Dense Fog, Alexander
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Alexander forecast zone
- Coordinates
- 37.192, -89.338 (the zone’s center; the record gives no point)
Dense Fog in Illinois, December 18, 1997
Patchy dense fog reduced visibility to near zero in some spots. With temperatures in the mid 20s, a layer of frost formed, even on some roads.
Where it happened
Every event with a place to put it; 19 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
- 0
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 19
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 PAH wrote it up.
Patchy dense fog reduced visibility to near zero in some spots. With temperatures in the mid 20s, a layer of frost formed, even on some roads. This resulted in slick spots for early morning commuters.
The radar
The national radar mosaic for the moment the first event began.
Event by event
19 dense fog. Local standard time, as filed.
Dense Fog, Edwards
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Edwards forecast zone
- Coordinates
- 38.417, -88.053 (the zone’s center; the record gives no point)
Dense Fog, Franklin
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Franklin forecast zone
- Coordinates
- 37.992, -88.924 (the zone’s center; the record gives no point)
Dense Fog, Gallatin
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Gallatin forecast zone
- Coordinates
- 37.763, -88.230 (the zone’s center; the record gives no point)
Dense Fog, Hamilton
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Hamilton forecast zone
- Coordinates
- 38.082, -88.539 (the zone’s center; the record gives no point)
Dense Fog, Hardin
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Hardin forecast zone
- Coordinates
- 37.518, -88.267 (the zone’s center; the record gives no point)
Dense Fog, Jackson
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Jackson forecast zone
- Coordinates
- 37.785, -89.382 (the zone’s center; the record gives no point)
Dense Fog, Jefferson
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Jefferson forecast zone
- Coordinates
- 38.301, -88.924 (the zone’s center; the record gives no point)
Dense Fog, Johnson
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Johnson forecast zone
- Coordinates
- 37.460, -88.881 (the zone’s center; the record gives no point)
Dense Fog, Massac
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Massac forecast zone
- Coordinates
- 37.219, -88.708 (the zone’s center; the record gives no point)
Dense Fog, Perry
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Perry forecast zone
- Coordinates
- 38.084, -89.367 (the zone’s center; the record gives no point)
Dense Fog, Pope
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Pope forecast zone
- Coordinates
- 37.413, -88.562 (the zone’s center; the record gives no point)
Dense Fog, Pulaski
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Pulaski forecast zone
- Coordinates
- 37.223, -89.127 (the zone’s center; the record gives no point)
Dense Fog, Saline
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Saline forecast zone
- Coordinates
- 37.753, -88.541 (the zone’s center; the record gives no point)
Dense Fog, Union
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Union forecast zone
- Coordinates
- 37.471, -89.255 (the zone’s center; the record gives no point)
Dense Fog, Wabash
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Wabash forecast zone
- Coordinates
- 38.446, -87.844 (the zone’s center; the record gives no point)
Dense Fog, Wayne
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Wayne forecast zone
- Coordinates
- 38.430, -88.426 (the zone’s center; the record gives no point)
Dense Fog, White
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- White forecast zone
- Coordinates
- 38.088, -88.180 (the zone’s center; the record gives no point)
Dense Fog, Williamson
- When
- December 18, 5:30 AM CST to 9:00 AM CST
- Where
- Williamson forecast zone
- Coordinates
- 37.730, -88.930 (the zone’s center; the record gives no point)
What these are
- Dense Fog
- Fog reducing visibility to a quarter mile or less, filed where it caused accidents or disruption.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Flood in Florida, December 18 to 31, 1997
- Dense Fog in Kentucky, December 18, 1997
- Dense Fog in Missouri, December 18, 1997
- Dense Fog in Indiana, December 18, 1997
- High Wind in Alaska, December 18 to 19, 1997
- High Wind in Alaska, December 18, 1997
- Heavy Snow in Wyoming, December 18 to 19, 1997
- High Wind in Alaska, December 18, 1997
- Heavy Snow in Nevada, December 18, 1997
More
Every storm in Illinois in 1997Every state in 1997This day in weather historyWarnings in Illinois, December 1997
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 2026-09-24. Each event’s entry at NCEI: 5625891, 5625892, 5625893, 5625894, 5625895, 5625896, 5625897, 5625898, 5625899, 5625900, 5625901, 5625902, 5625903, 5625904, 5625905, 5625906, 5625907, 5625908, 5625909.