Alert archive / Wisconsin / Flash Flood Warnings in 2018

Flash Flood Warning 5, NWS Milwaukee, WI

August 20, 2018Dane County, Wisconsin

NWS Milwaukee, WI issued this flash flood warning at Aug 20, 2018, 5:32 PM CDT for Dane County, Wisconsin. It was in force for 3 hr. 4 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 20, 2018, 5:32 PM CDT (22:32 UTC)
Expired
Aug 20, 2018, 8:30 PM CDT
In force
3 hr
Issued by
NWS Milwaukee, WI
Area
Storm-based polygon
Flood severity
None

County Dane County, WI

The radar

The Milwaukee radar (KMKX), 78 km from the middle of the area, began a volume at 22:35 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

TimeReportWhereRemark
Aug 20, 5:49 PM CDTHEAVY RAIN 4.823 Ne Verona, WI
Aug 20, 6:05 PM CDTFLASH FLOOD3 Ssw Middleton, WIWATER RESCUE AT THE INTERSECTION OF MINERAL POINT RD AND COMMERCE DR.
Aug 20, 6:32 PM CDTFLASH FLOOD1 Wnw Middleton, WIIMPASSABLE ROADS WITH CARS STRANDED.
Aug 20, 8:05 PM CDTHEAVY RAIN 9.15 Wnw Verona, WI

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

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.5 hours before the alert went out and 181 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 12:00Z on 2018-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 224 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 12:00Z on 2018-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 94 square meters per square second.19395878Sfc1 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
224 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
765 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
73 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted.

879 
WGUS53 KMKX 202232
FFWMKX
WIC025-210130-
/O.NEW.KMKX.FF.W.0005.180820T2232Z-180821T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Milwaukee/Sullivan WI
532 PM CDT MON AUG 20 2018

The National Weather Service in Milwaukee/Sullivan has issued a

* Flash Flood Warning for...
  Western Dane County in south central Wisconsin...

* Until 830 PM CDT.

* At 529 PM CDT, local law enforcement reported water over a foot 
  deep in a street, vehicles stuck in a parking lot, and vehicles 
  stuck in a flooded intersection on the west side of Madison. One 
  to two inches of rain have already fallen in the past hour. Flash 
  flooding is already occurring.

* Some locations that will experience flooding include...
  Madison, Fitchburg, Middleton, Waunakee, Verona, Oregon, Mount
  Horeb, Cross Plains, Belleville, Shorewood Hills, Maple Bluff, Camp
  Randall Stadium, Paoli, Pine Bluff, Mount Vernon, Henry Vilas Zoo,
  Marxville and UW-Madison.

Additional rainfall amounts of one to two inches are possible in 
the next hour in the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

&&

LAT...LON 4321 8937 4287 8933 4287 8971 4322 8973

$$

WOOD
3 follow-up statements
599 
WGUS73 KMKX 202314
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
614 PM CDT MON AUG 20 2018

WIC025-210130-
/O.CON.KMKX.FF.W.0005.000000T0000Z-180821T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Dane WI-
614 PM CDT MON AUG 20 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
WESTERN DANE COUNTY...

At 608 PM CDT, local law enforcement reported flash flooding on the 
west side of Madison. A water rescue was reported at the 
intersection of Commerce Street and Mineral Point Road. There are 
several roads and intersections that are flooded with some stranded 
vehicles on the west side of Madison. Anywhere from two to four 
inches of rain have fallen in this area, with locally higher 
amounts. Flash flooding is already occurring.

Some locations that will experience flooding include...
Madison, Fitchburg, Middleton, Waunakee, Verona, Oregon, Mount Horeb,
Cross Plains, Belleville, Shorewood Hills, Maple Bluff, Camp Randall
Stadium, Paoli, Pine Bluff, Mount Vernon, Henry Vilas Zoo, Marxville
and UW-Madison.

Additional rainfall amounts of one to two inches are possible in 
the next hour or two in the warned area. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

&&

LAT...LON 4321 8937 4287 8933 4287 8971 4322 8973

$$

WOOD
089 
WGUS73 KMKX 210009
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
709 PM CDT MON AUG 20 2018

WIC025-210130-
/O.CON.KMKX.FF.W.0005.000000T0000Z-180821T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Dane WI-
709 PM CDT MON AUG 20 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
WESTERN DANE COUNTY...

At 701 PM CDT, local law enforcement reported flash flooding on the 
west side of Madison, as well as the Middleton area. At 632 PM CDT, 
a spotter reported impassable roads with vehicles stranded on the 
west northwest side of Middleton. Several reports of flooded roads 
and intersections, with some vehicles stranded, have occurred on the 
west side of Madison over the past hour and a half. 

Two to five inches of rain have fallen, with the highest amounts 
estimated from radar over the west side of Madison and toward the 
Middleton area. Flash flooding is already occurring.

Some locations that will experience flooding include...
Madison, Fitchburg, Middleton, Waunakee, Verona, Oregon, Mount Horeb,
Cross Plains, Belleville, Shorewood Hills, Maple Bluff, Camp Randall
Stadium, Paoli, Pine Bluff, Mount Vernon, Henry Vilas Zoo, Marxville
and UW-Madison.

Additional rainfall amounts of one to two inches are possible in the 
next hour or two in the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

&&

LAT...LON 4321 8937 4287 8933 4287 8971 4322 8973

$$

WOOD
449 
WGUS73 KMKX 210101
FFSMKX

Flash Flood Statement
National Weather Service Milwaukee/Sullivan WI
801 PM CDT MON AUG 20 2018

WIC025-210130-
/O.CON.KMKX.FF.W.0005.000000T0000Z-180821T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Dane WI-
801 PM CDT MON AUG 20 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
WESTERN DANE COUNTY...

At 755 PM CDT, local law enforcement reported flash flooding on the 
west side of Madison, as well as in the Middleton and Cross Plains 
areas. Four to seven inches of rain have generally fallen across the 
west side of Madison, as well as Cross Plains, Middleton, Mount 
Horeb and areas west of Verona. 

There are several reports of flooded roads and intersections, with 
stranded vehicles, on the west side of Madison, Middleton and Cross 
Plains areas. Flash flooding is already occurring.

Some locations that will experience flooding include...
Madison, Fitchburg, Middleton, Waunakee, Verona, Oregon, Mount Horeb,
Cross Plains, Belleville, Shorewood Hills, Maple Bluff, Camp Randall
Stadium, Paoli, Pine Bluff, Mount Vernon, Henry Vilas Zoo, Marxville
and UW-Madison.

Additional rainfall amounts of two to four inches are possible in 
the warned area over the next few hours. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

&&

LAT...LON 4321 8937 4287 8933 4287 8971 4322 8973

$$

WOOD

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 8:43 PM CDTSmall Craft AdvisoryMKX61 hr
Aug 20, 3:36 PM CDTAreal Flood AdvisoryMKXDane114 min
Aug 20, 6:52 PM CDTAreal Flood AdvisoryMKXDane, Iowa, Sauk3 hr

Nearby

Flash Flood Warnings in Wisconsin, 2018Every flash flood warning in 2018

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.