All the forecasts were predicted temperatures heading well below zero Sunday night, but many parts of West Michigan awoke to sub-zero temps on Sunday morning, with Kalamazoo leading the way at 5 degrees below zero. (Two cities north of Grand Rapids, Fremont and Big Rapids also matched Kalamazoo's five degree below zero temperature.)

The early arrival of sub zero temperatures has caused the National Weather Service to revise the low for Sunday night into Monday, down to -9 below zero, with wind chills near -20 below zero. The Wind Chill Advisory is from 6pm Sunday night to Noon on Monday, January 21st.

A Wind Chill Advisory means that cold air and the wind will
combine to create low wind chills. Frostbite and hypothermia can
occur if precautions are not taken. Make sure you wear a hat and
gloves...Frost bite will be possible in under 30 minutes of
exposure at these readings. - National Weather Service, Grand Rapids