How weather affects what you tip the delivery guy

grub hub tipping

Would you give someone a better tip for delivering your food in a blizzard?

Food orders increase when bad weather hits -- as do tips, according to online food delivery company GrubHub. But severe winter weather can push tips up even higher.

This year, tips in New York City increased 9% during the Jan. 26 snow storm compared to the city's year-round average. In Boston, tips rose 6% during the Feb. 2 blizzard and gratuity jumped 12% in Chicago during the Feb. 1 storm.

Related: Could this mean the end of tipping?

Even extreme cold is enough to make some customers more generous.

"If the temperature drops significantly, or there's something out of the ordinary, we see a high correlation with tip percentages and temperatures," said Allie Mack, a spokeswoman for GrubHub.

For example, during the 2013-2014 winter season, the company said the average tip was 14.1%, only a slight increase from the 13.9% average over the rest of the year. But during the Polar Vortex in January 2014, average tips jumped in some colder cities. Tips were more than 15% higher than average in Detroit and Minneapolis on certain days of the month.

The tips are analyzed as a percentage of the overall order, and cash tips can't be tracked. At the end of ordering process, GrubHub customers can select to add a 10%, 15% or 20% tip or add their own amount.

For the entire 2013-2014 winter, the highest tipping cities were: Denver at 15.7% of the total delivery price, Dallas at 15.1% and Charlottesville, Virginia, at 15%.

Early deliveries also tend to get higher tips. Tipping percentages increased 7.3% from the daily average from 6-9 in the morning in the winter season. "Perhaps people are being more generous because they aren't ordering as much," Mack said.

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