Alert archive / Wisconsin / Flash Flood Warnings in 2021

Flash Flood Warning 2, NWS Milwaukee, WI

August 28, 2021Fond du Lac County, Wisconsin

NWS Milwaukee, WI issued this flash flood warning at Aug 28, 2021, 11:26 PM CDT for Fond du Lac County, Wisconsin. It was in force for 85 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 28, 2021, 11:26 PM CDT (04:26 UTC)
Expired
Aug 29, 2021, 12:51 AM CDT
In force
85 min
Issued by
NWS Milwaukee, WI
Area
Storm-based polygon
Flood severity
None

County Fond du Lac County, WI

The radar

The Green Bay radar (KGRB), 70 km from the middle of the area, began a volume at 04:26 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

Green Bay/Straub, WI (KGRB), launched 00:00Z, 4.4 hours before the alert went out and 69 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, Green Bay/Straub, WI at 00:00Z on 2021-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 969 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, Green Bay/Straub, WI at 00:00Z on 2021-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 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
969 J/kg
Mixed-layer CIN
-84 J/kg
Mixed-layer LCL
1292 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
110 m²/s²
Significant tornado parameter
0.1
Supercell composite
2.0

Open this sounding in Storm Lab

The text

As transmitted.

908 
WGUS53 KMKX 290426
FFWMKX
WIC039-290730-
/O.NEW.KMKX.FF.W.0002.210829T0426Z-210829T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Milwaukee/Sullivan WI
1126 PM CDT Sat Aug 28 2021

The National Weather Service in Milwaukee/Sullivan has issued a

* Flash Flood Warning for...
  Northeastern Fond du Lac County in east central Wisconsin...

* Until 230 AM CDT.

* At 1126 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Flash flooding is ongoing or 
  expected to begin shortly. Radar indicated between 2 and 3 inches 
  has fallen in this area in the last 2 hours.  Additional rainfall 
  of up to one half inch is possible.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  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...
  Southern Lake Winnebago, Van Dyne, Pipe, Johnsburg and Marytown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4384 8859 4389 8869 4389 8860 4389 8858
      4389 8855 4389 8854 4389 8851 4389 8840
      4394 8840 4394 8838 4394 8831 4394 8820
      4394 8817 4394 8816 4391 8816 4389 8816
      4388 8816

FLASH FLOOD...RADAR INDICATED

$$

KAVINSKY
2 follow-up statements
932 
WGUS73 KMKX 290520
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
1220 AM CDT Sun Aug 29 2021

WIC039-290730-
/O.CON.KMKX.FF.W.0002.000000T0000Z-210829T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Fond du Lac WI-
1220 AM CDT Sun Aug 29 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 230 AM CDT EARLY THIS 
MORNING FOR NORTHEASTERN FOND DU LAC COUNTY...

At 1220 AM CDT, Local law enforcement reported several roads remain 
closed and barricaded in far northeast Fond du Lac county, including 
Kiel Road between Town Hall Road and County Road W. Additional 
rainfall up to one half inch is possible through 230 am CDT from 
scattered thunderstorms.  Localized flooding is ongoing or expected 
to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Law enforcement reported.

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...
  Southern Lake Winnebago, Van Dyne, Pipe, Johnsburg and Marytown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4384 8859 4389 8869 4389 8840 4394 8840
      4394 8838 4394 8831 4394 8820 4394 8817
      4394 8816 4391 8816 4389 8816 4388 8816

FLASH FLOOD...OBSERVED

$$

KAVINSKY
429 
WGUS73 KMKX 290551
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
1251 AM CDT Sun Aug 29 2021

WIC039-290601-
/O.CAN.KMKX.FF.W.0002.000000T0000Z-210829T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Fond du Lac WI-
1251 AM CDT Sun Aug 29 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN FOND DU LAC 
COUNTY...

Flood waters have receded. Flooding is no longer expected to pose a 
threat. Please continue to heed any remaining road closures.

LAT...LON 4384 8859 4389 8869 4389 8840 4394 8840
      4394 8838 4394 8831 4394 8820 4394 8817
      4394 8816 4391 8816 4389 8816 4388 8816

$$

KAVINSKY

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 28, 11:36 PM CDTAreal Flood AdvisoryMKXSheboygan3 hr

Nearby

Flash Flood Warnings in Wisconsin, 2021Every flash flood warning in 2021

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.