Frost Advisory issued April 19 at 3:21AM CDT until April 19 at 9:00AM CDT by NWS

...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM CDT THIS MORNING... * WHAT...Temperatures as low as 30 will result in frost formation. * WHERE...In Missouri, Saint Charles MO, Saint Louis City MO and Saint Louis MO Counties. In Illinois, Madison IL and Saint Clair Counties. * WHEN...Until 9 AM CDT this morning.