Alert archive / Wisconsin / Flash Flood Warnings in 2021

Flash Flood Warning 3, NWS La Crosse, WI

August 7, 2021La Crosse County, Monroe County, Wisconsin

NWS La Crosse, WI issued this flash flood warning at Aug 7, 2021, 3:23 PM CDT for La Crosse County, Monroe County, Wisconsin. It was in force for 3 hr. 13 reports 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 7, 2021, 3:23 PM CDT (20:23 UTC)
Expired: Aug 7, 2021, 6:30 PM CDT
In force: 3 hr
Issued by: NWS La Crosse, WI
Area: Storm-based polygon
Flood severity: None

Counties La Crosse County, WI, Monroe County, WI

The radar

The La Crosse radar (KARX), 9 km from the middle of the area, began a volume at 20:23 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 7, 3:25 PM CDT	HEAVY RAIN 3.55	1 W West Salem, WI	RAINFALL 7AM THRU 325PM.
Aug 7, 3:28 PM CDT	FLASH FLOOD	1 Ssw La Crosse, WI	REPORT FROM MPING: STREET/ROAD FLOODING; STREET/ROAD CLOSED; VEHICLES STRANDED.
Aug 7, 3:29 PM CDT	HEAVY RAIN 4.75	2 Se Onalaska, WI
Aug 7, 3:30 PM CDT	HEAVY RAIN 4.5	2 Nnw Onalaska, WI
Aug 7, 3:45 PM CDT	FLASH FLOOD	4 Se La Crosse, WI	MUDSLIDE/WASHOUT ALONG STATE HIGHWAY 33 AT THE BOTTOM OF IRISH HILL.
Aug 7, 3:45 PM CDT	FLASH FLOOD	5 Sse La Crosse, WI	BOULDERS IN THE ROAD AT THE HIGHWAY 14/61 SPLIT ON THE VERY SOUTH SIDE OF LA CROSSE.
Aug 7, 3:50 PM CDT	FLASH FLOOD	3 S Saint Joseph, WI	PORTIONS OF COUNTY HIGHWAY NN WASHED OUT PER FACEBOOK POST. TIME ESTIMATED.
Aug 7, 4:00 PM CDT	FLASH FLOOD	1 Nne Melvina, WI	REPORTS OF WATER AND DEBRIS ACROSS STATE HIGHWAY 27 NEAR MELVINA.
Aug 7, 4:00 PM CDT	FLASH FLOOD	3 Wnw Melvina, WI	MUDSLIDE WITH ROCKS ACROSS COUNTY HIGHWAY X.
Aug 7, 4:00 PM CDT	FLASH FLOOD	5 Nnw Melvina, WI	WATER OVER BOTH LANES OF COUNTY HIGHWAY J JUST WEST OF STATE HIGHWAY 27.
Aug 7, 4:00 PM CDT	HEAVY RAIN 5.5	1 Nne Barre Mills, WI
Aug 7, 4:50 PM CDT	HEAVY RAIN 6.5	3 S La Crosse, WI	ESTIMATED - BUCKET REPORT.
Aug 7, 5:42 PM CDT	HEAVY RAIN 5.21	2 Ssw Saint Joseph, WI

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 12:00Z, 8.4 hours before the alert went out and 249 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: 20 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 656 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 72 m²/s²
0-3 km storm-relative helicity: 103 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

710 
WGUS53 KARX 072023
FFWARX
WIC063-081-072330-
/O.NEW.KARX.FF.W.0003.210807T2023Z-210807T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service La Crosse WI
323 PM CDT Sat Aug 7 2021

The National Weather Service in La Crosse has issued a

* Flash Flood Warning for...
  Southern La Crosse County in west central Wisconsin...
  Southwestern Monroe County in west central Wisconsin...

* Until 630 PM CDT.

* At 323 PM CDT, the public reported thunderstorms producing heavy 
  rain across the warned area. Between 2 and 5 inches of rain have 
  fallen. 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...Public 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...
  La Crosse, Onalaska, Holmen, West Salem, Bangor, Cashton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4373 9126 4377 9124 4379 9126 4392 9131
      4393 9121 4390 9091 4389 9065 4373 9064

FLASH FLOOD...OBSERVED

$$

KDS

2 follow-up statements

728 
WGUS73 KARX 072111
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
411 PM CDT Sat Aug 7 2021

WIC063-081-072330-
/O.CON.KARX.FF.W.0003.000000T0000Z-210807T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Crosse WI-Monroe WI-
411 PM CDT Sat Aug 7 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM CDT THIS 
EVENING FOR SOUTHERN LA CROSSE AND SOUTHWESTERN MONROE COUNTIES...

