A thick blanket of 'radiation fog' has descended upon the southeastern United States, creating perilous conditions for morning commuters and prompting official warnings for up to five million residents.
Widespread Advisories and Travel Hazards
The National Weather Service (NWS) has activated a dense fog advisory across 78 counties in Georgia, South Carolina, and Florida this Friday morning. The primary danger is severely reduced visibility, with drivers unable to see more than a quarter of a mile ahead. Major urban centres grappling with the impenetrable mist include Augusta and Macon in Georgia, as well as Columbia and Charleston in South Carolina. The fog is also affecting parts of the northern Florida Panhandle.
"If driving, slow down, use your headlights, and leave plenty of distance ahead of you," NWS officials urged in their public warning. Most land-based advisories are expected to remain until at least 10am ET, with some coastal and marine alerts, including for waters off Georgia and South Carolina, extending to 1pm Friday afternoon.
Understanding Radiation Fog and Health Concerns
Despite its alarming name, this type of fog has no connection to nuclear radiation. It forms under specific meteorological conditions: recent rains or high humidity leave excess moisture in the air, and overnight, under clear skies with light winds, the ground cools rapidly. This cooling process releases heat, saturating the air near the surface and creating the characteristic dense, low-lying fog.
However, officials have noted that such dense, low-level fog can act as a lid, trapping local pollutants close to the ground. This means that before the sun burns the fog off later in the day, particles from factory emissions and vehicle exhausts can linger over populated areas. This degraded air quality can exacerbate respiratory conditions like asthma.
Public Reports and Regional Impact
Some residents have taken to social media to report unusual characteristics of the fog this week. One individual on X described it as "thick and smelly," while another in northeast Georgia claimed, "it's not normal fog, it smells like burning plastic and leaves a residue on our car windows." The latter user publicly appealed to Health Secretary Robert F Kennedy Jr to investigate the "suspicious particles" within the Georgian fog.
Satellite imagery from the National Oceanic and Atmospheric Administration (NOAA) confirmed the extensive fog bank covering the Southeast early Friday, with patches visible over Alabama, Mississippi, North Carolina, and Tennessee. While no fog alerts were issued for those states, the NWS did signal flood watches for Alabama, Mississippi, and Tennessee due to a moist airmass and slow-moving weather boundary, forecasting potential rainfall exceeding five inches by Saturday.
Radiation fog is a common phenomenon in the southeastern US, particularly during the fall and winter months when longer nights facilitate greater cooling. The combination of cooler temperatures and abundant moisture from seasonal storms creates ideal conditions for this disruptive, and at times hazardous, weather event.
