Alert archive / Iowa / Flash Flood Warnings in 2004

Flash Flood Warning 4, NWS La Crosse, WI

May 21, 2004Allamakee County, Winneshiek County, Iowa

NWS La Crosse, WI issued this flash flood warning at May 21, 2004, 7:41 PM CDT for Allamakee County, Winneshiek County, Iowa. 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
May 21, 2004, 7:41 PM CDT (00:41 UTC)
Expired
May 21, 2004, 10:45 PM CDT
In force
3 hr
Issued by
NWS La Crosse, WI
Area
Counties, with a storm outline in the text

Counties Allamakee County, IA, Winneshiek County, IA

The radar

The La Crosse radar (KARX), 76 km from the middle of the area, began a volume at 00:41 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

Minneapolis, MN (KMPX), launched 00:00Z, 0.7 hours before the alert went out and 232 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, Minneapolis, MN at 00:00Z on 2004-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 joules per kilogram.LCLEL10008507005003002001001 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, Minneapolis, MN at 00:00Z on 2004-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 215 square meters per square second.1939587897Sfc1 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
2 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
512 m above ground
0-6 km bulk shear
74 kt
0-1 km storm-relative helicity
215 m²/s²
0-3 km storm-relative helicity
257 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS53 KARX 220043
FFWARX
IAC005-191-220345-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LA CROSSE WI
741 PM CDT FRI MAY 21 2004

THE NATIONAL WEATHER SERVICE IN LA CROSSE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WINNESHIEK COUNTY IN NORTHEAST IOWA
  ALLAMAKEE COUNTY IN NORTHEAST IOWA

* UNTIL 1045 PM CDT

* AT 741 PM CDT...NATIONAL WEATHER SERVICE RADAR DETECTED
  THUNDERSTORMS PRODUCING VERY HEAVY RAIN EXTENDING FROM 13 MILES
  NORTHEAST OF NEW HAMPTON TO 14 MILES NORTH OF ELKADER. ESTIMATES   
  FROM RADAR INDICATED THAT NEARLY 1 INCH OF RAIN HAS FALLEN DURING  
  THE PAST HOUR JUST SOUTH OF THE WARNED AREA. THIS RAIN WILL        
  MOVE ACROSS THE AREA...AND THE ALREADY SATURATED GROUNDS. THE      
  STORMS PRODUCING THE VERY   HEAVY RAINFALL WERE MOVING NORTHEAST   
  AT 35 MPH.

* SOME LOCATIONS THAT MAY BE AFFECTED INCLUDE...CALMAR...DECORAH...
  SPILLVILLE...WAUKON...COUNTY ROADS A 26 AND X 6 A...COUNTY ROADS X
  16 AND W 48 AND STATE ROAD 76 AND COUNTY X 16.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IMMINENT.
IF YOU ARE IN THE WARNED AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO FORGE
FLOODED ROADWAYS BY FOOT OR AUTOMOBILE. IF YOUR VEHICLE STALLS...
ABANDON IT IMMEDIATELY AND SEEK HIGHER GROUND.

LAT...LON 4315 9204 4312 9136 4343 9129 4343 9188

$$

RIECK
1 follow-up statement
000 
WGUS73 KARX 220159
FFSARX
IAC005-191-220345-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
859 PM CDT FRI MAY 21 2004

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1045 PM CDT FOR
ALLAMAKEE AND WINNESHIEK COUNTIES...

AT 857 PM CDT...NATIONAL WEATHER SERVICE RADAR DETECTED THUNDERSTORMS
PRODUCING VERY HEAVY RAIN SOUTH OF A LANSING TO CALMAR LINE. ESTIMATES 
FROM RADAR INDICATED THAT NEARLY 1 INCH OF RAIN HAS FALLEN DURING 
THE PAST HOUR OVER THE WARNED AREA. THE STORMS PRODUCING THE VERY 
HEAVY RAINFALL WERE MOVING EAST AT 25 MPH.

SOME LOCATIONS THAT MAY BE AFFECTED INCLUDE...CALMAR...DECORAH...
OSSIAN AND SPILLVILLE.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IMMINENT.
IF YOU ARE IN THE WARNED AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO FORGE
FLOODED ROADWAYS BY FOOT OR AUTOMOBILE. IF YOUR VEHICLE STALLS...
ABANDON IT IMMEDIATELY AND SEEK HIGHER GROUND.

LAT...LON 4315 9204 4312 9136 4343 9129 4343 9188

$$

RABERDING

The office that day

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

IssuedProductOfficeCountiesLasted
May 21, 7:00 PM CDTFlash Flood WarningARXChickasaw, Floyd3 hr
May 21, 7:25 PM CDTSevere Thunderstorm WarningARXClayton35 min
May 21, 8:35 PM CDTFlash Flood WarningARXClayton, Fayette3 hr
May 21, 9:08 PM CDTFlash Flood WarningARXHoward, Mitchell3 hr
May 21, 9:09 PM CDTSevere Thunderstorm WarningARXClayton51 min
May 21, 9:57 PM CDTFlash Flood WarningARXChickasaw, Floyd3 hr
May 21, 10:45 PM CDTFlash Flood WarningARXAllamakee, Winneshiek3 hr
May 21, 11:28 PM CDTFlash Flood WarningARXClayton, Fayette3 hr
May 22, 12:11 AM CDTFlash Flood WarningARXHoward, Mitchell3 hr
May 22, 12:18 AM CDTSevere Thunderstorm WarningARXFloyd57 min
May 22, 12:59 AM CDTFlash Flood WarningARXChickasaw, Floyd3 hr
May 22, 2:07 AM CDTSevere Thunderstorm WarningARXFayette38 min
May 22, 2:16 AM CDTSevere Thunderstorm WarningARXClayton44 min

Nearby

Flash Flood Warnings in Iowa, 2004Every flash flood warning in 2004

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.