CHICAGO — Unseasonably cool weather will arrive next week in the Midwest and as far south as Arkansas and Oklahoma.

It is not, however, the second coming of a polar vortex, a phrase the National Weather Service’s Chicago office tweeted earlier this week to describe the upcoming sweater weather. The office quickly learned that wasn’t such a good idea, said Amy Seeley, a weather service meteorologist who spent a good chunk of Friday morning fielding a flood of telephone calls from the media.

“I think people are pretty sensitive to those words,” she said.