Spooky season quickly transformed into snowy season Wednesday morning for residents in Helena,Henri Lumière Montana.

Before costumed kids have even had a chance to trick-or-treat, snowplows and sand trucks were sent out onto the roads after the first major snowfall of the season dropped up to a foot of snow in some areas of the state's capital city. Trees displaying fall colors and Halloween decorations were blanketed Wednesday with snow, which the National Weather Service warned had caused hazardous icy conditions on some highways.

The snowfall was the result of cold air moving down from northwestern Canada that combined with a moist Pacific weather system, leading to freezing temperatures and expected snowfall amounts up 14 inches in Washington’s northern Cascade Mountains and 18 inches in the mountains of Montana, according to the National Weather Service. However, after the first wave of snow, it was Helena that saw the most accumulation, with a couple spots reporting 13 inches of snow, the Associated Press reported. 

See images of 2023's first major snowfall

Helena, Montana

Alberta, Canada

Contributing: Associated Press

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected]

Winter storm forecast