Alert archive / Iowa / Flash Flood Warnings in 1996

Flash Flood Warning 15, NWS Des Moines, IA

July 17, 1996Carroll County, Crawford County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jul 17, 1996, 6:04 AM CDT for Carroll County, Crawford 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
Jul 17, 1996, 6:04 AM CDT (11:04 UTC)
Expired
Jul 17, 1996, 10:00 AM CDT
In force
4 hr
Issued by
NWS Des Moines, IA
Area
Whole counties

Counties Carroll County, IA, Crawford County, IA

The radar

The Des Moines radar (KDMX), 121 km from the middle of the area, began a volume at 11:06 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, 11.1 hours before the alert went out and 131 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 1996-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1921 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 1996-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 101 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
1921 J/kg
Mixed-layer CIN
-74 J/kg
Mixed-layer LCL
979 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
101 m²/s²
0-3 km storm-relative helicity
214 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 171107
FFWDSM
IAC027-047-171500-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
604 AM CDT WED JUL 17 1996

* FLASH FLOOD WARNING FOR
  CARROLL COUNTY - WEST CENTRAL IOWA
  CRAWFORD COUNTY - WEST CENTRAL IOWA

* UNTIL 1000 AM CDT
 
* SOME STREAMS AFFECTED
    WILLOW
    BOYER
    EAST BOYER
    SOLDIER
    BRUSHY CREEK
    ALL RACCOON RIVER BASINS
    UPPER REACHES OF THE NISHNABOTNA

* CAUSE AND EFFECT
THUNDERSTORMS HAVE PRODUCED WIDEPSREAD RAINFALL AMOUNTS OF 5 TO 6
INCHES WITH ISOLATED AMOUNTS UP TO 10 INCHES OVERNIGHT.  STREET
FLOODING HAS BEEN REPORTED IN MANY AREAS WITH NUMEROUS ROAD
CLOSINGS.  THE BOYER RIVER IN DENISON HAS REACHED BANKFUL
PROMPTING EVACUATIONS IN THE CITY.

* FORECAST CONDITIONS
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE OVER THE AREA
THROUGH MID-MORNING.  UP TO AN ADDITIONAL INCH OF RAIN IS
POSSIBLE.

THIS WARNING EXTENDS THE WARNINGS ALREADY IN EFFECT FO6R CRAWFORD AND
CARROLL COUNTIES.

LEAVE FLOOD PRONE OR LOW LYING AREAS IMMEDIATELY.  DO NOT DRIVE INTO
STANDING WATER.  6 TO 8 INCHES OF WATER IS ENOUGH TO MOVE A CAR.

KUBINA

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 8:14 PM CDTSevere Thunderstorm WarningDMXCrawford31 min
Jul 16, 10:46 PM CDTSevere Thunderstorm WarningDMXCrawford34 min
Jul 17, 12:46 AM CDTFlash Flood WarningDMXCrawford6 hr
Jul 17, 1:12 AM CDTSevere Thunderstorm WarningDMXGreene33 min
Jul 17, 2:36 AM CDTFlash Flood WarningDMXCarroll6 hr

Nearby

Flash Flood Warnings in Iowa, 1996Every flash flood warning in 1996

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.