There will be several nights this week where temperatures will fall below zero, but two of those nights, Tuesday night into Wednesday morning and Thursday night into Friday morning will see readings well below zero. The image above shows the forecasted morning lows for Friday morning (which will be the coldest of the next week) via the GFS 12z model run this morning. It shows the entire state of Iowa will be well below zero that morning with some locations in northern Iowa and southern Minnesota seeing readings in the -20s. Along with the colder valley locations, this may be possible, given another snow storm is expected right before this time period with another fresh blanket of snow. A slow warming trend will commence at that time and the weekend will see readings heading back toward average.