Well both. The fires and the atmospheric conditions. Apparently the smoke was high up in the column over the upper midwest. Then some atmospheric condition along the east coast caused it to sink back down the column.
And you can picture where that low pressure system sits from that second map. That's why the smoke was circling around and not thru those New England cities.
Regards.
Yeah.
That’s why I posted this.
It happened before in 1966 and 1953 and 1963.
It may have been more industrial pollution that served as the haze then.
We need to counter the hysteria and especially the narrative that this means we can’t use gas or gasoline.