Since Saturday, a forest fire has been raging in Burlington County, which has thrown up a plume of smoke so large people in Bergen and Hudson counties -- as much as 80 miles away from the seat of the fire -- reported smelling burning.
The huge fire also forced the closure of Rt. 72 in Barnegat.
Residents living in a long swath of the state stretching from Burlington County up to Newark and farther northeast experienced the nation's worst air quality Sunday morning, according to the National Weather Service.
On the Air Quality Index scale, eastern and northern New Jersey reached 164, a number deemed "Unhealthy." Unhealthy air is still not the worst level of air quality, however -- the next highest level is "Very Unhealthy," and the worst level is "Hazardous."
Jonathan O'Brien, a meteorologist with the National Weather Service in Mount Holly, said the poor air in parts of the state was due to the fire and an inversion overnight that trapped particle-filled air closer to the surface.
But he said a cold front and rain system expected to pass through the region Sunday will dramatically improve air quality.
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