I think this will be the last freeze warning of the season given the lows tonight and the date on which it’s occurring.
This freeze warning will be in effect from Midnight Tuesday through 9am Tuesday morning for the following counties in Iowa, Benton, Linn, Jones, Jackson, Iowa, Johnson, Cedar, Clinton, Muscatine, Scott, Keokuk, Washington, Louisa, Jefferson, Henry, Des Moines, Van Buren and Lee. Temperatures will fall well into the 20s with a few upper teens in the colder locations thus fully killing anything that isn’t covered.