Dense Fog in Wisconsin, February 24 to 25, 2001

Name: Dense Fog in Wisconsin, February 24 to 25, 2001
Start: 2001-02-24T19:00
End: 2001-02-25T02:00
Location: Wisconsin

February 24 to 25, 2001 · NWS MKX · 3 events in 3 counties and zones

Moist southeast winds and recent snow melt combined to develop dense fog across south-central Wisconsin. Visibilities were reduced to 1/8 to 1/4 mile, resulting in about a dozen vehicle accidents.

Where it happened

Every event with a place to put it; 3 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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Wind
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Fire, smoke and dust
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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: 3

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 MKX wrote it up.

Moist southeast winds and recent snow melt combined to develop dense fog across south-central Wisconsin. Visibilities were reduced to 1/8 to 1/4 mile, resulting in about a dozen vehicle accidents. On the weather map, a warm front was moving north through northern 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 Milwaukee, WI wrote its last area forecast discussion before the first event at Feb 24, 6:54 PM CST, 6 minutes earlier.

Area forecast discussion, Feb 24, 6:54 PM CST, 6 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

3 dense fog. Local standard time, as filed.

Dense Fog, Iowa

When: February 24, 7:00 PM CST to February 25, 2:00 AM CST
Where: Iowa forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.001, -90.135 (the zone’s center; the record gives no point)

Dense Fog, Lafayette

When: February 24, 7:00 PM CST to February 25, 2:00 AM CST
Where: Lafayette forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 42.661, -90.132 (the zone’s center; the record gives no point)

Dense Fog, Green

When: February 24, 7:00 PM CST to February 25, 2:00 AM CST
Where: Green forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 42.680, -89.602 (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 Wisconsin in 2001 Every state in 2001 This day in weather history Warnings in Wisconsin, February 2001

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: 5232337, 5232338, 5232339.