A dramatic pattern shift is bringing the chilliest air since spring to millions of people in the central and eastern United States, making areas that have struggled so far to shed lingering warmth feel more like November than October.

Columbus and much of Ohio is under a freeze warning in effect from 2 a.m. to 9 a.m. Thursday as temperatures are predicted to dip as low as 30 degrees, according to the National Weather Service in Wilmington.