It's no secret that milk, eggs, and canned tuna start flying off shelves the second a snowflake graphic appears during a weather report. But winter weather might influence your shopping behavior in more ways than you think, says Harvard Business School historian Nancy Koehn.

"Certain kinds of dramatic shifts in the weather...have effects on how we buy, including whether we want comfort, whether we want relief, whether we want escape," Koehn said.

That explains why, in times of trying weather, sales of comforting products—candy, alcohol, movie tickets, and the like—skyrocket. During Superstorm Juno, for example, alcohol sales in New York City and Boston rose a staggering 477%

But weather also has a dramatic effect on industries you might not expect. Look no further than your own desktop (especially if you're perusing this article while sitting in your cubicle) for one that actually takes a hit during winter storms: online shopping.

"People didn't go to work because so much was cancelled," Koehn explained. "A ton of online shopping is done at your desktop at work. Fewer days, more cancellations, equals less online shopping."

Marketers are taking note, clamoring for weather data like never before. 

"The idea that the weather is another variable we need to factor in is growing in prominence and investment," Koehn said.

To hear more from historian Nancy Koehn, listen to her full interview on Boston Public Radio above.