May 20th Chill in Perspective

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE CHICAGO IL
907 PM CDT WED MAY 20 2015

...PUTTING THE CHILL OF WEDNESDAY INTO PERSPECTIVE...

WEDNESDAY MAY 20TH BROUGHT TEMPERATURES TO NORTHERN
ILLINOIS...NORTHWEST INDIANA...AND ADJACENT AREAS THAT WERE MORE
SEASONAL FOR EARLY SPRING THAN LATE SPRING. HERE ARE SOME FACTS
FOR THE LONGER TERM CLIMATE SITES OF ROCKFORD AND CHICAGO:

---ROCKFORD---

- THE HIGH OF 47 BROKE A RECORD FOR MAY 20TH. THE PREVIOUS HAD
  BEEN 51 SET IN 2002.

- THIS WAS THE COLDEST HIGH ANYTIME IN THE MONTH OF MAY SINCE 47
  WAS OBSERVED FOR A HIGH ON MAY 3 2011.

- THIS WAS ONLY THE 6TH TIME SINCE 1906 THAT THE TEMPERATURE AT
  ROCKFORD REMAINED BELOW 50 DEGREES THIS LATE INTO SPRING. HERE
  ARE THE ONLY SUB 50-DEGREE HIGHS ON RECORD FOR MAY 20TH OR
  LATER INTO EARLY SUMMER ON RECORD:

RANK    HIGH     DATE
------------------------
 1.      46    5/28/1906
 2.      47    5/20/2015
         47    5/28/1984
         47    5/28/1965
         47    5/23/1917
 6.      48    5/24/1992


---CHICAGO---

- BECAUSE OF THE REGULAR INFLUENCE OF LAKE MICHIGAN FOR CHICAGO
  IN THE SPRINGTIME...THE HIGH OF 48 WAS NOT A RECORD FOR THE DAY.

- THE HIGH OF 48 WAS THE 10TH TIME SINCE 2000 THAT THE HIGH IN
  MAY WAS 48 DEGREES OR COLDER.

- LAST MAY ACTUALLY SAW A COLDER HIGH...WITH 46 DEGREES ON MAY 16
  2014. SNOW WAS ACTUALLY OBSERVED IN PARTS OF NORTHERN ILLINOIS
  THAT DAY.

- THIS WAS ONLY THE 7TH DAY SINCE THE OFFICIAL OBSERVATION SITE
  MOVED AWAY FROM VERY NEAR TO LAKE MICHIGAN /1942/ THAT A HIGH
  TEMPERATURE REMAINED BELOW 50 DEGREES THIS LATE INTO SPRING.
  HERE IS A LIST OF THOSE SEVEN DATES FROM MAY 20TH OR LATER:

RANK    HIGH     DATE
------------------------
 1.      46    5/24/1992
 2.      48    5/20/2015
         48    5/20/2002
         48    5/26/1961
         48     6/1/1946
         48     6/3/1945
 7.      49    5/26/2011

$$

MTF/MOTT/IZZI

RECORD EVENT REPORT 
NATIONAL WEATHER SERVICE CHICAGO IL
502 PM CDT WED MAY 20 2015

...RECORD LOW MAXIMUM TEMPERATURE SET AT ROCKFORD IL...

 A RECORD LOW MAXIMUM TEMPERATURE OF 47 OCCURRED AT ROCKFORD IL 
TODAY. THIS WILL BREAK THE PREVIOUS LOW MAXIMUM TEMPERATURE OF 51 
SET IN 2002.

Rockford also reported ice pellets, which is officilally logged as frozen precipitation. That had not been reported on the celandar day of May 20th before in Rockford's period of record (since 1906).

RECORD EVENT REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
457 PM CDT WED MAY 20 2015

...RECORD SNOWFALL SET AT ROCKFORD IL...

 A RECORD SNOWFALL OF A TRACE WAS SET AT ROCKFORD IL TODAY. THIS
IS THE FIRST TIME ON THIS DATE.


$$