California air quality

Plymouth, California Air Quality

Amador County38.482, -120.845

The nearest monitor to Plymouth, at Jackson - Clinton, 11 miles away, measured an index of 28 at Sat, 10:00 AM PDT, which is Good for ground-level ozone. El Dorado County AQMD forecasts Good for Placerville today and Good tomorrow.

Measured now
28 · Good
Today
38 · Good
Tomorrow
35 · Good
Pollutant
Ozone

Fine particles on the map

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

Forecast fine particulate matter from NOAA’s National Air Quality Forecast Capability over Plymouth, California 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 Plymouth right now. All California warnings.

Now

Good

Nearest monitor
Jackson - Clinton, 11 miles away (site 060050002)
Index measured
28 · Good
Measured at
Sat, 10:00 AM PDT
Ozone
35 ppb
Reporting area
Placerville, CA, 17 miles away
Reported by
El Dorado County AQMD
Area index
28 · Good

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

Today and tomorrow

El Dorado County AQMD's own forecast for Placerville, written by a forecaster rather than read off a model.

DayCategoryIndexPollutant
TodayGood38Ozone
TomorrowGood35Ozone
Monday, September 28Good39Ozone
Tuesday, September 29Good44Ozone
Wednesday, September 30Good47Ozone
Thursday, October 1Good49Ozone

The forecaster’s discussion

Written by El Dorado County AQMD for Placerville and filed with AirNow.

Saturday through Monday, a trough of low pressure aloft will gradually move across the Sacramento Valley, promoting atmospheric mixing. Furthermore, mild temperatures will inhibit ozone production, and day to day pollutant carryover will be low. Therefore, ozone levels will be Good on all three days.

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 44, Good, around Mon, 7:00 PM PDT, from the run issued Sat, 5:00 AM PDT. This is a model, not a measurement.

HourIndexCategoryPM2.5Ozone
Sat, 11:00 AM PDT12Good2.1
Sat, 12:00 PM PDT12Good2.2
Sat, 1:00 PM PDT23Good2.625.9
Sat, 2:00 PM PDT26Good2.628.9
Sat, 3:00 PM PDT30Good2.832.1
Sat, 4:00 PM PDT32Good235.6
Sat, 5:00 PM PDT35Good2.638.5
Sat, 6:00 PM PDT36Good2.739.9
Sat, 7:00 PM PDT37Good2.640.7
Sat, 8:00 PM PDT37Good2.740.5
Sat, 9:00 PM PDT36Good3.139.8
Sat, 10:00 PM PDT35Good3.238.8
Sat, 11:00 PM PDT34Good2.937.1
Sun, 12:00 AM PDT31Good3.634.8
Sun, 1:00 AM PDT30Good3.632.5
Sun, 2:00 AM PDT28Good4.730.5
Sun, 3:00 AM PDT26Good5.128.6
Sun, 4:00 AM PDT25Good4.127.3
Sun, 5:00 AM PDT24Good426.2
Sun, 6:00 AM PDT23Good3.725.2
Sun, 7:00 AM PDT22Good424.5
Sun, 8:00 AM PDT22Good3.923.8
Sun, 9:00 AM PDT22Good423.1
Sun, 10:00 AM PDT21Good3.423.2
Sun, 11:00 AM PDT22Good4.123.8
Sun, 12:00 PM PDT23Good4.724.6
Sun, 1:00 PM PDT24Good526
Sun, 2:00 PM PDT27Good5.527.9
Sun, 3:00 PM PDT28Good4.730.7
Sun, 4:00 PM PDT31Good3.734
Sun, 5:00 PM PDT34Good3.837.6
Sun, 6:00 PM PDT37Good4.540.5
Sun, 7:00 PM PDT39Good4.942.6
Sun, 8:00 PM PDT40Good5.243.6
Sun, 9:00 PM PDT40Good5.743.8
Sun, 10:00 PM PDT39Good5.442.6
Sun, 11:00 PM PDT37Good4.840.3
Mon, 12:00 AM PDT34Good4.437.1
Mon, 1:00 AM PDT31Good4.233.3
Mon, 2:00 AM PDT27Good4.729.6
Mon, 3:00 AM PDT25Good4.526.2
Mon, 4:00 AM PDT24Good423.9
Mon, 5:00 AM PDT24Good422
Mon, 6:00 AM PDT19Good320.8
Mon, 7:00 AM PDT18Good2.919.8
Mon, 8:00 AM PDT18Good2.919.2
Mon, 9:00 AM PDT20Good4.219.1
Mon, 10:00 AM PDT22Good4.620.1
Mon, 11:00 AM PDT22Good4.221.6
Mon, 12:00 PM PDT22Good4.123.4
Mon, 1:00 PM PDT23Good4.225.8
Mon, 2:00 PM PDT27Good5.728.8
Mon, 3:00 PM PDT31Good6.433.1
Mon, 4:00 PM PDT34Good5.337.9
Mon, 5:00 PM PDT39Good5.242.4
Mon, 6:00 PM PDT42Good4.545.4
Mon, 7:00 PM PDT44Good3.647.7
Mon, 8:00 PM PDT44Good2.848
Mon, 9:00 PM PDT43Good3.246.9
Mon, 10:00 PM PDT41Good3.144.6
Mon, 11:00 PM PDT38Good2.441.3
Tue, 12:00 AM PDT34Good2.637.4
Tue, 1:00 AM PDT31Good1.733.5
Tue, 2:00 AM PDT28Good2.330.2
Tue, 3:00 AM PDT25Good1.627.1
Tue, 4:00 AM PDT23Good0.525.5
Tue, 5:00 AM PDT22Good0.824.2

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 Plymouth in satellite imagery today.

NOAA’s model forecasts near-surface smoke peaking at 0.5 µg/m³ around Sun, 8:00 AM PDT.

Smoke on the radar over Plymouth

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 PlymouthWarnings in Amador CountyLive radar over PlymouthCalifornia 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.