Alert archive / Iowa / Flash Flood Warnings in 1998

Flash Flood Warning 26, NWS Des Moines, IA

July 5, 1998Cass County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jul 5, 1998, 8:54 AM CDT for Cass 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 5, 1998, 8:54 AM CDT (13:54 UTC)
Expired
Jul 5, 1998, 11:50 AM CDT
In force
3 hr
Issued by
NWS Des Moines, IA
Area
Whole counties

County Cass County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 1.9 hours before the alert went out and 120 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 12:00Z on 1998-07-05Temperature 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 12:00Z on 1998-07-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -62 square meters per square second.193958Sfc1 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
960 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-62 m²/s²
0-3 km storm-relative helicity
261 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 051354
FFWDSM
IAC029-051650-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
854 AM CDT SUN JUL 5 1998

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CASS COUNTY IN SOUTHWESTERN IOWA

* UNTIL 1150 AM CDT

* AT 800 AM CDT... REPORTS INDICATED A THUNDERSTORM WITH
VERY HEAVY RAINS MOVING THROUGH WEST CENTRAL IOWA ... MOVING EAST AT
10 TO 15 MPH.

* HEAVY RAINS...TWO INCHES SINCE 800 AM...WITH TOTALS AROUND THREE
  INCH HAVE BEEN REPORTED IN ATLANTIC BY THE RADIO STATION.
  THESE HEAVY RAINS WILL PRODUCE FLOODING IN THE COUNTY OF SMALL
  STREAMS AND CREEKS.   THE WILL BE A SLOWER REACTION ON THE EAST
  NISHNABTONA RIVER.

SOME STREAMS AFFECTED INCLUDE...
  TURKEY CREEK
  TROUBLESOME CREEK
  SPRING CREEK
  CROOKED CREEK

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

FORSTER

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Jul 5, 5:44 AM CDT, 3 hours 10 minutes before
IAZ070-071-081>085-092>096-061100-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
544 AM CDT SUN JUL 5 1998

HAZARD--CLUSTERS OF NON-SEVERE THUNDERSTORMS PRODUCING HEAVY RAIN.

AREA OF CONCERN AND TIMING DETAILS--WEST OF I-35 TODAY AND ENTIRE
AREA OF RESPONSIBILITY TONIGHT.

METEOROLOGICAL COMMENTS--A STATIONARY FRONT LOCATED ALONG THE
KANSAS/NEBRASKA BORDER INTO NORTHERN MISSOURI WILL PROVIDE A
FOCUSING MECHANISM FOR THUNDERSTORMS IN EASTERN NEBRASKA...WHICH ARE
MOVING INTO WESTERN IOWA. MOVEMENT OF THE THUNDERSTORMS IS LESS THAN
20 MPH WITH STORMS TRAILING AFTER EACH OTHER. RAINFALL AMOUNTS AROUND
1 INCH PER HOUR ARE LIKELY...A FEW MAY PRODUCE 1-2 INCH RAINS PER
HOUR. THE AREA OF STORMS IN WESTERN IOWA SHOULD SHRINK AFTER 8 OR 9
AM WITH NEW DEVELOPMENT EXPECTED NEAR THE MISSOURI RIVER LATER TODAY.
A LARGE THUNDERSTORM COMPLEX IS THEN EXPECTED IN IOWA TONIGHT WITH
ADDITIONAL RAINS.

PRECAUTIONS--PERSO\NS WITH INTERESTS ON SMALL STREAMS AND FLOOD-PRONE
AREAS SHOULD STAY ALERT TO THE LATEST FORECASTS CONCERNING HEAVY
RAINFALL.

MYERS
Special weather statement, Jul 5, 5:44 AM CDT, 3 hours 10 minutes before
IAZ070-071-081>085-092>096-061100-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
544 AM CDT SUN JUL 5 1998

HAZARD--CLUSTERS OF NON-SEVERE THUNDERSTORMS PRODUCING HEAVY RAIN.

AREA OF CONCERN AND TIMING DETAILS--WEST OF I-35 TODAY AND ENTIRE
AREA OF RESPONSIBILITY TONIGHT.

METEOROLOGICAL COMMENTS--A STATIONARY FRONT LOCATED ALONG THE
KANSAS/NEBRASKA BORDER INTO NORTHERN MISSOURI WILL PROVIDE A
FOCUSING MECHANISM FOR THUNDERSTORMS IN EASTERN NEBRASKA...WHICH ARE
MOVING INTO WESTERN IOWA. MOVEMENT OF THE THUNDERSTORMS IS LESS THAN
20 MPH WITH STORMS TRAILING AFTER EACH OTHER. RAINFALL AMOUNTS AROUND
1 INCH PER HOUR ARE LIKELY...A FEW MAY PRODUCE 1-2 INCH RAINS PER
HOUR. THE AREA OF STORMS IN WESTERN IOWA SHOULD SHRINK AFTER 8 OR 9
AM WITH NEW DEVELOPMENT EXPECTED NEAR THE MISSOURI RIVER LATER TODAY.
A LARGE THUNDERSTORM COMPLEX IS THEN EXPECTED IN IOWA TONIGHT WITH
ADDITIONAL RAINS.

PRECAUTIONS--PERSO\NS WITH INTERESTS ON SMALL STREAMS AND FLOOD-PRONE
AREAS SHOULD STAY ALERT TO THE LATEST FORECASTS CONCERNING HEAVY
RAINFALL.

MYERS

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.