California air quality

Rocklin, California Air Quality

Placer County38.791, -121.236

The nearest monitor to Rocklin, at Roseville - N.Sunrise/Douglas, 3 miles away, measured an index of 36 at Mon, 5:00 AM PDT, which is Good for fine particles (PM2.5). Placer County APCD forecasts Moderate for Roseville-Rocklin today and Moderate tomorrow.

Measured now
36 · Good
Today
61 · Moderate
Tomorrow
67 · Moderate
Pollutant
PM2.5

Fine particles on the map

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

Now

Good

Nearest monitor
Roseville - N.Sunrise/Douglas, 3 miles away (site 060610006)
Index measured
36 · Good
Measured at
Mon, 5:00 AM PDT
Fine particles
6.8 µg/m³
Reporting area
Roseville-Rocklin, CA, 2 miles away
Reported by
Placer County APCD
Area index
36 · Good

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

Today and tomorrow

Placer County APCD's own forecast for Roseville-Rocklin, written by a forecaster rather than read off a model.

DayCategoryIndexPollutant
TodayModerate61Ozone
TomorrowModerate67Ozone
Wednesday, September 23Moderate77Ozone
Thursday, September 24Moderate87Ozone
Friday, September 25Moderate67Ozone

The forecaster’s discussion

Written by Placer County APCD for Roseville-Rocklin and filed with AirNow.

Sunday, increasing clouds and slightly cooler temperatures will hinder ozone production as a trough of low pressure aloft approaches central California. Therefore, ozone levels will be high-Good. Monday, mostly sunny skies and temperatures warming into the mid-80s will enhance ozone formation in the Sacramento region. However, light to moderate onshore winds will develop through the afternoon, dispersing pollutants and leading to low-Moderate ozone levels. Tuesday, lighter winds will allow pollutants to accumulate in the Sacramento region. Furthermore, mostly sunny skies with warm temperatures will continue to aid ozone production, yielding mid-Moderate ozone levels.

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 66, Moderate, around Wed, 10:00 PM PDT, from the run issued Sun, 11:00 PM PDT. This is a model, not a measurement.

HourIndexCategoryPM2.5Ozone
Mon, 1:00 AM PDT51Moderate8.7
Mon, 2:00 AM PDT46Good7.2
Mon, 3:00 AM PDT46Good8
Mon, 4:00 AM PDT40Good6
Mon, 5:00 AM PDT37Good6.1
Mon, 6:00 AM PDT36Good6.3
Mon, 7:00 AM PDT39Good823.2
Mon, 8:00 AM PDT38Good6.622.4
Mon, 9:00 AM PDT36Good6.122.2
Mon, 10:00 AM PDT39Good7.922.5
Mon, 11:00 AM PDT43Good8.823.3
Mon, 12:00 PM PDT46Good9.324.7
Mon, 1:00 PM PDT49Good9.926.9
Mon, 2:00 PM PDT53Moderate11.529.9
Mon, 3:00 PM PDT55Moderate12.533.6
Mon, 4:00 PM PDT55Moderate11.338
Mon, 5:00 PM PDT55Moderate10.742
Mon, 6:00 PM PDT55Moderate1145.5
Mon, 7:00 PM PDT53Moderate9.147.6
Mon, 8:00 PM PDT47Good7.148
Mon, 9:00 PM PDT43Good6.347
Mon, 10:00 PM PDT41Good7.244.8
Mon, 11:00 PM PDT41Good7.642.1
Tue, 12:00 AM PDT43Good8.238.7
Tue, 1:00 AM PDT44Good8.334.9
Tue, 2:00 AM PDT42Good7.231.3
Tue, 3:00 AM PDT43Good828.4
Tue, 4:00 AM PDT38Good5.826.5
Tue, 5:00 AM PDT33Good525.3
Tue, 6:00 AM PDT31Good5.124.2
Tue, 7:00 AM PDT33Good6.322.9
Tue, 8:00 AM PDT33Good5.921.7
Tue, 9:00 AM PDT33Good621.2
Tue, 10:00 AM PDT36Good7.321.2
Tue, 11:00 AM PDT38Good7.521.7
Tue, 12:00 PM PDT38Good722.8
Tue, 1:00 PM PDT37Good6.224.4
Tue, 2:00 PM PDT38Good7.426.9
Tue, 3:00 PM PDT42Good8.530.2
Tue, 4:00 PM PDT46Good9.134.4
Tue, 5:00 PM PDT51Moderate10.438.6
Tue, 6:00 PM PDT54Moderate11.743.1
Tue, 7:00 PM PDT56Moderate13.447
Tue, 8:00 PM PDT60Moderate16.149
Tue, 9:00 PM PDT62Moderate16.149.1
Tue, 10:00 PM PDT63Moderate16.448
Tue, 11:00 PM PDT62Moderate14.546
Wed, 12:00 AM PDT60Moderate13.143.2
Wed, 1:00 AM PDT57Moderate10.939.9
Wed, 2:00 AM PDT54Moderate8.935.8
Wed, 3:00 AM PDT53Moderate9.531.8
Wed, 4:00 AM PDT51Moderate8.429
Wed, 5:00 AM PDT48Good8.127.4
Wed, 6:00 AM PDT48Good8.925.9
Wed, 7:00 AM PDT51Moderate9.624.1
Wed, 8:00 AM PDT51Moderate9.322.1
Wed, 9:00 AM PDT52Moderate9.821.2
Wed, 10:00 AM PDT52Moderate10.221.4
Wed, 11:00 AM PDT53Moderate11.423
Wed, 12:00 PM PDT53Moderate10.225.5
Wed, 1:00 PM PDT52Moderate8.728.7
Wed, 2:00 PM PDT51Moderate8.232.8
Wed, 3:00 PM PDT49Good837.9
Wed, 4:00 PM PDT47Good7.743.3
Wed, 5:00 PM PDT47Good8.448.1
Wed, 6:00 PM PDT49Good9.852.1
Wed, 7:00 PM PDT51Moderate9.754.6
Wed, 8:00 PM PDT56Moderate14.455.1
Wed, 9:00 PM PDT61Moderate17.554.4
Wed, 10:00 PM PDT66Moderate19.352.9
Wed, 11:00 PM PDT66Moderate17.851

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 Rocklin in satellite imagery today.

NOAA’s model forecasts near-surface smoke peaking at 1.3 µg/m³ around Tue, 6:00 PM PDT.

Smoke on the radar over Rocklin

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 RocklinWarnings in Placer CountyLive radar over RocklinCalifornia 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.