Flooding and Hail in Wisconsin, June 17 to 18, 2001

Name: Flooding and Hail in Wisconsin, June 17 to 18, 2001
Start: 2001-06-17T19:02
End: 2001-06-18T03:00
Location: Wisconsin

June 17 to 18, 2001 · NWS MKX · 16 events in 7 counties and zones

Scattered severe thunderstorms, with large hail and damaging, straight-line, down-burst winds, affected parts of south-central and southeast Wisconsin. ).

Where it happened

Every event with a place to put it; 5 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: 1
Property damage: $200,000
Crop damage: None recorded
Events: 16

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.

Scattered severe thunderstorms, with large hail and damaging, straight-line, down-burst winds, affected parts of south-central and southeast Wisconsin. There were many reports of toppled trees, and hail stones reached golf-ball size (1.75 inches in diameter) southeast of Portage (Columbia Co.). One person was injured between Reedsburg and Baraboo when a wind-toppled tree fell on their car. Torrential rains accompanied some of the storms, resulting in urban and small stream flooding in and around Randolph and Fox Lake in northwest Dodge County. Three-fourths of an inch of rain fell in 25 minutes in Randolph and up to 2 inches fell around Fox Lake. Up to 1.80 inches of rain fell in a short period of time in the Baraboo to Lake Delton area of Sauk County, resulting in urban and small stream flooding in that county. Water depths affected roads in northeast Sauk and northwest Dodge Counties where it was reported to be 6 inches to 2 feet deep. Lightning-initiated fires destroyed two barns on separate farms near Mifflan (Iowa Co.).Synoptically, an upper-level, short-wave trough moved through the Great Lakes region. Instability along the trough was sufficient to allow thunderstorm development. The thunderstorm cells moved southeastward.

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 Jun 17, 6:05 PM CST, 57 minutes earlier.

Area forecast discussion, Jun 17, 6:05 PM CST, 57 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
705 PM CDT SUN JUN 17 2001

SHORT TERM UPDATE...
FOCUS IS ON THUNDERSTORM DEVELOPMENT THIS EVENING.  ONE WEAK
SHORTWAVE IN ZONAL JET PUSHING INTO S WI BY MIDNIGHT.  ENOUGH MID
LEVEL INSTABILITY...ALONG WITH NOSE OF 850 MB LLJ PUSHING INTO THE
FORECAST AREA.  AS A RESULT EXPECT ELEVATED THUNDERSTORMS TO
CONTINUE TO DEVELOP.  HOWEVER SHORTWAVE QUICKLY OUTRUNS BEST LOW
LEVEL CONVERGENCE. QUESTION IS WHAT WILL HAPPEN AFTER SHORTWAVE
PUSHES EAST...WHEN 850 MB CONVERGENCE CONTINUES.  WILL THE WEAK
MID/UPPER LEVEL SUBSIDENCE OFFSET THE LOW LEVEL CONVERGENCE?  WILL
MONITOR DEVELOPING SITUATION...AND NEW MODEL RUNS. NEXT UPSTREAM
SHORTWAVE OVER WY SHOULD AFFECT US VERY LATE TONIGHT. RIGHT NOW ANY
SEVERE THREAT FOR MOST OF TONIGHT WOULD BE MARGINAL HAIL.  HOWEVER...
SOME STEEP LAPSE RATES IN LOW LEVELS AND SOMEWHAT OF AN INVERTED V
SOUNDING AT LOW LEVELS...SO SOME GUST POTENTIAL EXITS.

REST OF FORECAST DISCUSSION FROM AFTERNOON FOLLOWS...

FORECAST FOCUS ON HEAVY RAIN POTENTIAL FOR NEXT SEVERAL DAYS.

THIS MODEL RUN A BIT LESS GENEROUS WITH PRECIPITATION OVER OUR CWA
SAVE FOR THE NGM MODEL. EVEN THIS WETTER MODEL PRODUCES LESS THAN
ONE INCH OF PRECIPITATION OVER PORTIONS OF THE CWA LATE TONIGHT AND
INTO MONDAY.

THE AVN AND ETA KEEP THE BEST ENERGY TO THE NORTH THROUGH THE
PERIOD AS SEEN WITH THE VIGOROUS 500MB VORT MAXS MOVING THROUGH
NORTHERN WISCONSIN. BULK OF THE PREIPITATION FOLLOWS THE ENERGY TO
THE NORTH. NEW BUFKIT SOUNDINGS NOW SHOW PREIPITABLE WATER AT OR
BELOW 1.5 INCHES...MUCH LOWER THAN THE PREVIOUS RUN. FOR THESE
REASONS WILL NOT REISSUE ESF AND WILL TAKE OUT HEAVY PRECIPITATION
WORDING. HOWEVER SITUATION MAY CHANGE WITH FUTURE MODEL RUNS.

ALTHOUGH ATMOSPHERE LESS STABLE THAN YESTERDAY/S RUN...AND BEST
INSTABILITY IS TO OUR WEST...SPC HAS PUT US IN MODERATE RISK FOR
DAY 2 MONDAY AND MONDAY NIGHT. IF STORMS DO FIRE THEY WILL MOST
LIKELY BE SEVERE DUE TO THE HIGH HELICITY VALUES. HAVE LOWERED
PRECIPITATION CHANCES ON MONDAY AND MONDAY NIGHT DUE TO LOWERED
INSTABILITY AND BEST ENERGY PASSING TO THE NORTH. HOWEVER HAVE
DECIDED TO KEEP SEVERE WORDING IN WITH 1500 J/KG CAPE...-2 TO -3
LIFTED INDEX...AND 400 HELICITY VALUES. BEST CHANCE OF PRECIPITATION
WILL PROBABLY BE MONDAY NIGHT AS THE FRONT APPROACHES LATE IN THE
NIGHTTIME HOURS.

