CHICAGO -- In retrospect, an alarm did sound that death was on the way.
The alert came from Iowa, where oven-like air was powerful enough to fell tens of thousands of cattle, turkeys, chickens and hogs.
"That," says Gary McCray, a physician specializing in geriatric care, "should have been the tip-off." The brutal heat was headed for Chicago.
It arrived July 12 and stayed for five days, including two consecutive days of triple-digit temperatures. At one point the thermometer at Midway Airport read 106 degrees.
Even so, no one figured that the summer of 1995 would claim the lives of more than 450 people in Cook County, most of them elderly, many poor, most living alone.
No one expected fatalities on the scale of an airliner crash or the great fire that leveled the city in 1871.
"The city got blindsided," said one staffer at the Chicago Department of Aging. "We weren't ready."
Why the tally of the dead rose so astonishingly high -- causing a traffic jam of hearses at the morgue for days -- is a question with many answers. It has left the city divided between those who believe the tragedy was an unavoidable act of nature and those who say it could -- and should -- have been prevented.
The search for scapegoats is well under way.
The Illinois Commerce Commission is investigating Commonwealth Edison, the utility that lighted Wrigley Field for a Cubs night game while neighboring streets lost electricity.
Republicans in the state Senate have called for an investigation of Democratic Mayor Richard M. Daley's handling of the crisis. The Centers for Disease Control and Prevention will study the medical examiner's criteria for ruling that a death was linked to heat.
Mayor Daley is appointing a committee to investigate just about everything it can.
A lawyer has already filed the first class-action suit, against CommEd.
The circumstances, they all will find, are complicated.
The combination of heat, humidity -- which makes perspiring less effective -- and a sky without cloud cover was unprecedented here. The center of the scorching air mass responsible for the misery across the Midwest and East Coast stalled directly over Chicago and Milwaukee, 81 miles north, which experienced a proportionally similar death rate.
When the heat persisted, "the red light should go on," said Dr. McCray. "Every degree above 98.6 [body temperature] is much more critical than every degree below it."
Chicago's homes and high-rises are designed with the region's bone-chilling winters in mind, with minimal cross-ventilation in order to retain heat. Fear of crime also kept many windows locked tight.
To some people, it seemed there was little that could have been done to thwart nature's course.
"This is an act of God, a disaster akin to a hurricane or flood," said Cook County Medical Examiner Edmund R. Donoghue at a news conference Thursday. "I don't think any human being is responsible for this."
Still, the first public warnings lacked urgency. The National Weather Service sent out an advisory July 11: Don't overexert yourself, drink liquids. The Department of Aging handed out its "Stay cool" brochure with hot-weather tips, as it had since June.
City government did not fully mobilize until hundreds had died, temperatures were falling and the crisis had become a matter more of politics than of public health.
Then there is the nature of the populace: tough, independent. Perhaps ornery is not too strong a word.
Take Walter Waiter, 81, who told neighbors that he'd get through the heat just fine.
His body was discovered July 14 in his superheated beige brick house.
All his windows were closed; many were painted shut. He had long scorned air conditioners as "too high-tech," his downstairs tenant, Fred Gunther, recalled.
Chicago is not the first city to suffer through such a heat disaster. Kansas City and St. Louis, with much smaller populations than Chicago, recorded 133 and 113 deaths respectively in July 1980. Philadelphia reported 118 deaths in 1993.
Those cities now have heat plans.
Kansas City and St. Louis issue heat alerts. As the emergency heightens, air-conditioned public buildings, charities and churches open their doors to the afflicted and at-risk.
Philadelphia works with a University of Delaware climatologist, who warns municipal leaders when killer heat is headed that way. Then the city sets up a hot line and a buddy system for senior citizens.
There is no definitive proof that the plans work. But this year, with about 700 heat deaths around the country, Philadelphia reported 18; St. Louis, 17; and Kansas City, nine.
Now Chicago is following their lead. The mayor announced a revised heat plan Thursday that mirrors the St. Louis-Kansas City model.