At 411 PM CDT, the public reported thunderstorms producing heavy 
rain across the warned area. Between 3 and 6 inches of rain have 
fallen. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Public reported. Multiple roads in and around the region
         are impassable due to flood waters or mudslides,
         including within the La Crosse area.

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...
  La Crosse, Onalaska, Holmen, West Salem, Bangor, Cashton, La 
  Crosse Airport, French Island, Brice Prairie, Medary, Leon, 
  Portland, Rockland, Melvina, Middle Ridge, Newburg Corners, The 
  Coulee Experimental Forest, St Joseph, County Roads G And H and 
  Norskedalen.

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 4373 9126 4377 9124 4379 9126 4392 9131
      4393 9121 4390 9091 4389 9065 4373 9064

FLASH FLOOD...OBSERVED

$$

ARX

416 
WGUS73 KARX 072324
FFSARX

Flash Flood Statement
National Weather Service La Crosse WI
624 PM CDT Sat Aug 7 2021

WIC063-081-072334-
/O.EXP.KARX.FF.W.0003.000000T0000Z-210807T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
La Crosse WI-Monroe WI-
624 PM CDT Sat Aug 7 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 630 PM CDT THIS EVENING FOR 
SOUTHERN LA CROSSE AND SOUTHWESTERN MONROE COUNTIES...

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

A Flash Flood Watch remains in effect until 1000 AM CDT Sunday for 
portions of northeast Iowa, southeast Minnesota and Wisconsin.

LAT...LON 4373 9126 4377 9124 4379 9126 4392 9131
      4393 9121 4390 9091 4389 9065 4373 9064

$$

ARX

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 7, 6:26 AM CDT	Special Weather Statement	ARX	Buffalo	34 min
Aug 7, 7:40 AM CDT	Special Weather Statement	ARX	La Crosse	35 min
Aug 7, 9:17 AM CDT	Special Weather Statement	ARX	Juneau	28 min
Aug 7, 10:12 AM CDT	Special Weather Statement	ARX	Adams	33 min
Aug 7, 11:17 AM CDT	Special Weather Statement	ARX	Crawford	28 min
Aug 7, 11:24 AM CDT	Severe Thunderstorm Warning	ARX	La Crosse, Vernon	27 min
Aug 7, 11:26 AM CDT	Severe Thunderstorm Warning	ARX	Crawford, Richland, Vernon	21 min
Aug 7, 12:19 PM CDT	Special Weather Statement	ARX	Richland	26 min
Aug 7, 12:59 PM CDT	Areal Flood Advisory	ARX	Buffalo	2 hr
Aug 7, 1:17 PM CDT	Severe Thunderstorm Warning	ARX	Richland, Vernon	58 min
Aug 7, 1:48 PM CDT	Special Weather Statement	ARX	La Crosse	27 min
Aug 7, 2:14 PM CDT	Special Weather Statement	ARX	La Crosse	31 min
Aug 7, 2:23 PM CDT	Areal Flood Advisory	ARX	La Crosse, Trempealeau	112 min
Aug 7, 3:02 PM CDT	River Flood Warning	ARX	Monroe, Vernon	21 days
Aug 7, 3:02 PM CDT	River Flood Warning	ARX	Vernon	4 days
Aug 7, 3:02 PM CDT	River Flood Warning	ARX	Richland, Vernon	4 days
Aug 7, 3:02 PM CDT	River Flood Warning	ARX	Richland, Vernon	61 hr
Aug 7, 3:02 PM CDT	River Flood Warning	ARX	Buffalo, Trempealeau	19 hr
Aug 7, 3:07 PM CDT	Areal Flood Advisory	ARX	La Crosse	74 min
Aug 7, 3:17 PM CDT	Special Weather Statement	ARX	Vernon	73 min
Aug 7, 3:35 PM CDT	Severe Thunderstorm Warning	ARX	Vernon	55 min
Aug 7, 3:52 PM CDT	Severe Thunderstorm Warning	ARX	Crawford	38 min
Aug 7, 4:00 PM CDT	Tornado Warning	ARX	Crawford	30 min
Aug 7, 4:05 PM CDT	Severe Thunderstorm Warning	ARX	Richland	40 min
Aug 7, 4:19 PM CDT	Tornado Warning	ARX	Crawford, Grant	41 min
Aug 7, 4:27 PM CDT	Flash Flood Warning	ARX	Vernon	3 hr
Aug 7, 4:56 PM CDT	Tornado Warning Tornado observed	ARX	Grant	19 min
Aug 7, 5:53 PM CDT	Severe Thunderstorm Warning	ARX	Juneau, Monroe, Vernon	37 min
Aug 7, 6:18 PM CDT	Flash Flood Watch	ARX	Adams, Buffalo, Clark, Crawford, Jackson, Juneau and 5 more	35 hr

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.