TUESDAY LOOKS COOLER THAN PREVIOUS FEW DAYS WITH COLD FRONT MOVING
THROUGH THE AREA EARLY IN THE DAY. NGM MOS NUMBERS A BIT TOO LOFTY
CONSIDERING THE FRONTAL PASSAGE AND CLOUD COVER. WENT WITH THE
COOLER AVN MOS AS ETA 2M TEMPS AGREE WITH THESE COOLER NUMBERS.

REST OF THE WEEK LOOKS TO BE COOLER WITH A CHANCE FOR SHOWERS EACH
DAY AS A SERIES OF DISTURBANCES MOVE THROUGH WISCONSIN WITH THE COOL
UPPER LEVEL NORTHWEST FLOW. HOWEVER LOOKS LIKE HIGH PRESSURE WILL
DOMINATE AND PROVIDE FOR A NICE WEEKEND.

COO~RDINATION WITH GRB/ARX.

.MKX...NONE

HENTZ

The radar

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

Open the radar archive at this moment

Event by event

8 hail, 3 flood, 3 thunderstorm wind, 2 lightning. Local standard time, as filed.

Lightning, Iowa

When: June 17, 7:02 PM CST
Where: Iowa County, 1 mi E of Mifflan
Property damage: $100,000
Reported by: EMERGENCY MANAGER
Coordinates: 43.533, -89.283

Lightning, Iowa

When: June 17, 7:10 PM CST
Where: Iowa County, 3 mi NE of Mifflan
Property damage: $100,000
Reported by: EMERGENCY MANAGER
Coordinates: 43.533, -89.000

Hail, Sauk

When: June 17, 8:30 PM CST to 8:35 PM CST
Where: Sauk County, Baraboo
Measured: 1 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 43.400, -88.833

Flood, Sauk

When: June 17, 8:40 PM CST to 11:00 PM CST
Where: Sauk County, Baraboo
Reported by: LAW ENFORCEMENT
Coordinates: 43.427, -89.948 (the zone’s center; the record gives no point)

Flood, Columbia

When: June 17, 8:45 PM CST to 11:00 PM CST
Where: Columbia County, Portage
Reported by: LAW ENFORCEMENT
Coordinates: 43.133, -88.217

Hail, Sauk

When: June 17, 8:50 PM CST
Where: Sauk County, 6 mi SE of Baraboo
Measured: 1 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 43.317, -88.283

Thunderstorm Wind, Sauk

When: June 17, 8:57 PM CST to 9:05 PM CST
Where: Sauk County, Reedsburg
Measured: 54 kt (62 mph)
Injuries: 1 direct, 0 indirect
Reported by: LAW ENFORCEMENT
Coordinates: 43.150, -88.417

Hail, Columbia

When: June 17, 10:28 PM CST
Where: Columbia County, 8 mi SE of Portage
Measured: 1.75 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 43.000, -87.967

Hail, Columbia

When: June 17, 11:21 PM CST
Where: Columbia County, Pardeeville
Measured: 1 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 43.467, -89.334 (the zone’s center; the record gives no point)

Thunderstorm Wind, Dodge

When: June 17, 11:50 PM CST
Where: Dodge County, Randolph
Measured: 52 kt (60 mph)
Reported by: LAW ENFORCEMENT
Coordinates: 43.416, -88.707 (the zone’s center; the record gives no point)

Flood, Dodge

When: June 18, 12:00 AM CST to 3:00 AM CST
Where: Dodge County, Randolph
Reported by: LAW ENFORCEMENT
Coordinates: 43.416, -88.707 (the zone’s center; the record gives no point)

Hail, Dodge

When: June 18, 12:09 AM CST to 12:15 AM CST
Where: Dodge County, 5 mi S of Beaver Dam
Measured: 0.75 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 43.467, -89.733

Hail, Waukesha

When: June 18, 12:47 AM CST
Where: Waukesha County, Stonebank
Measured: 0.88 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 43.533, -90.000

Thunderstorm Wind, Washington

When: June 18, 1:00 AM CST
Where: Washington County, 1 mi S of Slinger
Measured: 52 kt (60 mph)
Reported by: LAW ENFORCEMENT
Coordinates: 43.400, -89.650

Hail, Waukesha

When: June 18, 1:00 AM CST
Where: Waukesha County, Sussex
Measured: 1 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 43.018, -88.304 (the zone’s center; the record gives no point)

Hail, Milwaukee

When: June 18, 1:15 AM CST
Where: Milwaukee County, West Allis
Measured: 0.88 in hail
Reported by: AMATEUR RADIO
Coordinates: 43.467, -89.333

What these are

Lightning: A lightning strike that killed, injured or caused damage.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
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

Every storm in Wisconsin in 2001 Every state in 2001 This day in weather history Warnings in Wisconsin, June 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: 5256569, 5256570, 5256153, 5256154, 5256157, 5256155, 5256156, 5256158, 5256159, 5256160, 5256564, 5256563, 5256566, 5256565, 5256567, 5256568.