Alert archive / Iowa / Flash Flood Warnings in 1999

Flash Flood Warning 2, NWS La Crosse, WI

July 18, 1999Chickasaw County, Iowa

NWS La Crosse, WI issued this flash flood warning at Jul 18, 1999, 11:49 PM CDT for Chickasaw 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 counties it named.

The facts

Issued
Jul 18, 1999, 11:49 PM CDT (04:49 UTC)
Expired
Jul 19, 1999, 2:50 AM CDT
In force
3 hr
Issued by
NWS La Crosse, WI
Area
Whole counties

County Chickasaw County, IA

The radar

The La Crosse radar (KARX), 124 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.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 4.8 hours before the alert went out and 219 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 00:00Z on 1999-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 934 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 1999-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 square meters per square second.1939Sfc1 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
934 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
1378 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
120 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KLSE 190450
FFWLSE
IAC037-190750-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LA CROSSE WI
1149 PM CDT SUN JUL 18 1999

THE NATIONAL WEATHER SERVICE IN LA CROSSE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CHICKASAW COUNTY IN NORTHEASTERN IOWA

* UNTIL 250 AM CDT

* AT 1145 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM WITH VERY HEAVY RAIN 20 MILES SOUTHWEST OF DECORAH...
  NEAR NEW HAMPTON... MOVING SLOWLY EAST. ADDITIONAL THUNDERSTORMS
  WERE REDEVELOPING FARTHER WEST ACROSS NORTH CENTRAL IOWA.

* RADAR ESTIMATES OF UP TO 2 INCHES OF RAIN HAS FALLEN ACROSS
  CHICKASAW COUNTY AND  LAW ENFORECEMENT OFFICIALS REPORT MANY
  DITCHES IN RURAL AREAS ALREADY FULL WITH SOME STREET FLOODING IN
  NEW HAMPTON..

DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD!

RABERDING


&

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 2:32 AM CDTFlash Flood WarningARXFloyd, Mitchell3 hr
Jul 19, 2:52 AM CDTFlash Flood WarningARXChickasaw3 hr
Jul 19, 5:31 AM CDTFlash Flood WarningARXFloyd, Mitchell3 hr
Jul 19, 9:49 AM CDTFlash Flood WarningARXFloyd, Mitchell6 hr

Nearby

Flash Flood Warnings in Iowa, 1999Every flash flood warning in 1999

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.