Alert archive / Iowa / Flash Flood Warnings in 2001

Flash Flood Warning 7, NWS Des Moines, IA

May 2, 2001Calhoun County, Sac County, Iowa

NWS Des Moines, IA issued this flash flood warning at May 2, 2001, 1:50 AM CDT for Calhoun County, Sac 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 the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: May 2, 2001, 1:50 AM CDT (06:50 UTC)
Expired: May 2, 2001, 4:45 AM CDT
In force: 3 hr
Issued by: NWS Des Moines, IA
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Calhoun County, IA, Sac County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 6.8 hours before the alert went out and 167 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1236 J/kg
Mixed-layer CIN: -26 J/kg
Mixed-layer LCL: 2701 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 37 m²/s²
0-3 km storm-relative helicity: 142 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 6.8

Open this sounding in Storm Lab

The text

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

000 
WGUS53 KDMX 020656
FFWDSM
IAC025-161-020950-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
150 AM CDT WED MAY 2 2001

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CALHOUN COUNTY IN WEST CENTRAL IOWA
  SAC COUNTY IN WEST CENTRAL IOWA

* UNTIL 445 AM CDT

* AT 147 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH FLASH FLOOD PRODUCING RAINS OVER ODEBOLT...OR
  ABOUT 54 MILES WEST OF FORT DODGE...MOVING EAST AT 15 MPH.

* THUNDERSTORMS WITH HEAVY RAIN WILL CONTINUE TO TRAIN ACROSS SAC
  AND CALHOUN COUNTIES FOR THE NEXT SEVERAL HOURS.  2 TO 4 INCHES OF
  RAIN HAS ALREADY OCCURRED WITH AN ADDITIONAL 1 TO 3 INCHES OF RAIN
  POSSIBLE.  TOTAL AMOUNTS OF RAIN WILL RANGE FROM 3 TO 6 INCHES WITH
  ISOLATED HIGHER AMOUNTS.  CITIES INCLUDED IN THE WARNING ARE LAKE
  VIEW...WALL LAKE...SAC CITY...LYTTON...ROCKWELL CITY AND JOLLEY.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. DO NOT DRIVE INTO WATER OF
UNKNOWN DEPTH...THE ROAD MAYBE WASHED OUT.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA...LIVING NEAR THE AFFECTED
WATERWAYS...YOU SHOULD TAKE IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND
PROPERTY.

LAT...LON 4254 9538 4222 9529 4223 9442 4254 9447

$$
COGIL

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 1, 7:35 PM CDT	Tornado Warning	DMX	Carroll, Greene, Guthrie	30 min
May 1, 8:04 PM CDT	Tornado Warning	DMX	Guthrie	31 min
May 1, 8:48 PM CDT	Severe Thunderstorm Warning	DMX	Crawford	42 min
May 1, 9:25 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	40 min
May 1, 9:38 PM CDT	Severe Thunderstorm Warning	DMX	Crawford	32 min
May 1, 10:04 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	26 min
May 1, 10:44 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun	41 min
May 1, 10:48 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	32 min

Nearby

Flash Flood Warnings in Iowa, 2001 Every flash flood warning in 2001

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.