73°F in Dallas, 56°F in Chicago, same day. Photo: Don Scarborough, CC BY-SA.
The 30-year NWS average high for October 31. Not this year's forecast.
The Halloween Blizzard. Still the benchmark for a ruined Halloween.
The Halloween nor'easter. Records broke in more than 20 cities that year.
Wetter South, milder North, per NOAA. A trend, not a guarantee. See the full guide.
City-by-city averages, real history, and the honest limits of a 3-week forecast.