Dense Fog in Illinois, September 23, 2025

Name: Dense Fog in Illinois, September 23, 2025
Start: 2025-09-23T00:30
End: 2025-09-23T07:30
Location: Illinois

September 23, 2025 · NWS PAH · 10 events in 10 counties and zones

Clear skies and calm winds following recent rainfall led to dense fog development, mainly along the Interstate 64 corridor through southern Illinois.

Where it happened

Every event with a place to put it; 10 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

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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: 10

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.

Clear skies and calm winds following recent rainfall led to dense fog development, mainly along the Interstate 64 corridor through 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 Sep 22, 9:57 PM CST, 2 hours 33 minutes earlier.

Area forecast discussion, Sep 22, 9:57 PM CST, 2 hours 33 minutes before

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Hazardous weather outlook, Sep 22, 12:57 PM CST, 11 hours 33 minutes 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

10 dense fog. Local standard time, as filed.

Dense Fog, Wayne

When: September 23, 12:30 AM CST to 6:30 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, Wabash

When: September 23, 12:30 AM CST to 7:30 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, Edwards

When: September 23, 1:00 AM CST to 7:30 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, White

When: September 23, 2:00 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, Hamilton

When: September 23, 2:30 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, Gallatin

When: September 23, 3:00 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, Hardin

When: September 23, 3:00 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, Jefferson

When: September 23, 5:30 AM CST to 6:30 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, Perry

When: September 23, 5:30 AM CST to 7:30 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, Franklin

When: September 23, 5:30 AM CST to 7:30 AM CST
Where: Franklin forecast zone
Reported by: AWOS
Coordinates: 37.992, -88.924 (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 2025 Every state in 2025 This day in weather history Warnings in Illinois, September 2025

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 2026-09-30. Each event’s entry at NCEI: 1292180, 1292183, 1292181, 1292187, 1292186, 1292188, 1292199, 1292179, 1292184, 1292185.