Wisconsin, 2001

Damaging Winds in Wisconsin, September 7, 2001

September 7, 2001 · NWS MKX · 5 events in 5 counties and zones

The first of two rounds of severe thunderstorms to affect southern Wisconsin on September 7th struck parts of the south-central and southeast counties in the early afternoon hours. ).

Where it happened

Every event with a place to put it. 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

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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
5

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.

The first of two rounds of severe thunderstorms to affect southern Wisconsin on September 7th struck parts of the south-central and southeast counties in the early afternoon hours. Powerful straight-line downburst winds toppled many large trees east of Montello (Marquette Co.), in the northwest part of Green Lake County north of Princeton, in the Windsor area (Dane Co.), and in the Beaver Dam area (Dodge Co.). Law enforcement officials and trained spotters estimated wind gusts to be in the 50 to 52 knot range (58 to 60 mph). The storms weakened as they moved east into Fond du Lac and Jefferson Counties where winds gusts were only in the 30 to 40 knot range (35 to 46 mph). Synoptically, the severe storms developed ahead of a cold front pushing east across Wisconsin, while the parent low pressure moved northeast through northwest Wisconsin. Surface dewpoints were in the lower 70s with maximum air temperatures in the mid 80s.

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 Sep 7, 2:00 AM CST, 9 hours 35 minutes earlier.

Area forecast discussion, Sep 7, 2:00 AM CST, 9 hours 35 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
300 AM CDT FRI SEP 7 2001

FCST FOCUS IS ON TIMING OF RN EVENTS WITHIN A VERY COMPLICATED WX
PATTERN.

EVOLUTION OF UPPER LOW AGAIN A BIT SLOWER ON THE 00Z MODEL RUNS.  AS
PREVIOUSLY STATED...THIS PROBLEM IS CONSISTENT WITH A DIGGING VERY
LARGE SCALE SYSTEM SUCH AS THIS.  FIRST BIG S/W HAS MOVED N OF THE
CWA...ANOTHER APPEARS TO BE FOLLOWING CLOSE ON ITS HEALS...PER THE
WATER VAPOR IMAGERY.  THIS HAS RE-IGNIGHTED SOME ACTIVITY ACRS NRN
IL WITH A MOVEMENT NE INTO THE CWA.  ANOTHER S/W OVER NEB IS PROGD
TO CLIP WRN WI ON ITS WAY NE TODAY AND DRAG A TAIL OF S/W ENERGY ACRS
THE CWA TONIGHT. IT IS ALL THESE LEADING PIECES OF ENERGY THAT MAKE
TIMING OF PCPN EXTREMEMLY DIFFICULT.  IT APPEARS THE WRN CWA WILL
HAVE A BETTER CHANCE FOR PCPN THRU SAT DUE TO THE ADJACENCY OF THE
FRONT. THE EAST MAY GET INTO A BIT OF A DRY SLOT AFTER THIS MORNINGS
CONVECTION MOVES THROUGH.  WILL THEREFORE END UP GOING MORE CHCY IN
THE EAST AND LIKELY IN THE WEST THUR THE FCST PDS.

THE MODELS ARE IN RSNBL AGREEMENT THAT THE SFC LOW WILL CONSOLIDATE
INTO A NICE CENTER BY MIDDAY SAT OVER NRN WI OR NE MN. THE ATTENDANT
CDFNT WILL SWEEP THROUGH...EXITING THE EAST SAT EVENING. THE HUGE
UPR LOW...HOWEVER...IS HANGING WAY BACK AND DOESN/T COME THROUGH
UNTIL EARLY MONDAY MORNING.  UNDER THAT UPPER LOW HOWEVER...IS A LOT
OF COLD AIR ADVECTION WITH HIGH PRESSURE PROVIDING STRONG
SUBSIDENCE.  THE PASSAGE OF THE UPPER LOW SHOULD ONLY BRING A SML
THREAT OF SHOWERS.

TEMPS ALL DEPENDENT ON TIMING OF CDFNT.  DUE TO THE SLOWER
EVOLUTION...WILL BUMP TEMPS ACCORDINGLY.

.MKX...NONE.

DAVIS

The radar

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

Open the radar archive at this moment

Event by event

5 thunderstorm wind. Local standard time, as filed.

Thunderstorm Wind, Columbia

When
September 7, 11:35 AM CST to 11:45 AM CST
Where
Columbia County, Lodi
Measured
52 kt (60 mph)
Reported by
LAW ENFORCEMENT
Coordinates
43.317, -89.517

Thunderstorm Wind, Marquette

When
September 7, 11:50 AM CST
Where
Marquette County, 5 mi E of Montello
Measured
50 kt (58 mph)
Reported by
TRAINED SPOTTER
Coordinates
43.800, -89.217

Thunderstorm Wind, Green Lake

When
September 7, 11:50 AM CST to 12:00 PM CST
Where
Green Lake County, Princeton
Measured
52 kt (60 mph)
Reported by
EMERGENCY MANAGER
Coordinates
43.850, -89.117

Thunderstorm Wind, Dane

When
September 7, 11:55 AM CST
Where
Dane County, Windsor
Measured
50 kt (58 mph)
Reported by
TRAINED SPOTTER
Coordinates
43.217, -89.333

Thunderstorm Wind, Dodge

When
September 7, 1:07 PM CST
Where
Dodge County, Beaver Dam
Measured
52 kt (60 mph)
Reported by
LAW ENFORCEMENT
Coordinates
43.467, -88.833

What these are

Thunderstorm Wind
Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Wisconsin in 2001Every state in 2001This day in weather historyWarnings in Wisconsin, September 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 2026-09-24. Each event’s entry at NCEI: 5269165, 5269164, 5269167, 5269166, 5269168.