National Weather Service Weather Forecast Office

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PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE CHICAGO IL
734 PM CDT THU SEP 13 2012 /834 PM EDT THU SEP 13 2012/

...SIGNIFICANT 24-HOUR TEMPERATURE CHANGE...

A STRONG COLD FRONT MOVED THROUGH THE REGION LATE WEDNESDAY NIGHT
INTO THURSDAY MORNING...WITH THE COLDER SURGE FOLLOWING INTO
THURSDAY AFTERNOON. ACCOMPANYING THE COOLER NORTHWEST FLOW WAS ALSO
RAIN WHICH FURTHER USHERED TEMPERATURES DOWNWARD. COMPARED TO THE
WARM AIR AHEAD OF THE FRONT EXPERIENCED ON WEDNESDAY...THERE
WERE LARGE 24-HOUR TEMPERATURE CHANGES OBSERVED. THIS WAS ESPECIALLY
TRUE ACROSS NORTH CENTRAL ILLINOIS AND PARTS OF NORTHEAST
ILLINOIS...WHERE THE COLDER AIR MOVED IN THE EARLIEST.

LOCATION              TEMPERATURE    HOUR     24-HOUR TEMP CHANGE
--------------------------------------------------------------------
AURORA                    55         5 PM             -29
CHICAGO EXECUTIVE APRT    56         5 PM             -30
CHICAGO MIDWAY APRT       62         5 PM             -24
CHICAGO OHARE APRT        56         6 PM             -28
DEKALB                    54         4 PM             -33
DUPAGE AIRPORT            55         5 PM             -30
PERU                      55         4 PM             -30
ROCHELLE                  55         3 PM             -33
ROCKFORD                  54         4 PM             -35
STERLING                  54         3 PM             -36
WAUKEGAN                  54         4 PM             -32

THE AFTERNOON TEMPERATURES IN THE MID 50S WERE THE COLDEST AT BOTH
CHICAGO AND ROCKFORD SINCE MAY 31ST.

$$

MTF/CM