 | 267 | — | 85 | PM2.5 |
| 2016 | 34 | 289 | 1 | 135 | PM2.5 |
Source: EPA Air Quality System (AQS) annual summaries. "Unhealthy Days" includes Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, and Hazardous categories.
2025 Air Quality Summary
Primary Pollutant Days (2025)
Days when each pollutant was the primary driver of AQI. Learn about pollutants →
Frequently Asked Questions About Randolph Air Quality
What is the air quality in Randolph today?
The current AQI in Randolph is 19, rated "Good". Air quality is good — outdoor activity is safe for everyone today. Air quality is satisfactory, and air pollution poses little or no risk.
Is air quality in Randolph getting better or worse?
Air quality in Randolph has been improving. The median AQI has dropped 25 points (from 34 in 2016 to 9 in 2025), a positive trend for residents.
What is the most common air pollutant in Randolph?
CO is the primary air pollutant in Randolph, responsible for 92 days (51% of monitored days) in 2025. Carbon monoxide is primarily produced by vehicle exhaust and incomplete combustion.
How many unhealthy air days does Randolph have per year?
In 2025, Randolph recorded 93% good air quality days (170 days) out of 182 monitored days. There were 0 Unhealthy for Sensitive Groups days and 0 Unhealthy days (AQI above 100). The highest single-day AQI recorded was 68.
What air quality grade does Randolph receive?
Randolph receives an air quality grade of A+, placing it better than 98% of US cities. This is based on a median AQI of 9 in 2025, with 170 good air quality days. The EPA monitors air quality in this area continuously using certified monitoring stations.
Air Quality Grade
Better than 98% of US cities
Nearby Cities
Get AQI Alerts
Receive notifications when air quality changes in Randolph
National Rankings
See how Randolph compares to every other US city by air quality.
Best Air Quality Cities →All city rankingsRecommended Air Purifiers for Randolph
Carbon monoxide is Randolph's primary pollutant, typically from vehicle exhaust and incomplete combustion. Heavy activated carbon filtration is essential — HEPA alone does not capture CO.
Blueair Blue Pure 211+
High performance for large rooms with simple operation.
- ✓Good room size match
- ✓Recommended for your air quality
- ✓High performance
We may earn a commission from purchases
Other Great Options
Honeywell HPA300
Powerful workhorse for large rooms. Built to last.
Dyson Pure Cool TP04
Premium all-in-one air purifier and fan with advanced features.
Molekule Air Pro
Commercial-grade with patented PECO technology for destroying pollutants.
Not sure which air purifier is right for you?
Learn more about different types of air purifiers and how to choose the best one for your needs.
Read our complete buying guide →