Delaware air quality

Greenwood, Delaware Air Quality

Sussex County38.807, -75.591

The nearest monitor to Greenwood, at SEAFORD, 11 miles away, measured an index of 34 at Sat, 5:00 AM EDT, which is Good for ground-level ozone. Delaware Dept. of Natural Resources and Environment forecasts Good for Sussex County today and Good tomorrow.

Measured now
34 · Good
Today
32 · Good
Tomorrow
30 · Good
Pollutant
Ozone

Fine particles on the map

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

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

Now

Good

Nearest monitor
SEAFORD, 11 miles away (site 100051002)
Index measured
34 · Good
Measured at
Sat, 5:00 AM EDT
Fine particles
3.6 µg/m³
Ozone
37 ppb
Reporting area
Sussex County, DE, 14 miles away
Reported by
Delaware Dept. of Natural Resources and Environment
Area index
38 · Good

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

Today and tomorrow

Delaware Dept. of Natural Resources and Environment's own forecast for Sussex County, written by a forecaster rather than read off a model.

DayCategoryIndexPollutant
TodayGood32Ozone
TomorrowGood30Ozone
Monday, September 28Good33Ozone

The forecaster’s discussion

Written by Delaware Dept. of Natural Resources and Environment for Sussex County and filed with AirNow.

Saturday, September 26 and Sunday, September 27: As a low-pressure system gradually strengthens and advances northward off the Mid-Atlantic coast, moderate and gusty northerly to northwesterly winds will disperse pollutants and transport clean air into Delaware each day. In addition, clouds and rain showers will hinder ozone development. As a result, AQI levels are anticipated to be Good for ozone and PM2.5 on both days. Monday, northerly to northwesterly winds will weaken slightly, limiting dispersion. However, clouds and rain showers early in the day will continue to inhibit ozone production, and pollutant carryover from the weekend will be low. Thus, AQI levels are anticipated to remain Good for ozone and PM2.5.

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 33, Good, around Sun, 8:00 PM EDT, from the run issued Fri, 11:00 PM EDT. This is a model, not a measurement.

HourIndexCategoryPM2.5Ozone
Sat, 6:00 AM EDT26Good1.328.7
Sat, 7:00 AM EDT27Good129.6
Sat, 8:00 AM EDT28Good1.230.2
Sat, 9:00 AM EDT28Good1.530.6
Sat, 10:00 AM EDT28Good1.830.5
Sat, 11:00 AM EDT28Good2.230.5
Sat, 12:00 PM EDT28Good2.530.3
Sat, 1:00 PM EDT27Good3.129.7
Sat, 2:00 PM EDT27Good3.329.1
Sat, 3:00 PM EDT26Good3.428.5
Sat, 4:00 PM EDT26Good3.528.1
Sat, 5:00 PM EDT25Good3.427.7
Sat, 6:00 PM EDT25Good427.3
Sat, 7:00 PM EDT25Good427
Sat, 8:00 PM EDT24Good3.726.9
Sat, 9:00 PM EDT24Good3.126.7
Sat, 10:00 PM EDT24Good3.126.5
Sat, 11:00 PM EDT24Good2.926.3
Sun, 12:00 AM EDT24Good326.3
Sun, 1:00 AM EDT24Good3.126.1
Sun, 2:00 AM EDT23Good3.125.9
Sun, 3:00 AM EDT23Good2.425.9
Sun, 4:00 AM EDT24Good2.426
Sun, 5:00 AM EDT24Good226.2
Sun, 6:00 AM EDT24Good1.826.4
Sun, 7:00 AM EDT24Good1.826.2
Sun, 8:00 AM EDT23Good225.9
Sun, 9:00 AM EDT24Good226
Sun, 10:00 AM EDT24Good2.126.3
Sun, 11:00 AM EDT24Good2.326.3
Sun, 12:00 PM EDT24Good2.626.3
Sun, 1:00 PM EDT24Good326.4
Sun, 2:00 PM EDT24Good3.526.5
Sun, 3:00 PM EDT24Good4.226.7
Sun, 4:00 PM EDT24Good4.826.6
Sun, 5:00 PM EDT26Good5.226.2
Sun, 6:00 PM EDT29Good5.926
Sun, 7:00 PM EDT31Good6.125.7
Sun, 8:00 PM EDT33Good6.225.5
Sun, 9:00 PM EDT33Good6.225
Sun, 10:00 PM EDT33Good624.9
Sun, 11:00 PM EDT32Good5.524.9
Mon, 12:00 AM EDT30Good5.225.3
Mon, 1:00 AM EDT29Good4.825.8
Mon, 2:00 AM EDT28Good4.426
Mon, 3:00 AM EDT26Good4.226.1
Mon, 4:00 AM EDT24Good3.926
Mon, 5:00 AM EDT24Good3.626.2
Mon, 6:00 AM EDT24Good3.626.1
Mon, 7:00 AM EDT23Good3.425.9
Mon, 8:00 AM EDT23Good3.325.4

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 Greenwood 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 Greenwood

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 GreenwoodWarnings in Sussex CountyLive radar over GreenwoodDelaware 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.