Alert archive / Wisconsin / Flash Flood Warnings in 2021

Flash Flood Warning 7, NWS Green Bay, WI

August 27, 2021Waupaca County, Wisconsin

NWS Green Bay, WI issued this flash flood warning at Aug 27, 2021, 11:51 PM CDT for Waupaca County, Wisconsin. It was in force for 3 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 27, 2021, 11:51 PM CDT (04:51 UTC)
Expired: Aug 28, 2021, 3:00 AM CDT
In force: 3 hr
Issued by: NWS Green Bay, WI
Area: Storm-based polygon
Flood severity: None

County Waupaca County, WI

The radar

The Green Bay radar (KGRB), 63 km from the middle of the area, began a volume at 04:52 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.

What was reported inside it

Time	Report	Where	Remark
Aug 28, 12:00 AM CDT	FLASH FLOOD	Waupaca, WI	STREETS FLOODED AND MANHOLE COVERS LIFTED OFF.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 4.9 hours before the alert went out and 64 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 552 J/kg
Mixed-layer CIN: -77 J/kg
Mixed-layer LCL: 916 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 179 m²/s²
0-3 km storm-relative helicity: 278 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 1.6

Open this sounding in Storm Lab

The text

As transmitted.

002 
WGUS53 KGRB 280451
FFWGRB
WIC135-280800-
/O.NEW.KGRB.FF.W.0007.210828T0451Z-210828T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Green Bay WI
1151 PM CDT Fri Aug 27 2021

The National Weather Service in Green Bay has issued a

* Flash Flood Warning for...
  Central Waupaca County in northeastern Wisconsin...

* Until 300 AM CDT.

* At 1151 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Around 2 inches of rain have 
  fallen. The expected rainfall rate is 2 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.

  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...
  Waupaca, New London, Chain O' Lakes-King, Hartman Creek State 
  Park, Royalton, Manawa, Iola, King, Sheridan, Scandinavia, 
  Ogdensburg, Symco, Fitzgerald Corners and Northport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4455 8922 4455 8874 4450 8874 4448 8874
      4447 8874 4443 8874 4442 8874 4438 8874
      4437 8874 4432 8922 4448 8922

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...2 INCHES IN 1 HOUR

$$

Kurimski

4 follow-up statements

001 
WGUS73 KGRB 280527
FFSGRB

Flash Flood Statement
National Weather Service Green Bay WI
1227 AM CDT Sat Aug 28 2021

WIC135-280800-
/O.CON.KGRB.FF.W.0007.000000T0000Z-210828T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Waupaca WI-
1227 AM CDT Sat Aug 28 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 3 AM CDT EARLY THIS 
MORNING FOR CENTRAL WAUPACA COUNTY...

At 1227 AM CDT, local law enforcement reported flash flooding in 
Waupaca. Around 2 inches of rain have fallen. The expected rainfall 
rate is 2 inches in 1 hour. Additional rainfall amounts of 1 to 2 
inches are possible in the warned area. Flash flooding is already 
occurring.

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...
  Waupaca, New London, Chain O' Lakes-King, Hartman Creek State 
  Park, Royalton, Manawa, Iola, King, Sheridan, Scandinavia, 
  Ogdensburg, Symco, Fitzgerald Corners and Northport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4455 8922 4455 8874 4450 8874 4448 8874
      4447 8874 4443 8874 4442 8874 4438 8874
      4437 8874 4432 8922 4448 8922

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL...2 INCHES IN 1 HOUR

$$

Kurimski

534 
WGUS73 KGRB 280602
FFSGRB

Flash Flood Statement
National Weather Service Green Bay WI
102 AM CDT Sat Aug 28 2021

WIC135-280800-
/O.CON.KGRB.FF.W.0007.000000T0000Z-210828T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Waupaca WI-
102 AM CDT Sat Aug 28 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 3 AM CDT EARLY THIS 
MORNING FOR CENTRAL WAUPACA COUNTY...

At 102 AM CDT, local law enforcement reported flash flooding in 
Waupaca. Between 2 and 4 inches of rain have fallen. Even though the 
heavy rain has ended, flash
flooding is still occurring in Waupaca County.

