Alert archive / Iowa / Flash Flood Warnings in 1990

Flash Flood Warning 2, NWS Sioux Falls, SD

May 19, 1990Woodbury County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at May 19, 1990, 1:07 AM CDT for Woodbury County, Iowa. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
May 19, 1990, 1:07 AM CDT (06:07 UTC)
Expired
May 19, 1990, 5:15 AM CDT
In force
4 hr
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Woodbury County, IA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 6.1 hours before the alert went out and 122 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, Omaha, NE at 00:00Z on 1990-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Omaha, NE at 00:00Z on 1990-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 218 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3572 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
218 m²/s²
0-3 km storm-relative helicity
319 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSUX 190607
FFWSUX
IAC193-191015-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
FLASH FLOOD WARNING 
NATIONAL WEATHER SERVICE SIOUX CITY IA
107 AM CDT SAT MAY 19 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING 
EFFECTIVE UNTIL 515 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTY

   IN THE WEST CENTRAL PART OF IOWA
      WESTERN WOODBURY

A FLASH FLOOD WARNING MEANS FLOODING IS OCCURRING OR IMMINENT.

THUNDERSTORMS WITH HEAVY RAIN WERE OVER PLYMOUTH AND WOODBURY
COUNTIES FROM 30 MILES NORTHEAST OF SIOUX CITY TO 20 MILES
SOUTHEAST OF SIOUX CITY. HEAVY PRECIPITATION WAS EXPECTED TO
CONTINUE OVER THE HEADWATERS OF PERRY CREEK...THE FLOYD RIVER AND
THE WEST FORK OF THE LITTLE SIOUX RIVER. THIS PRECIPITATION WILL
CAUSE EXTENSIVE DOWNSTREAM FLOODING IN WESTERN WOODBURY COUNTY
AND SIOUX CITY.

MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. VEHICLES CAUGHT IN
RISING WATERS SHOULD BE ABANDONED. DO NOT ATTEMPT TO CROSS BRIDGES
OR LOW SPOTS IF WATER COVERS THEM. NEVER TRY TO CROSS A FLOWING
STREAM...EVEN A SMALL ONE...ON FOOT. ACT QUICKLY. MOVE TO HIGHER
GROUND TO ESCAPE RISING WATER.

KROPP

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 19, 5:30 AM CDTFlash Flood WarningFSDWoodbury2 hr

Nearby

Flash Flood Warnings in Iowa, 1990Every flash flood warning in 1990

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.