It's a Fourpeat Fivepeat for Chicago: Over 80° for 4th 5th Consecutive Day

March 18, 7 PM CDT Update: It's yet another early spring record crushed at Chicago, as the high of 81° made it the 5th consecutive day of 80°+ temperatures. The previous high of 74°, originally set in 1903, had only been tied before in 1918 and 1969, but it was surpassed by 7°.

The graph above, from the National Weather Service, shows how far beyond the previous warmest Marches this month has been to date.

5 PM CDT Update: The high temperature was 82° at Chicago, smashing the old record for March 17 of 74° originally set in 1894 and tied in 2009. Rockford also hit 82°, easily beating the old record of 75° in 2009.

The National Weather Service reports that this breaks a century-plus record by over a month for the earliest string of 4 consecutive days with 80° temperatures or higher:

CHICAGO SET A NEW RECORD FOR MOST NUMBER OF 80 DEGREE DAYS IN A  
MARCH WITH 4.  
  
MARCH 17 WAS THE 4TH CONSECUTIVE DAY ABOVE 80...WHICH BROKE THE   
PREVIOUS RECORD FOR EARLIEST IN THE SEASON TO HAVE 4 CONSECUTIVE 80   
DEGREE DAYS. PREVIOUSLY THE EARLIEST CHICAGO HAS EVER SEEN 4   
CONSECUTIVE 80 DEGREE DAYS WAS BACK ON APRIL 15-18 1896.   

Original post:
After hitting 80° or higher for a record-breaking 3 consecutive days, Chicago has reached that temperature again this afternoon. For the last 2 hours, the temperature has been at least 81°. The regional weather map (click to enlarge) for 3 pm CDT from the College of DuPage shows 80° or higher temperatures throughout most of central and northern Illinois, southern Wisconsin, and Iowa.