Alert archive / Iowa / Flash Flood Warnings in 1998

Flash Flood Warning 21, NWS Des Moines, IA

June 23, 1998Calhoun County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jun 23, 1998, 11:53 PM CDT for Calhoun County, Iowa. It was in force for 4 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
Jun 23, 1998, 11:53 PM CDT (04:53 UTC)
Expired
Jun 24, 1998, 3:50 AM CDT
In force
4 hr
Issued by
NWS Des Moines, IA
Area
Whole counties

County Calhoun County, IA

The radar

The Des Moines radar (KDMX), 105 km from the middle of the area, began a volume at 04:55 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, 4.9 hours before the alert went out and 287 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 1998-06-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 901 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, Minneapolis, MN at 00:00Z on 1998-06-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 212 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
901 J/kg
Mixed-layer CIN
-26 J/kg
Mixed-layer LCL
1105 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
212 m²/s²
0-3 km storm-relative helicity
335 m²/s²
Significant tornado parameter
1.4
Supercell composite
8.6

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 240453
FFWDSM
IAC025-240850-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1153 PM CDT TUE JUN 23 1998

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

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

* UNTIL 350 AM CDT

* AT 1150 PM CDT... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A THUNDERSTORM WITH VERY HEAVY RAIN OVER CALHOUN COUNTY...MOVING
  EAST AT 15 MPH.

* DOPPLER RADAR ESTIMATES THAT 2 TO 3 INCHES OF RAINFALL HAS FALLEN
  OVER CALHOUN COUNTY.  IN ADDITION...THUNDERSTORMS WILL CONTINUE TO
  MOVE OVER CALHOUN COUNTY FOR THE NEXT COUPLE OF HOURS PRODUCING
  RAINFALL RATES OF 1 TO 2 INCHES AN HOUR.  THIS WILL CAUSE FLASH
  FLOODING ALONG CREEKS AND STREAMS AS WELL AS IN URBAN AREAS.

SOME STREAMS AFFECTED INCLUDE...
  CEDAR CREEK...PURGATORY CREEK...CAMP CREEK AND LAKE CREEK.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGER OF FLOODING.

COGIL

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 23, 8:59 PM CDTSevere Thunderstorm WarningDMXSac46 min
Jun 23, 9:25 PM CDTSevere Thunderstorm WarningDMXCrawford30 min
Jun 23, 9:47 PM CDTTornado WarningDMXSac33 min
Jun 23, 9:52 PM CDTTornado WarningDMXCalhoun33 min
Jun 23, 10:08 PM CDTSevere Thunderstorm WarningDMXCalhoun, Carroll47 min
Jun 23, 10:17 PM CDTSevere Thunderstorm WarningDMXWebster33 min
Jun 23, 10:19 PM CDTFlash Flood WarningDMXPalo Alto3 hr
Jun 23, 10:38 PM CDTSevere Thunderstorm WarningDMXHumboldt32 min
Jun 23, 10:41 PM CDTFlash Flood WarningDMXKossuth4 hr
Jun 23, 10:41 PM CDTFlash Flood WarningDMXSac4 hr
Jun 23, 10:54 PM CDTFlash Flood WarningDMXPocahontas4 hr
Jun 23, 11:20 PM CDTFlash Flood WarningDMXCrawford4 hr
Jun 23, 11:31 PM CDTFlash Flood WarningDMXWinnebago4 hr
Jun 23, 11:34 PM CDTSevere Thunderstorm WarningDMXCerro Gordo, Franklin, Worth31 min
Jun 23, 11:56 PM CDTSevere Thunderstorm WarningDMXButler34 min
Jun 24, 12:34 AM CDTFlash Flood WarningDMXHamilton, Webster4 hr
Jun 24, 2:35 AM CDTFlash Flood WarningDMXSac4 hr
Jun 24, 2:50 AM CDTFlash Flood WarningDMXCrawford4 hr

Nearby

Flash Flood Warnings in Iowa, 1998Every flash flood warning in 1998

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.