Alert archive / Wisconsin / Flash Flood Warnings in 2026

Flash Flood Warning 21, NWS Milwaukee, WI

September 4, 2026Sheboygan County, Wisconsin

NWS Milwaukee, WI issued this flash flood warning at Sep 4, 2026, 5:56 AM CDT for Sheboygan County, Wisconsin. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 4, 2026, 5:56 AM CDT (10:56 UTC)
Expired
Sep 4, 2026, 9:00 AM CDT
In force
3 hr
Issued by
NWS Milwaukee, WI
Area
Storm-based polygon
Flood severity
None

County Sheboygan County, WI

The radar

The Green Bay radar (KGRB), 89 km from the middle of the area, began a volume at 10:59 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 10.9 hours before the alert went out and 325 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2026-09-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3157 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2026-09-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 63 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
3157 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
1516 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
63 m²/s²
0-3 km storm-relative helicity
92 m²/s²
Significant tornado parameter
0.4
Supercell composite
5.5

Open this sounding in Storm Lab

The text

As transmitted.

313 
WGUS53 KMKX 041056
FFWMKX
WIC117-041400-
/O.NEW.KMKX.FF.W.0021.260904T1056Z-260904T1400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Milwaukee/Sullivan WI
556 AM CDT Fri Sep 4 2026

The National Weather Service in Milwaukee/Sullivan has issued a

* Flash Flood Warning for...
  Northeastern Sheboygan County in east central Wisconsin...

* Until 900 AM CDT.

* At 556 AM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Between 1 and 3 inches of rain
  have fallen. The expected rainfall rate is 0.5 to 1.5 inches in 1
  hour. Additional rainfall amounts of 1 to 2 inches are possible in
  the warned area. Flash flooding is ongoing or expected to begin
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  IMPACT...Flash flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other poor
           drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Sheboygan, Plymouth, Sheboygan Falls, Howards Grove, Oostburg,
  Kohler, Elkhart Lake, Waldo, Glenbeulah, Johnsonville, Gibbsville
  and Haven.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4361 8776 4366 8792 4374 8806 4389 8808
      4389 8773 4382 8773 4380 8771 4379 8773
      4379 8771 4378 8771 4374 8774 4375 8772
      4374 8771 4375 8770 4373 8771 4371 8770
      4371 8771 4370 8771 4370 8770 4369 8770

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...0.5-1.5 INCHES IN 1 HOUR

$$

Wood
3 follow-up statements
761 
WGUS73 KMKX 041151
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
651 AM CDT Fri Sep 4 2026

WIC117-041400-
/O.CON.KMKX.FF.W.0021.000000T0000Z-260904T1400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sheboygan WI-
651 AM CDT Fri Sep 4 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 9 AM CDT THIS MORNING
FOR NORTHEASTERN SHEBOYGAN COUNTY...

At 651 AM CDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 1 and 3 inches of rain have
fallen. The expected rainfall rate is 0.5 to 1.5 inches in 1 hour.
Additional rainfall amounts of 1 to 2 inches are possible in the
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar indicated.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Sheboygan, Plymouth, Sheboygan Falls, Howards Grove, Oostburg,
  Kohler, Elkhart Lake, Waldo, Glenbeulah, Johnsonville, Gibbsville
  and Haven.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4361 8776 4366 8792 4374 8806 4389 8808
      4389 8773 4382 8773 4380 8771 4379 8773
      4379 8771 4378 8771 4374 8774 4375 8772
      4374 8771 4375 8770 4373 8771 4371 8770
      4371 8771 4370 8771 4370 8770 4369 8770

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...0.5-1.5 INCHES IN 1 HOUR

$$

Wood
924 
WGUS73 KMKX 041256
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
756 AM CDT Fri Sep 4 2026

WIC117-041400-
/O.CON.KMKX.FF.W.0021.000000T0000Z-260904T1400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sheboygan WI-
756 AM CDT Fri Sep 4 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 9 AM CDT THIS MORNING
FOR NORTHEASTERN SHEBOYGAN COUNTY...

