Alert archive / Iowa / Flash Flood Warnings in 1996

Flash Flood Warning 2, NWS Des Moines, IA

June 16, 1996Story County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jun 16, 1996, 8:48 PM CDT for Story 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: Jun 16, 1996, 8:48 PM CDT (01:48 UTC)
Expired: Jun 16, 1996, 11:20 PM CDT
In force: 3 hr
Issued by: NWS Des Moines, IA
Area: Whole counties

County Story County, IA

The radar

The Des Moines radar (KDMX), 40 km from the middle of the area, began a volume at 01:51 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

Davenport, (KDVN), launched 00:00Z, 1.8 hours before the alert went out and 250 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: 955 J/kg
Mixed-layer CIN: -23 J/kg
Mixed-layer LCL: 1288 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 59 m²/s²
0-3 km storm-relative helicity: 114 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 170148
FFWDSM
IAC169-170415-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
848 PM CDT SUN JUN 16 1996

* FLASH FLOOD WARNING FOR
  NORTHWESTERN STORY COUNTY - CENTRAL IOWA

* UNTIL 1120 PM CDT
 
* SOME STREAMS AFFECTED
    KEIGLEY BRANCH
    SKUNK RIVER TRIBUTARIES
    BEAR CREEK

* CAUSE AND EFFECT
    UPWARDS OF THREE INCHES OF RAIN HAS FALLEN SINCE 600 PM OVER
    NORTHWEST STORY COUNTY BETWEEN STORY CITY...JEWELL AND NORTHERN
    BOONE COUNTY. FLOODING OF ROADWAYS...DITCHES AND SMALL STREAM IS
    OCCURRING OVER PORTIONS OF NORTHWESTERN STORY COUNTY.

* FORECAST CONDITIONS
    HEAVY RAINS WILL CONTINUE THROUGH 930 PM CDT PRODUCING ANOTHER
    INCH OF RAINFALL...WITH ADDITIONAL THUNDERSTORM DEVELOPMENT
    POSSIBLE.

LEAVE FLOOD PRONE OR LOW LYING AREAS IMMEDIATELY.

JUNGBLUTH

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, Jun 16, 3:16 PM CDT, 5 hours 32 minutes before

IAZ004>007-015>017-023>028-033>039-044>049-057>062-070>075-081>086-
092>097-170000-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
315 PM CDT SUN JUN 16 1996

HAZARD...THUNDERSTORMS WITH HEAVY RAINFALL OF 2 TO 3 INCHES AND
ISOLATED AMOUNTS UP TO 5 INCHES. THERE IS A SLIGHT CHANCE OF
THUNDERSTORMS PRODUCING HAIL UP TO DIME SIZE AND WIND GUSTS TO 60 MPH.

AREA OF CONCERN...THE THREAT OF BORDERLINE SEVERE THUNDERSTORMS IS
SOUTH OF HIGHWAY 30 AND WEST OF INTERSTATE 35. THE THREAT OF HEAVY
RAIN EXISTS OVER ALL OF CENTRAL IOWA.

TIMING DETAILS...THE BORDERLINE SEVERE WEATHER THREAT WILL LAST UNTIL
SUNSET...WITH THE HEAVY RAINFALL THREAT CONTINUING THROUGH EARLY MONDAY
MORNING.
                                                    .
METEOROLOGICAL COMMENTS...THE ATMOSPHERE WAS PRIMED FOR A SIGNIFICANT
RAINFALL EVENT. TROPICAL MOISTURE CONTINUED TO FEED INTO IOWA WITH
SURFACE DEWPOINTS IN THE LOWER 70S. THE ATMOSPHERE HAS ALSO
DESTABILIZED THIS AFTERNOON DUE TO A LITTLE SUNSHINE. A STATIONARY
FRONT WILL REMAIN IN PLACE NEAR HIGHWAY 20...WHILE A COLD FRONT
ADVANCES SLOWLY EAST ACROSS THE STATE. BOTH OF THESE BOUNDARIES WILL
FOCUS THUNDERSTORM DEVELOPMENT TONIGHT...WITH THE HEAVIEST RAIN
EXPECTED NEAR THE INTERSECTION OF THE TWO BOUNDARIES. A FEW STORMS IN
THE SOUTHWEST COULD BRIEFLY EXCEED SEVERE LEVELS WHERE INSTABILITY
WILL BE GREATEST THROUGH SUNSET. HOWEVER...THIS THREAT WILL END AS THE
STORMS CONSOLIDATE INTO A THUNDERSTORM COMPLEX. BECAUSE ALMOST THE
ENTIRE DEPTH OF THE ATMOSPHERE WILL BE SATURATED TONIGHT...THE RISK
FOR HEAVY RAIN WILL BE MUCH HIGHER THAN THE RISK OF SEVERE WEATHER.

PRECAUTIONS...FLASH FLOOD WATCHES HAVE BEEN EXPANDED TO INCLUDE MOST OF
THE STATE TONIGHT. THE HEAVY RAINS EARLIER TODAY HAVE SATURATED THE
GROUND...AND THE ADDITIONAL RAIN WILL MAINLY RUN OFF INTO STREAMS AND
RIVERS. WATER SYSTEMS WILL HAVE TO BE MONITORED CLOSELY TONIGHT. LOCAL
LAW ENFORCEMENT IS STRO NGLY ENCOURAGED TO RELAY ANY REPORTS OF FLOODED
CREEKS OR ROADS TONIGHT AS THE HEAVY RAINS MOVE IN.

PYTLAK

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 16, 8:21 PM CDT	Flash Flood Warning	DMX	Boone, Hamilton	3 hr
Jun 16, 9:47 PM CDT	Flash Flood Warning	DMX	Hardin	2 hr
Jun 16, 11:13 PM CDT	Flash Flood Warning	DMX	Fayette	3 hr
Jun 16, 11:14 PM CDT	Flash Flood Warning	DMX	Story	6 hr
Jun 16, 11:29 PM CDT	Flash Flood Warning	DMX	Hamilton, Hardin	2 hr
Jun 16, 11:29 PM CDT	Flash Flood Warning	DMX	Boone	2 hr

Nearby

Flash Flood Warnings in Iowa, 1996 Every 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.