Nevada air quality

Washoe County, Nevada Air Quality

Washoe County40.665, -119.664

The nearest reporting area, Portola, measured an index of 21 this hour, which is Good. Northern Sierra AQMD forecasts Good for Portola today and Good tomorrow.

Measured now
21 · Good
Today
39 · Good
Tomorrow
22 · Good
Pollutant
PM2.5

Fine particles on the map

Forecast fine particulate matter from NOAA’s National Air Quality Forecast Capability over Washoe County, Nevada. Open it for the live map, where it pans and zooms.

Forecast fine particulate matter from NOAA’s National Air Quality Forecast Capability over Washoe County, Nevada Open the live map with the particulate forecast

Map layer from NOAA National Air Quality Forecast Capability. Boundaries from the Iowa Environmental Mesonet.

Alerts in force

An Air Quality Alert is issued by the National Weather Service on behalf of a state or local agency when pollution is expected to reach a level that harms health. An Air Stagnation Advisory means the air will not move enough to clear what is already in it.

None are in force near Washoe County right now. All Nevada warnings.

Now

Good

Reporting area
Portola, CA, 73 miles away
Reported by
Northern Sierra AQMD
Area index
21 · Good

Measured, not modeled. AirNow observations are preliminary until the operating agency certifies them, which happens months later.

Today and tomorrow

Northern Sierra AQMD's own forecast for Portola, written by a forecaster rather than read off a model.

DayCategoryIndexPollutant
TodayGood39PM2.5
TomorrowGood22PM2.5
Saturday, September 26Good28PM2.5
Sunday, September 27Good28PM2.5
Monday, September 28Good39PM2.5

The forecaster’s discussion

Written by Northern Sierra AQMD for Portola and filed with AirNow.

Wednesday, September 23: Light to moderate west-southwesterly winds will gradually disperse pollutants, and high temperatures in the low-80s will be sufficient for atmospheric mixing. As a result, AQI levels will be Good. Thursday, September 24 and Friday, September 25: As an upper-level trough of low pressure passes to the north, gusty southwesterly surface winds will develop in Portola each afternoon, effectively dispersing pollutants and keeping AQI levels Good on both days. Saturday and Sunday, moderate to gusty southwesterly surface winds will redevelop each afternoon as the next trough of low pressure aloft passes over the region. These winds will effectively disperse pollutants, yielding continued Good AQI levels on both days. Monday, calm to light winds will inhibit pollutant dispersion. Furthermore, a morning temperature inversion will trap pollutants near the ground. However, low pollutant carryover from the prior days will keep AQI levels Good in the Portola region.

Hour by hour

NOAA’s National Air Quality Forecast Capability, bias-corrected against monitors, for this town’s own coordinate. The worst hour ahead is an index of 45, Good, around Thu, 11:00 PM PDT, from the run issued Wed, 8:00 PM PDT. This is a model, not a measurement.