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...
  Waupaca, New London, Chain O' Lakes-King, Hartman Creek State 
  Park, Royalton, Manawa, Iola, King, Sheridan, Scandinavia, 
  Ogdensburg, Symco, Fitzgerald Corners and Northport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4455 8922 4455 8874 4450 8874 4448 8874
      4447 8874 4443 8874 4442 8874 4438 8874
      4437 8874 4432 8922 4448 8922

FLASH FLOOD...OBSERVED

$$

Kurimski

109 
WGUS73 KGRB 280701
FFSGRB

Flash Flood Statement
National Weather Service Green Bay WI
201 AM CDT Sat Aug 28 2021

WIC135-280800-
/O.CON.KGRB.FF.W.0007.000000T0000Z-210828T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Waupaca WI-
201 AM CDT Sat Aug 28 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 3 AM CDT EARLY THIS 
MORNING FOR CENTRAL WAUPACA COUNTY...

At 201 AM CDT, local law enforcement reported flash flooding in 
Manawa. Between 2 and 4 inches of rain have fallen. Even though the 
heavy rain has ended, flash flooding is still occurring in Waupaca 
County.

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...
  Waupaca, New London, Chain O' Lakes-King, Hartman Creek State 
  Park, Royalton, Manawa, Iola, King, Sheridan, Scandinavia, 
  Ogdensburg, Symco, Fitzgerald Corners and Northport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4455 8922 4455 8874 4450 8874 4448 8874
      4447 8874 4443 8874 4442 8874 4438 8874
      4437 8874 4432 8922 4448 8922

FLASH FLOOD...OBSERVED

$$

Kurimski

220 
WGUS73 KGRB 280751
FFSGRB

Flash Flood Statement
National Weather Service Green Bay WI
251 AM CDT Sat Aug 28 2021

WIC135-280801-
/O.EXP.KGRB.FF.W.0007.000000T0000Z-210828T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Waupaca WI-
251 AM CDT Sat Aug 28 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 3 AM CDT EARLY THIS MORNING 
FOR CENTRAL WAUPACA COUNTY...

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

LAT...LON 4455 8922 4455 8874 4450 8874 4448 8874
      4447 8874 4443 8874 4442 8874 4438 8874
      4437 8874 4432 8922 4448 8922

$$

Kurimski

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 27, 7:25 PM CDT	Areal Flood Advisory	GRB	Outagamie, Portage, Shawano, Waupaca	2 hr
Aug 27, 7:52 PM CDT	Special Marine Warning	GRB		68 min
Aug 27, 7:55 PM CDT	Severe Thunderstorm Warning	GRB	Brown, Oconto, Outagamie, Shawano	65 min
Aug 27, 8:35 PM CDT	Special Weather Statement	GRB	Kewaunee	40 min
Aug 27, 9:08 PM CDT	Special Weather Statement	GRB	Calumet, Winnebago	52 min
Aug 27, 9:53 PM CDT	Areal Flood Advisory	GRB	Marathon, Portage, Waushara, Wood	3 hr
Aug 27, 9:59 PM CDT	Special Weather Statement	GRB	Calumet, Manitowoc	61 min
Aug 27, 10:36 PM CDT	Areal Flood Advisory	GRB	Calumet, Manitowoc	3 hr
Aug 27, 10:39 PM CDT	Areal Flood Advisory	GRB	Outagamie, Shawano, Waupaca, Winnebago	3 hr
Aug 27, 10:58 PM CDT	Flash Flood Warning	GRB	Portage, Wood	3 hr
Aug 27, 11:32 PM CDT	Special Weather Statement	GRB	Oconto, Waushara	58 min
Aug 28, 12:34 AM CDT	Flash Flood Warning	GRB	Brown, Outagamie	84 min
Aug 28, 1:38 AM CDT	Areal Flood Advisory	GRB	Brown, Calumet, Manitowoc	82 min
Aug 28, 7:41 AM CDT	River Flood Warning	GRB	Wood	21 days
Aug 28, 10:14 AM CDT	Beach Hazards Statement	GRB	Door	33 hr
Aug 28, 10:14 AM CDT	Small Craft Advisory	GRB		33 hr
Aug 28, 10:36 AM CDT	River Flood Warning	GRB	Wood	48 hr
Aug 28, 5:17 PM CDT	Special Weather Statement	GRB	Manitowoc	58 min

Nearby

Flash Flood Warnings in Wisconsin, 2021 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.