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WEDNESDAY OCTOBER 25 - INDIAN SUMMER, PART 1
The term "Indian Summer" refers to a period of above-average temperatures
in mid or late autumn, with mainly sunny days and cool nights. Around here,
a bona-fide Indian Summer usually has to follow at least one killing frost.
Given how variable our weather can be, and the wide range of time when Indian
Summer can occur, it's really not that unusual for there to be an "Indian Summer"
in the Delaware Valley. In fact, some years might have 2 or 3 "Indian Summers."
An example of a weather pattern that brings us Indian summer weather goes
something like this: a sprawling area of high pressure sits just off the East
Coast. This high brought chilly air days before when it moved out of Canada.
But as the high settles along the East Coast, our winds locally start to blow
from the south and southwest. This brings a warm-up which sometimes lasts a
few days. And this scenario can play out several times before the winter chill
sets in for good.