Heat, Cook
- When
- July 28, 11:00 AM CST to July 31, 7:00 AM CST
- Where
- Cook forecast zone
- Deaths
- 93 direct, 0 indirect
- Reported by
- GOVT OFFICIAL
Heat in Illinois, July 28 to 31, 1999
An intense heat wave began in the Chicago metropolitan area July 28th and continued through the morning of July 31st. High temperatures on the 28th were in the lower to middle 90s with heat indices 100 to 105.
Where it happened
Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
- Tornadoes
- Tropical storms and surge
- Floods
- Wind
- Hail
- Winter weather
- Heat and drought
- Cold
- Fire, smoke and dust
- Marine and coastal
- Other
The toll
- Deaths
- 99
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 7
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
What happened
The episode as NWS LOT wrote it up.
An intense heat wave began in the Chicago metropolitan area July 28th and continued through the morning of July 31st. High temperatures on the 28th were in the lower to middle 90s with heat indices 100 to 105. On the 29th the temperatures soared to the middle and upper 90s with heat indices 110 to 120. The heat peaked on the 30th with high temperatures over 100 and heat indices around 115 to 120. Chicago set an all-time dew point record of 82 at Midway airport on the morning of the 30th. The minimum heat index in downtown Chicago was 100. Of the 99 fatalities, 93 were in Cook County, 3 were in Will County and 3 were in Lake County.
The radar
The national radar mosaic for the moment the first event began.
Event by event
7 heat. Local standard time, as filed.
Heat, Du Page
- When
- July 28, 11:00 AM CST to July 31, 7:00 AM CST
- Where
- Du Page forecast zone
- Reported by
- GOVT OFFICIAL
- Coordinates
- 41.852, -88.086 (the zone’s center; the record gives no point)
Heat, Kane
- When
- July 28, 11:00 AM CST to July 31, 7:00 AM CST
- Where
- Kane forecast zone
- Reported by
- GOVT OFFICIAL
- Coordinates
- 41.939, -88.429 (the zone’s center; the record gives no point)
Heat, Kendall
- When
- July 28, 11:00 AM CST to July 31, 7:00 AM CST
- Where
- Kendall forecast zone
- Reported by
- GOVT OFFICIAL
- Coordinates
- 41.591, -88.429 (the zone’s center; the record gives no point)
Heat, Lake
- When
- July 28, 11:00 AM CST to July 31, 7:00 AM CST
- Where
- Lake forecast zone
- Deaths
- 3 direct, 0 indirect
- Reported by
- GOVT OFFICIAL
- Coordinates
- 42.349, -87.862 (the zone’s center; the record gives no point)
Heat, McHenry
- When
- July 28, 11:00 AM CST to July 31, 7:00 AM CST
- Where
- McHenry forecast zone
- Reported by
- GOVT OFFICIAL
- Coordinates
- 42.324, -88.452 (the zone’s center; the record gives no point)
Heat, Will
- When
- July 28, 11:00 AM CST to July 31, 7:00 AM CST
- Where
- Will forecast zone
- Deaths
- 3 direct, 0 indirect
- Reported by
- GOVT OFFICIAL
The people who died
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Heat, Cook | 1999-08-01 | 42 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 85 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 60 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 81 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 67 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 72 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 52 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-03 | 79 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 55 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 60 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 47 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 51 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 57 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 56 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 80 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 56 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-03 | 77 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-04 | 86 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-04 | 41 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-04 | 79 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-04 | 51 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-04 | 59 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-05 | 60 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-06 | 77 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-08 | 40 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 60 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 70 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 48 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 85 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 57 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 86 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 59 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 70 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 87 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 72 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 77 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 82 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 72 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 84 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 88 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 92 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 92 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 82 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 73 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 54 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 72 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 64 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 70 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 41 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 82 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 89 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 71 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 57 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 46 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 51 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 42 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 80 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 64 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 82 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 80 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 65 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 48 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 75 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 81 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 87 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 76 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 49 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 80 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 64 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 70 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 50 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 77 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 63 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 68 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 81 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 72 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 72 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 53 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 73 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 71 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 84 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 49 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 68 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 81 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-01 | 86 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-02 | 79 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-08-04 | 70 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-08-06 | 51 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 52 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 46 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-30 | 86 | Female | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 75 | Male | Permanent Home | Direct |
| Heat, Cook | 1999-07-31 | 88 | Female | Permanent Home | Direct |
| Heat, Lake | 1999-08-02 | 71 | Female | Permanent Home | Direct |
| Heat, Lake | 1999-07-30 | 90 | Male | Permanent Home | Direct |
| Heat, Lake | 1999-07-30 | 30 | Female | Permanent Home | Direct |
| Heat, Will | 1999-08-01 | 82 | Male | Permanent Home | Direct |
| Heat, Will | 1999-07-30 | 66 | Male | Permanent Home | Direct |
| Heat, Will | 1999-07-31 | 66 | Female | Permanent Home | Direct |
What these are
- Heat
- Heat below excessive heat criteria that still caused deaths, injuries or significant impacts.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Tornadoes and Flash Flood in Ohio, July 28, 1999
- Heat in Illinois, July 28 to 31, 1999
- Damaging Winds in Virginia, July 28, 1999
- Heat in Wisconsin, July 28 to 30, 1999
- Heat in Minnesota, July 28 to 30, 1999
- Heat in Nebraska, July 28 to 29, 1999
- Heat in Arkansas, July 28, 1999
- Flash Flooding and Hail in Pennsylvania, July 28, 1999
- Tornado and Hail in Michigan, July 28, 1999
- Heat in Iowa, July 28 to 29, 1999
- Flash Flood and Damaging Wind in Arizona, July 28, 1999
- Flash Flood in Colorado, July 28, 1999
More
Every storm in Illinois in 1999Every state in 1999This day in weather historyWarnings in Illinois, July 1999
Sources
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 5710162, 5710163, 5710164, 5710165, 5710166, 5710167, 5710168.