…FROST ADVISORY IN EFFECT FROM 1 AM TO 8 AM CDT FRIDAY… WHAT…Temperatures in the low to mid 30s will result in frost formation. WHERE…Much of central Iowa. Mainly north of a Creston to Knoxville and Grinnell line. WHEN…From 1 AM to 8 AM CDT Friday. IMPACTS…Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS… Take steps now to protect tender plants from the cold.