HourIndexCategoryPM2.5Ozone
Wed, 7:00 AM PDT22Good4.1
Wed, 8:00 AM PDT23Good4.3
Wed, 9:00 AM PDT23Good4.5
Wed, 10:00 AM PDT24Good4.9
Wed, 11:00 AM PDT26Good5.1
Wed, 12:00 PM PDT26Good4.5
Wed, 1:00 PM PDT32Good4.335.2
Wed, 2:00 PM PDT33Good3.936.6
Wed, 3:00 PM PDT35Good338.4
Wed, 4:00 PM PDT37Good2.440.4
Wed, 5:00 PM PDT39Good2.542.3
Wed, 6:00 PM PDT40Good243.7
Wed, 7:00 PM PDT41Good1.944.5
Wed, 8:00 PM PDT41Good244.5
Wed, 9:00 PM PDT41Good2.144.2
Wed, 10:00 PM PDT40Good1.843.6
Wed, 11:00 PM PDT39Good1.542.5
Thu, 12:00 AM PDT38Good1.741.4
Thu, 1:00 AM PDT37Good2.140.2
Thu, 2:00 AM PDT35Good2.438.5
Thu, 3:00 AM PDT33Good336.8
Thu, 4:00 AM PDT32Good3.135.4
Thu, 5:00 AM PDT31Good3.434.4
Thu, 6:00 AM PDT31Good333.5
Thu, 7:00 AM PDT30Good3.332.7
Thu, 8:00 AM PDT29Good3.631.8
Thu, 9:00 AM PDT28Good430.9
Thu, 10:00 AM PDT28Good4.530.8
Thu, 11:00 AM PDT29Good531.2
Thu, 12:00 PM PDT30Good4.332.1
Thu, 1:00 PM PDT31Good3.633.2
Thu, 2:00 PM PDT31Good2.934.6
Thu, 3:00 PM PDT33Good2.536.3
Thu, 4:00 PM PDT35Good1.938.3
Thu, 5:00 PM PDT37Good2.340.6
Thu, 6:00 PM PDT39Good2.642.8
Thu, 7:00 PM PDT41Good3.444.4
Thu, 8:00 PM PDT42Good3.845.7
Thu, 9:00 PM PDT43Good4.546.9
Thu, 10:00 PM PDT44Good4.748
Thu, 11:00 PM PDT45Good549.1
Fri, 12:00 AM PDT45Good4.949.8
Fri, 1:00 AM PDT45Good5.549.8
Fri, 2:00 AM PDT45Good649.5
Fri, 3:00 AM PDT44Good6.848.6
Fri, 4:00 AM PDT44Good6.847.1
Fri, 5:00 AM PDT42Good6.745.1
Fri, 6:00 AM PDT39Good6.542.6
Fri, 7:00 AM PDT37Good6.839.7
Fri, 8:00 AM PDT38Good7.437
Fri, 9:00 AM PDT38Good6.735.1
Fri, 10:00 AM PDT31Good4.233.2
Fri, 11:00 AM PDT29Good331.7
Fri, 12:00 PM PDT28Good231
Fri, 1:00 PM PDT28Good1.730.6
Fri, 2:00 PM PDT28Good1.130.6
Fri, 3:00 PM PDT28Good1.230.9
Fri, 4:00 PM PDT29Good131.3
Fri, 5:00 PM PDT29Good1.131.4
Fri, 6:00 PM PDT29Good0.931.9
Fri, 7:00 PM PDT30Good0.832.7
Fri, 8:00 PM PDT31Good0.333.4
Fri, 9:00 PM PDT31Good0.133.8
Fri, 10:00 PM PDT31Good034
Fri, 11:00 PM PDT31Good0.433.7
Sat, 12:00 AM PDT31Good0.433.1
Sat, 1:00 AM PDT30Good0.432.2
Sat, 2:00 AM PDT28Good0.230.9
Sat, 3:00 AM PDT27Good0.229.4
Sat, 4:00 AM PDT25Good0.327.9
Sat, 5:00 AM PDT24Good0.326.5

Fine particles in micrograms per cubic meter, ozone in parts per billion as an 8-hour average. The index for each hour is EPA’s: the ozone figure is already the 8-hour average the ozone index is defined on, and the particle figure is run through EPA’s NowCast, which is how an hourly PM2.5 concentration becomes an index.

Smoke

NOAA’s analysts have not drawn smoke over Washoe County in satellite imagery today.

NOAA’s model forecasts near-surface smoke peaking at 3.1 µg/m³ around Thu, 9:00 AM PDT.

Smoke on the radar over Washoe County

What this means

Good

Air quality is satisfactory, and air pollution poses little or no risk.

Who is affected
Nobody is expected to be affected.
What to do
It is a good day to be outside.
Index range
0 to 50

Category descriptions are the Environmental Protection Agency’s own.

What these numbers are. An index beside a monitor’s name is a measurement, published hourly by AirNow and preliminary until the operating agency certifies it. A category for today or tomorrow is a state or local agency forecaster’s own forecast for a reporting area. An hourly index is NOAA’s air quality model on a five-kilometer grid, not a reading from any instrument. Where a town has no monitor within reach, only the model figures appear, and the page says so.

Nearby

The nearest towns with a page of their own, closest first.

Weather forecast for Washoe CountyWarnings in Washoe CountyLive radar over Washoe CountyNevada air quality

Sources

Observations and daily forecasts from AirNow, the US Environmental Protection Agency’s program with NOAA, the National Park Service, NASA, tribal, state and local agencies. Hourly forecasts from NOAA’s National Air Quality Forecast Capability. Smoke analysis from NOAA’s Hazard Mapping System. Alerts from the National Weather Service. Index categories and breakpoints are EPA’s, as revised in 2024.