Lamar County, Mississippi Air Quality

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.

• Air Quality Alert Air Quality Alert issued September 21 at 4:48PM CDT by NWS Memphis TNCrittenden; DeSoto; Shelby
  Full text

  AQAMEG The Shelby County Health Department has issued a Code Orange Ozone Health Advisory effective for Shelby County Tennessee, Crittenden County Arkansas, and DeSoto County Mississippi, including the city of Memphis that will remain in effect until sunset. This ozone health advisory is due to monitored ozone values that are unhealthy for sensitive groups. These values have exceeded the Environmental Protection Agency's federal safe health standard. The Shelby County Health Department recommends that sensitive groups which include active children and adults, and people with respiratory disease, such as asthma, limit prolonged outdoor exertion. Please continue to check the latest air quality forecasts and updates until monitored values return to safe levels. For more information go to www.airnow.gov.

All Mississippi warnings

Moderate

Nearest monitor

Hattiesburg, 15 miles away (site 280350004)

Index measured

55 · Moderate

Measured at

Mon, 5:00 PM CDT

Fine particles

11.4 µg/m³

Reporting area

Hattiesburg, MS, 15 miles away

Reported by

Mississippi DEQ

Area index

55 · Moderate

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

No state or local agency has filed a daily forecast for this area. NOAA’s model forecast below covers the same hours.

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 57, Moderate, around Mon, 9:00 PM CDT, from the run issued Mon, 7:00 AM CDT. This is a model, not a measurement.

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.

NOAA’s Hazard Mapping System analysts drew medium smoke over Lamar County in satellite imagery today (Mon, 10:00 AM CDT to Mon, 12:00 PM CDT). That is smoke seen from above; it is not always smoke at ground level.

NOAA’s model forecasts near-surface smoke peaking at 1.2 µg/m³ around Mon, 6:00 PM CDT.

Smoke on the radar over Lamar County

Moderate

Air quality is acceptable. There may be a risk for some people, particularly those who are unusually sensitive to air pollution.

Who is affected

People who are unusually sensitive to ozone or fine particles.

What to do

If you are unusually sensitive, consider making long or intense outdoor activity shorter or easier.

Index range

51 to 100

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.

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

• Purvis, MS7 miles
• West Hattiesburg, MS11 miles
• Arnold Line, MS12 miles
• Lumberton, MS15 miles
• Rawls Springs, MS15 miles
• Sumrall, MS15 miles
• Hattiesburg, MS15 miles
• Glendale, MS16 miles

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.