Washington air quality

Clyde Hill, Washington Air Quality

King County47.632, -122.218

The nearest monitor to Clyde Hill, at Bellevue-SE 12th, 4 miles away, measured an index of 41 at Sun, 4:00 AM PDT, which is Good for fine particles (PM2.5). Puget Sound Clean Air Agency forecasts Good for Seattle-Bellevue-Kent Valley today and Good tomorrow.

Measured now
41 · Good
Today
39 · Good
Tomorrow
39 · Good
Pollutant
PM2.5

Radar

Reflectivity now over Clyde Hill, Washington. Open it to see the particulate forecast on the map.

Open the live radar with the particulate forecast

Radar mosaic and map layers from NOAA MRMS and 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 Clyde Hill right now. All Washington warnings.

Now

Good

Nearest monitor
Bellevue-SE 12th, 4 miles away (site 530330031)
Index measured
41 · Good
Measured at
Sun, 4:00 AM PDT
Fine particles
6.8 µg/m³
Reporting area
Seattle-Bellevue-Kent Valley, WA, 7 miles away
Reported by
Puget Sound Clean Air Agency
Area index
62 · Moderate

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

Today and tomorrow

Puget Sound Clean Air Agency's own forecast for Seattle-Bellevue-Kent Valley, written by a forecaster rather than read off a model.

DayCategoryIndexPollutant
TodayGood39PM2.5
TomorrowGood39PM2.5
Tuesday, September 22Good39PM2.5
Wednesday, September 23Good39PM2.5

The forecaster’s discussion

Written by Puget Sound Clean Air Agency for Seattle-Bellevue-Kent Valley and filed with AirNow.

For Sep 18-21 (Fri-Mon): Expect GOOD air quality this weekend.

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 71, Moderate, around Sun, 1:00 AM PDT, from the run issued Sat, 11:00 PM PDT. This is a model, not a measurement.

HourIndexCategoryPM2.5Ozone
Sun, 1:00 AM PDT71Moderate19.3
Sun, 2:00 AM PDT70Moderate17.9
Sun, 3:00 AM PDT69Moderate17.4
Sun, 4:00 AM PDT66Moderate15.3
Sun, 5:00 AM PDT63Moderate13.4
Sun, 6:00 AM PDT61Moderate12.8
Sun, 7:00 AM PDT58Moderate11.514.1
Sun, 8:00 AM PDT55Moderate10.213
Sun, 9:00 AM PDT54Moderate10.212.6
Sun, 10:00 AM PDT55Moderate12.112.3
Sun, 11:00 AM PDT55Moderate11.413.3
Sun, 12:00 PM PDT54Moderate10.515
Sun, 1:00 PM PDT54Moderate10.117.2
Sun, 2:00 PM PDT53Moderate9.519
Sun, 3:00 PM PDT52Moderate9.221.8
Sun, 4:00 PM PDT52Moderate8.824.5
Sun, 5:00 PM PDT49Good826.7
Sun, 6:00 PM PDT48Good829
Sun, 7:00 PM PDT51Moderate10.429.8
Sun, 8:00 PM PDT53Moderate12.629.6
Sun, 9:00 PM PDT57Moderate1428.6
Sun, 10:00 PM PDT58Moderate13.427.4
Sun, 11:00 PM PDT56Moderate11.325.5
Mon, 12:00 AM PDT54Moderate8.823.3
Mon, 1:00 AM PDT51Moderate7.520.8
Mon, 2:00 AM PDT42Good6.217.8
Mon, 3:00 AM PDT37Good5.715.7
Mon, 4:00 AM PDT33Good5.613.9
Mon, 5:00 AM PDT33Good5.912.6
Mon, 6:00 AM PDT29Good4.811.3
Mon, 7:00 AM PDT32Good6.110
Mon, 8:00 AM PDT40Good8.78.8
Mon, 9:00 AM PDT54Moderate13.98.3
Mon, 10:00 AM PDT63Moderate20.98.5
Mon, 11:00 AM PDT71Moderate23.69
Mon, 12:00 PM PDT71Moderate20.510
Mon, 1:00 PM PDT65Moderate13.411.4
Mon, 2:00 PM PDT60Moderate11.613.5
Mon, 3:00 PM PDT57Moderate10.216.4
Mon, 4:00 PM PDT53Moderate8.619.8
Mon, 5:00 PM PDT48Good722.6
Mon, 6:00 PM PDT39Good5.625.2
Mon, 7:00 PM PDT44Good926.5
Mon, 8:00 PM PDT52Moderate11.926.8
Mon, 9:00 PM PDT55Moderate12.826.3
Mon, 10:00 PM PDT54Moderate10.624.9
Mon, 11:00 PM PDT52Moderate8.622.7
Tue, 12:00 AM PDT51Moderate920.6
Tue, 1:00 AM PDT52Moderate10.318.3
Tue, 2:00 AM PDT52Moderate9.215.1
Tue, 3:00 AM PDT48Good8.112.6
Tue, 4:00 AM PDT41Good611.1
Tue, 5:00 AM PDT30Good3.69.5
Tue, 6:00 AM PDT24Good3.28.7
Tue, 7:00 AM PDT20Good37.5
Tue, 8:00 AM PDT19Good3.36.5
Tue, 9:00 AM PDT17Good2.56.7
Tue, 10:00 AM PDT16Good2.88.2
Tue, 11:00 AM PDT18Good3.510.5
Tue, 12:00 PM PDT19Good3.812.2
Tue, 1:00 PM PDT21Good414.3
Tue, 2:00 PM PDT19Good3.116
Tue, 3:00 PM PDT18Good3.418.5
Tue, 4:00 PM PDT19Good3.420.6
Tue, 5:00 PM PDT20Good3.822
Tue, 6:00 PM PDT21Good3.823.6
Tue, 7:00 PM PDT28Good6.423.7
Tue, 8:00 PM PDT33Good7.123.2
Tue, 9:00 PM PDT44Good9.922.4
Tue, 10:00 PM PDT51Moderate10.621.4
Tue, 11:00 PM PDT53Moderate1119.9

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 Clyde Hill in satellite imagery today.

NOAA’s model forecasts no measurable smoke near the ground here over the next two days.

Smoke on the radar over Clyde Hill

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 Clyde HillWarnings in King CountyLive radar over Clyde HillWashington 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.