Air quality in Hanover County, VA

EPA monitor readings, 2021 to 2025 (ozone only) · 110,000 people

Clean most daysOnly ozone is measured
Bad-air days a year
<1
day with an AQI over 100

1 bad-air day in 5 years of readings, 2021 to 2025. That's down from about 27 a year in the early 2000s. Hanover County is tied with 1 other Virginia county for the 4th fewest bad-air days of the 25 with monitors.

0days unhealthy for everyoneAQI over 150, a year
38AQI on a typical dayGood: fine for everyone
3bad-air days since 2016Too few to show a season
105worst day since 2016May 26, 2016, ozone
How to read the AQIThe EPA's air score runs from 0 to 500. Higher is worse. Over 100 counts as a bad-air day.
Typical day 38 (Good)Worst day 105 (Unhealthy for sensitive groups)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

Bad-air days by month in Hanover County

Bad air is rare here: 3 bad-air days in 10 years of daily readings since 2016, too few to show a season. Each tile is the average for that month.

Jan0
Feb0
Mar0
Apr0.2
May0.1
Jun0
Jul0
Aug0
Sep0
Oct0
Nov0
Dec0

The worst day since 2016 was May 26, 2016: AQI 105, from ozone.

What causes it

Ozone is the only pollutant measured here. The 3 bad-air days since 2016 were all ozone days, in April 2016, May 2016 and April 2023. Monitors here don't measure fine particles, so smoky days aren't in these counts.

CDC's model estimates about 0.0 days a year with high fine particles at the county's worst spot, 2018 to 2022. See the estimates on the map

CDC estimates by month, 2001 to 2022

The CDC's model counts bad-air days at the county's worst spot, from monitors and satellites. Particles (brown) fill the inside of the ring and ozone (blue) the outside.

JFMApril: 0.7 ozone days a yearAMay: 1.4 ozone days a yearMJune: 0.3 smoky days a yearJune: 2.9 ozone days a yearJJuly: 0.3 smoky days a yearJuly: 3.3 ozone days a yearJAugust: 0.6 smoky days a yearAugust: 2.8 ozone days a yearASeptember: 0.9 ozone days a yearSOctober: 0.1 ozone days a yearONDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Hanover County, 2001 to 2022
MonthFine particlesOzone
January00
February00
March00
April00.7
May01.4
June0.32.9
July0.33.3
August0.62.8
September00.9
October00.1
November00
December00

What helps in Hanover County

The air here is clean most days: 3 bad-air days in 10 years of daily readings. Wildfire smoke can still drift in from far away, so it's worth being ready.

Check tomorrow's forecast

AirNow posts an air quality forecast by ZIP code, usually the day before.

AirNow →

Keep a cheap backup

A box fan with a MERV 13 filter clamped to it cleans a room in a pinch.

Build one →

Keep one room clean on smoky days

Shut the windows and run an air purifier sized for the room.

Choosing a purifier →

For today's reading and tomorrow's forecast, check AirNow by ZIP code. Its fire and smoke map adds smoke plumes.

Smoky days are rare here, so a purifier is optional. If you want one for wildfire season anyway, see the 3 models we'd buy, each with a verified smoke rating.

Every year since 2001

Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2023, with 1 bad-air day.

0204060200145200520102015202020250204060200145201020202025
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Hanover County
YearBad-air daysOver 150
2001276
20024516
2003224
2004150
2005252
2006142
2007221
2008171
200910
2010141
2011100
201252
201400
201500
201620
201700
201800
201900
202000
202100
202200
202310
202400
202500

Hanover County and its neighbors

Bad-air days a year, 2021 to 2025. Virginia counties with monitors averaged about 2 bad-air days a year, weighted by population.

Henrico County1
Caroline County<1
Hanover County<1

Nearest counties with a full report: Chesterfield County, VA (under 1 bad-air days a year), Richmond City, VA (1 bad-air day a year).

Questions people ask about air in Hanover County

How often is the air bad in Hanover County?

From 2021 to 2025, monitors in Hanover County recorded almost no bad-air days a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2023, with 1 bad-air day.

What causes bad air in Hanover County?

The 3 bad-air days since 2016 were all ozone days, in April 2016, May 2016 and April 2023. Monitors here don't measure fine particles, so smoky days aren't in these counts.

Where can I see today's air quality in Hanover County?

AirNow, run by the EPA and its partners, shows the current AQI and tomorrow's forecast for your ZIP code. Its fire and smoke map adds smoke plumes. On a typical day the AQI in Hanover County is about 38, which is good, fine for everyone. Bad days are rare here, so check it when wildfire smoke is in the news.

About these numbers

Day counts come from the EPA's county air quality summaries, which take the worst reading across a county's monitors each day. Monitors here reported on about 240 days a year from 2021 to 2025; some run only in ozone season, so a few bad days can go uncounted. A county is large, and your street can be cleaner or worse. CDC's model, which estimates every county from monitors and satellites, gives the worst spot in Hanover County almost no high-particle days and almost no high-ozone days a year from 2018 to 2022.

Sources: EPA AirData county AQI summaries (2000 to 2025) and daily county AQI (2016 to 2025); CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone (2001 to 2022). Updated November 8, 2026.