MINNEAPOLIS (WCCO) — The United States Postal Services says “neither snow nor rain nor heat” keeps them from delivering.

But extreme cold does.

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USPS announced Tuesday afternoon they are suspending mail deliveries Wednesday in Minnesota, western Wisconsin, Iowa and western Illinois. Pickups from businesses, residences and collection boxes are also suspended.

Carriers like Dave Mayou in Duluth will have the day off. He typically walks about seven miles each work day, no matter the weather.

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All of Minnesota will have feel-like temperatures Wednesday morning ranging between minus-32 and minus-56 degrees. Frostbite can set in on exposed skin within five minutes of exposure.