Early next week has the potential to bring some of the warmest air of the season. With high pressure in the eastern part of the country and an area of low pressure passing through the Dakotas, strong warm air advection will bring Gulf air northward.
On the left you will see a map of 850mb temps for next Monday of the latest 18z GFS model run. It is showing widespread 10-15C temps, which translates to 60s/70s for at least the southern half of the Midwest, depending on where the front sets up. Stay tuned for updates on this incoming Spring.