Below is a map of the actual track of the low pressure system Wednesday through Thursday. The small 2 digit numbers next the "L" is the pressure in millibars with the "9" missing. So, "82" would be 982 mb, which was the lowest pressure in the storm when it was crossing the Chicago area. The storm deepened 1 millibar per hour for 15 hours. Storms that strengthen 1 mb per hour or more for at least 24 hours are considered "explosive cyclogenesis", a technical term for rapidly deepening storms that are relatively rare. So, although this storm did not meet the criteria, it came rather close. The times are in UTC or Zulu, so 18z along the CO/KS border is Noon Wed, 00z over Kansas was 6 pm Wed, etc.
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The snow and blowing likely caused some road closures in rural areas. Northwest winds gusted to 40 to 50 mph during the afternoon and early evening hours of Thursday. These strong winds, along with falling and/or blowing snow, resulted in blizzard or near blizzard conditions in open and exposed areas, with visibilities reduced to one quarter mile or less.