Dense Fog in Illinois, April 29, 2013

Name: Dense Fog in Illinois, April 29, 2013
Start: 2013-04-29T01:00
End: 2013-04-29T07:00
Location: Illinois

April 29, 2013 · NWS PAH · 19 events in 19 counties and zones

Areas of dense fog formed due to the combination of clearing skies and light winds near a surface high over the Tennessee Valley. Due to recent rains, there was plenty of moisture at ground level.

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
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Fire, smoke and dust
Marine and coastal
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Open the live radar over this ground

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.

Areas of dense fog formed due to the combination of clearing skies and light winds near a surface high over the Tennessee Valley. Due to recent rains, there was plenty of moisture at ground level. Visibility was occasionally one-quarter mile or less across southern Illinois.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Paducah, KY wrote its last area forecast discussion before the first event at Apr 28, 10:49 PM CST, 2 hours 11 minutes earlier.

Area forecast discussion, Apr 28, 10:49 PM CST, 2 hours 11 minutes before

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Hazardous weather outlook, Apr 28, 2:19 PM CST, 10 hours 41 minutes before

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In the hours before

Special weather statement, Apr 28, 7:59 PM CST, 5 hours 1 minute before

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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

19 dense fog. Local standard time, as filed.

Dense Fog, Alexander

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Alexander forecast zone
Reported by: AWOS
Coordinates: 37.192, -89.338 (the zone’s center; the record gives no point)

Dense Fog, Edwards

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Edwards forecast zone
Reported by: AWOS
Coordinates: 38.417, -88.053 (the zone’s center; the record gives no point)

Dense Fog, Franklin

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Franklin forecast zone
Reported by: AWOS
Coordinates: 37.992, -88.924 (the zone’s center; the record gives no point)

Dense Fog, Gallatin

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Gallatin forecast zone
Reported by: AWOS
Coordinates: 37.763, -88.230 (the zone’s center; the record gives no point)

Dense Fog, Hamilton

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Hamilton forecast zone
Reported by: AWOS
Coordinates: 38.082, -88.539 (the zone’s center; the record gives no point)

Dense Fog, Hardin

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Hardin forecast zone
Reported by: AWOS
Coordinates: 37.518, -88.267 (the zone’s center; the record gives no point)

Dense Fog, Jackson

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Jackson forecast zone
Reported by: AWOS
Coordinates: 37.785, -89.382 (the zone’s center; the record gives no point)

Dense Fog, Jefferson

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Jefferson forecast zone
Reported by: AWOS
Coordinates: 38.301, -88.924 (the zone’s center; the record gives no point)

Dense Fog, Johnson

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Johnson forecast zone
Reported by: AWOS
Coordinates: 37.460, -88.881 (the zone’s center; the record gives no point)

Dense Fog, Massac

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Massac forecast zone
Reported by: AWOS
Coordinates: 37.219, -88.708 (the zone’s center; the record gives no point)

Dense Fog, Perry

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Perry forecast zone
Reported by: AWOS
Coordinates: 38.084, -89.367 (the zone’s center; the record gives no point)

Dense Fog, Pope

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Pope forecast zone
Reported by: AWOS
Coordinates: 37.413, -88.562 (the zone’s center; the record gives no point)

Dense Fog, Pulaski

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Pulaski forecast zone
Reported by: AWOS
Coordinates: 37.223, -89.127 (the zone’s center; the record gives no point)

Dense Fog, Saline

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Saline forecast zone
Reported by: AWOS
Coordinates: 37.753, -88.541 (the zone’s center; the record gives no point)

Dense Fog, Union

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Union forecast zone
Reported by: AWOS
Coordinates: 37.471, -89.255 (the zone’s center; the record gives no point)

Dense Fog, Wabash

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Wabash forecast zone
Reported by: AWOS
Coordinates: 38.446, -87.844 (the zone’s center; the record gives no point)

Dense Fog, Wayne

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Wayne forecast zone
Reported by: AWOS
Coordinates: 38.430, -88.426 (the zone’s center; the record gives no point)

Dense Fog, White

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: White forecast zone
Reported by: AWOS
Coordinates: 38.088, -88.180 (the zone’s center; the record gives no point)

Dense Fog, Williamson

When: April 29, 1:00 AM CST to 7:00 AM CST
Where: Williamson forecast zone
Reported by: AWOS
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

Every storm in Illinois in 2013 Every state in 2013 This day in weather history Warnings in Illinois, April 2013

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: 441815, 441816, 441817, 441818, 441819, 441820, 441821, 441822, 441823, 441824, 441826, 441827, 441828, 441829, 441830, 441832, 441833, 441834, 441835.