By Paul Yeager, author of Weather Whys: Facts, Myths, and Oddities
The Great Pumpkin hasn’t even come and gone yet, but winter storm watches are in effect for portions of eastern Pennsylvania and northwestern New Jersey for Saturday and Saturday evening.
Significant snow by winter standards is a threat from West Virginia and Maryland northeastward into much of southern New England, including the potential for more than eight inches from northeastern Pennsylvania to interior southern New England.
If this Eastern snow storm does materialize–and that’s not certain yet due to model uncertainty and the depth of the cold air so early in the season–it would fall in a region where many trees still have their leaves, resulting in widespread tree damage and downed power lines. This would be more of a concern than the traditional travel problems since the snow would melt fairly quickly on paved surfaces after being plowed or treated with salt.
The downed trees and power lines could be a major problem.
Let’s just hope that it’s more computer model mayhem than a legitimate fall snow storm, but the computer models are frightening–and not in a Halloween sort of way.
Here are images from the 18z run of the GFS, meaning the mid-afternoon run of the main American computer forecast model for those of you who don’t speak meteorology-ese.
This map is the model output for midday on Saturday:
Here is the map for six hours later, at roughly 1 a.m. on Sunday.



