AN UNSEASONABLY STRONG AND COOL AREA OF HIGH PRESSURE WILL SPREAD
ACROSS THE MID AND UPPER MISSISSIPPI VALLEY OVERNIGHT. THE
COMBINATION OF CLEAR SKIES AND DECREASING WINDS ASSOCIATED WITH
THE HIGH WILL ALLOW TEMPERATURES TO DROP INTO THE MIDDLE TO
UPPER 30S ACROSS PORTIONS OF NORTHERN ILLINOIS OVERNIGHT. SOME
PATCHY FROST IS POSSIBLE IN SOME OF THE COLDER MORE SHELTERED
LOCATIONS BY SUNRISE...ESPECIALLY IN LOW LYING AREAS. ALTHOUGH
WIDESPREAD FROST IS NOT EXPECTED...ANY FROST THAT DOES FORM COULD
RESULT IN DAMAGE TO SENSITIVE VEGETATION IF LEFT UNPROTECTED.
TEMPERATURES WILL QUICKLY WARM AFTER SUNRISE...ENDING THE THREAT
