Air Quality Info


Current Air Quality Health Advisories in place:

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AQI Animation -
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air quality index

AQI Forecast

Nevada County

This forecast is for the pollutant: ozone (O3)

04 / 22 / 17 Sat 65 50
04 / 23 / 17 Sun 65 49
04 / 24 / 17 Mon 70 43
04 / 25 / 17 Tue 70 50
04 / 26 / 17 Wed 40 39
04 / 27 / 17 Thu 75 74
04 / 28 / 17 Fri 75
04 / 29 / 17 Sat 80
04 / 30 / 17 Sun 80
05 / 01 / 17 Mon 80
05 / 02 / 17 Tue 85

Well, things are warming up and apparently we are starting to dry out. Hard to predict what the month of May will bring us in terms of weather. But I expect we will see ozone values in the Moderate range for the foreseeable future.

In October of 2015 the EPA modified the National Ambient Air Quality Standard (NAAQS) for ozone. The old standard was 75 ppb (8 hour average). The new standard is now 70 ppb (8 hour average). Since the AQI values are based on the NAAQS, that means the AQI values are going to be a little higher this year even if the ozone values are identical to last year. Hence, we are going to have more days in the Moderate range in 2016, and even more days in the Unhealthy for Sensitive Groups range.

You may or may not have noticed, but one of the things that is unique and special about my ozone AQI forecast is that unlike almost everybody else, I let you see what the forecast was. That allows the user an opportunity to see how accurate my forecast is (or is not). That is a feature I wish the weather web sites and other AQI forecasters would add to their web pages.For Western Nevada County only, check out Ozone Maps at

To check out PM2.5 data for both Eastern and Western Nevada County, click here.  Be sure to set PM2.5 for the Parameter, and in Step 3 set the county to “Nevada”

Plumas County

To Check current PM 2.5 conditions click here. Be sure to set PM2.5 for the Parameter, and in Step 3 set the county to “Plumas”