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During July 2002, dozens of forest fires raged across northern Quebec sending a thick smoky
haze southward as far as Washington, DC and prompting health advisories in Quebec, New York,
New Jersey and Pennsylvania. This smoke pall brought reminders of a May 1780 event: New
England's infamous "Dark Day." Hi, I'm Bryan Yeaton for The Weather Notebook.
For days, the New England sun had taken on an unusual reddish hue within a dirty yellow sky.
At mid-morning May 19th, a blanket of darkness descended across New England. Birds sang their
evening songs, then went silent. As darkness intensified, cows were said to have walked back
to their barns, thinking it was evening.
Noon was nearly as dark as night, making outdoor travel difficult. New Haven's Connecticut
Journal reported the darkness was as deep as when candles were lit in the evening.
Samuel Williams of Bradford, Connecticut, commented, "In some places, the darkness was so
great, that persons could not see to read common print in the open air.... The extent of this
darkness was very remarkable."
Many feared divine wrath. Yale president Timothy Dwight wrote, "It was the general opinion
that the day of judgment was at hand." Church attendance immediately picked up.
The cause of the darkness was not divine, but natural. Today, we can attribute the darkness to
smoke and ash concentrated into a dense blanket which blocked the sunlight. Forest fires
burning to the west in Canada or northern New England most likely spawned the dense smoke
cloud which was drawn across New England by passing low pressure. This is supported by reports
from Boston that the air smelled like a "malt-house or coal-kiln," and a something resembling
ashes settled on pools of rain water.
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