Alert archive / Iowa / Flash Flood Warnings in 2002

Flash Flood Warning 20, NWS Sioux Falls, SD

May 29, 2002Plymouth County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at May 29, 2002, 1:12 AM CDT for Plymouth County, Iowa. It was in force for 93 min. 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 29, 2002, 1:12 AM CDT (06:12 UTC)
Expired
May 29, 2002, 2:45 AM CDT
In force
93 min
Issued by
NWS Sioux Falls, SD
Area
Counties, with a storm outline in the text

County Plymouth County, IA

The radar

The Sioux Falls radar (KFSD), 100 km from the middle of the area, began a volume at 06:15 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

Omaha, NE (KOAX), launched 00:00Z, 6.2 hours before the alert went out and 156 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 2002-05-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2280 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, Omaha, NE at 00:00Z on 2002-05-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
2280 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1163 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
118 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 
WGUS53 KFSD 290615
FFWFSD
IAC149-290745-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
112 AM CDT WED MAY 29 2002

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  PLYMOUTH COUNTY IN NORTHWEST IOWA

* UNTIL 245 AM CDT

* AT 112 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
VERY HEAVY RAINFALL WITH THUNDERSTORMS WAS OCCURRING OVER 
SOUTHWESTERN PLYMOUTH COUNTY NORTH OF SIOUX CITY.  RADAR ESTIMATES 
THAT THREE TO FOUR INCHES OF RAIN HAVE ALREADY OCCURED.  WITH 
THUNDERSTORMS EXPECTED TO CONTINUE THROUGH 2 AM...ANOTHER INCH OF 
RAIN POSSIBLE OVER THIS AREA.   

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.


LAT...LON 4285 9650 4259 9648 4261 9632 4269 9632

The office that day

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

IssuedProductOfficeCountiesLasted
May 29, 12:55 AM CDTFlash Flood WarningFSDWoodbury20 min
May 29, 12:55 AM CDTFlash Flood WarningFSDWoodbury95 min
May 29, 2:25 AM CDTFlash Flood WarningFSDWoodbury3 hr
May 29, 2:41 AM CDTFlash Flood WarningFSDPlymouth3 hr

Nearby

Flash Flood Warnings in Iowa, 2002Every flash flood warning in 2002

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.