At 756 AM CDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 1 and 3 inches of rain have
fallen. The expected rainfall rate is 0.5 to 1.5 inches in 1 hour.
Additional rainfall amounts of 1 to 2 inches are possible in the
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar indicated.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Sheboygan, Plymouth, Sheboygan Falls, Howards Grove, Oostburg,
  Kohler, Elkhart Lake, Waldo, Glenbeulah, Johnsonville, Gibbsville
  and Haven.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4361 8776 4366 8792 4374 8806 4389 8808
      4389 8773 4382 8773 4380 8771 4379 8773
      4379 8771 4378 8771 4374 8774 4375 8772
      4374 8771 4375 8770 4373 8771 4371 8770
      4371 8771 4370 8771 4370 8770 4369 8770

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...0.5-1.5 INCHES IN 1 HOUR

$$

Wood
719 
WGUS73 KMKX 041353
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
853 AM CDT Fri Sep 4 2026

WIC117-041403-
/O.EXP.KMKX.FF.W.0021.000000T0000Z-260904T1400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sheboygan WI-
853 AM CDT Fri Sep 4 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 9 AM CDT THIS MORNING FOR
NORTHEASTERN SHEBOYGAN COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.

&&

LAT...LON 4361 8776 4366 8792 4374 8806 4389 8808
      4389 8773 4382 8773 4380 8771 4379 8773
      4379 8771 4378 8771 4374 8774 4375 8772
      4374 8771 4375 8770 4373 8771 4371 8770
      4371 8771 4370 8771 4370 8770 4369 8770

$$

Wood

The office that day

Everything else NWS Milwaukee, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 3, 8:54 PM CDTSpecial Weather StatementMKXMarquette51 min
Sep 3, 10:20 PM CDTSpecial Weather StatementMKXFond du Lac40 min
Sep 3, 10:25 PM CDTSevere Thunderstorm WarningMKXDodge, Fond du Lac, Green Lake35 min
Sep 3, 10:53 PM CDTSevere Thunderstorm Warning Considerable damage threatMKXDodge, Fond du Lac, Washington52 min
Sep 3, 11:23 PM CDTSevere Thunderstorm Warning Considerable damage threatMKXDodge, Washington67 min
Sep 3, 11:30 PM CDTAreal Flood AdvisoryMKXDodge, Fond du Lac, Washington2 hr
Sep 3, 11:45 PM CDTSevere Thunderstorm Warning Destructive damage threatMKXDodge, Washington30 min
Sep 4, 12:04 AM CDTSevere Thunderstorm Warning Considerable damage threatMKXDodge, Milwaukee, Ozaukee, Washington, Waukesha56 min
Sep 4, 12:28 AM CDTAreal Flood AdvisoryMKXMilwaukee, Ozaukee, Washington, Waukesha103 min
Sep 4, 12:33 AM CDTSpecial Weather StatementMKXFond du Lac42 min
Sep 4, 12:38 AM CDTSevere Thunderstorm WarningMKXFond du Lac52 min
Sep 4, 12:50 AM CDTSpecial Marine WarningMKX85 min
Sep 4, 12:54 AM CDTSevere Thunderstorm WarningMKXMilwaukee, Ozaukee, Washington, Waukesha51 min
Sep 4, 1:03 AM CDTSevere Thunderstorm WarningMKXFond du Lac, Sheboygan42 min
Sep 4, 1:11 AM CDTSevere Thunderstorm WarningMKXFond du Lac, Sheboygan49 min
Sep 4, 1:17 AM CDTSpecial Marine WarningMKX118 min
Sep 4, 1:34 AM CDTSevere Thunderstorm WarningMKXSheboygan41 min
Sep 4, 1:40 AM CDTSevere Thunderstorm Warning Considerable damage threatMKXFond du Lac, Green Lake, Marquette80 min
Sep 4, 2:11 AM CDTSpecial Marine WarningMKX64 min
Sep 4, 2:14 AM CDTSevere Thunderstorm WarningMKXSheboygan16 min
Sep 4, 2:35 AM CDTAreal Flood AdvisoryMKXFond du Lac2 hr
Sep 4, 2:37 AM CDTSevere Thunderstorm WarningMKXDodge, Fond du Lac, Ozaukee, Sheboygan, Washington53 min
Sep 4, 3:08 AM CDTSpecial Marine WarningMKX97 min
Sep 4, 5:29 AM CDTAreal Flood AdvisoryMKXSheboygan3 hr
Sep 4, 6:26 AM CDTAreal Flood AdvisoryMKXFond du Lac, Green Lake, Marquette3 hr
Sep 4, 7:40 AM CDTAreal Flood AdvisoryMKXFond du Lac2 hr
Sep 4, 8:25 AM CDTSpecial Marine WarningMKX65 min
Sep 4, 9:24 AM CDTSpecial Weather StatementMKXDane51 min
Sep 4, 9:35 AM CDTSpecial Weather StatementMKXWaukesha40 min
Sep 4, 10:39 AM CDTSpecial Weather StatementMKXMilwaukee, Racine51 min
Sep 4, 10:41 AM CDTSpecial Marine WarningMKX33 min

Nearby

Flash Flood Warnings in Wisconsin, 2026Every flash flood warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.