The famous postal creed, "Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds" does not, apparently, apply to polar vortex conditions. The United States Postal Service said Tuesday it will not deliver mail to areas some parts of the country on Wednesday due to the extreme cold brought on by the polar vortex.

Service will be suspended Wednesday in parts of Minnesota, Michigan, Indiana, Illinois (including parts of Chicago), Wisconsin, Ohio, Iowa, western Pennsylvania, the Dakotas and Nebraska, the USPS said.

In addition to deliveries, pickups from businesses, residences and collection boxes are also suspended.

Get Breaking News Delivered to Your Inbox

People across the country are preparing for the record-shattering temperatures -- many schools, businesses and government services are closed and hundreds of flights have been delayed or cancelled. Chicago is expected to be colder than the base camp at Mount Everest, with temperatures expected to plunge to 21 below zero. Experts are warning about hypothermia and frostbite.

There have been at least six polar vortex-related deaths in Illinois, Iowa, Indiana, Wisconsin and Minnesota.