Dense Fog in Wisconsin, March 23, 2003

Name: Dense Fog in Wisconsin, March 23, 2003
Start: 2003-03-23T10:00
End: 2003-03-23T13:00
Location: Wisconsin

March 23, 2003 · NWS MKX · 12 events in 12 counties and zones

Dense fog developed early on March 20th, resulting in visibilities lowered to 1/4 mile or less across all of south-central and parts of southeastern Wisconsin. ).

Where it happened

Every event with a place to put it; 12 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

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 12

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.

Dense fog developed early on March 20th, resulting in visibilities lowered to 1/4 mile or less across all of south-central and parts of southeastern Wisconsin. Air traffic was delayed or grounded at Madison's Truax Field (Dane Co.). Some school districts chose to delay the start of classes by 2 hours. Newspapers reported several vehicle accidents.

The radar

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

Open the radar archive at this moment

Event by event

12 dense fog. Local standard time, as filed.

Dense Fog, Walworth

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Walworth forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 42.669, -88.542 (the zone’s center; the record gives no point)

Dense Fog, Marquette

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Marquette forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.820, -89.399 (the zone’s center; the record gives no point)

Dense Fog, Green Lake

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Green Lake forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.800, -89.045 (the zone’s center; the record gives no point)

Dense Fog, Sauk

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Sauk forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.427, -89.948 (the zone’s center; the record gives no point)

Dense Fog, Columbia

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Columbia forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.467, -89.334 (the zone’s center; the record gives no point)

Dense Fog, Dodge

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Dodge forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.416, -88.707 (the zone’s center; the record gives no point)

Dense Fog, Iowa

When: March 23, 10:00 AM CST to 1:00 PM 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, Dane

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Dane forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.067, -89.418 (the zone’s center; the record gives no point)

Dense Fog, Jefferson

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Jefferson forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.021, -88.776 (the zone’s center; the record gives no point)

Dense Fog, Lafayette

When: March 23, 10:00 AM CST to 1:00 PM 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: March 23, 10:00 AM CST to 1:00 PM 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)

Dense Fog, Rock

When: March 23, 10:00 AM CST to 1:00 PM CST
Where: Rock forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 42.671, -89.072 (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 2003 Every state in 2003 This day in weather history Warnings in Wisconsin, March 2003

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: 5342736, 5346920, 5346921, 5346922, 5346923, 5346924, 5347017, 5347018, 5347019, 5347020, 5347021, 5347022.