Alert archive / Iowa / Flash Flood Warnings in 1986

Flash Flood Warning 3, NWS Des Moines, IA

June 30, 1986Polk County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jun 30, 1986, 3:45 AM CDT for Polk County, Iowa. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Jun 30, 1986, 3:45 AM CDT (08:45 UTC)
Expired
Jun 30, 1986, 9:45 AM CDT
In force
6 hr
Issued by
NWS Des Moines, IA
Area
Whole counties

County Polk County, IA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 8.8 hours before the alert went out and 236 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 1986-06-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 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 1986-06-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 119 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3623 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
119 m²/s²
0-3 km storm-relative helicity
262 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 300846
FFWDSM
IAC153-301445-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
345 AM CDT MON JUN 30 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING
EFFECTIVE UNTIL 945 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF

CENTRAL IOWA...POLK

A FLASH FLOOD WARNING MEANS FLOODING IS IMMINENT OR IS OCCURRING.
TAKE NECESSARY PRECAUTIONS IMMEDIATELY.

THIS FLASH FLOOD WARNING CONCERNS FOUR MILE CREEK IN THE DES
MOINES AREA.

HEAVY RAINS OF LAST NIGHT HAVE CAUSED SIGNIFICANT RISES ON
FOUR MILE CREEK.  AT 345 AM CDT THE STAGE WAS 11 FEET.  FLOOD
STAGE IS 12 FEET.  THE CREEK SHOULD CONTINUE TO RISE AND BE
AT OR SLIGHTLY ABOVE FLOOD STAGE THROUGH EARLY MORNING HOURS...
OR UNTIL 8 OR 9 AM CDT.

PEOPLE LIVING IN FLOOD PRONE AREAS SHOULD MOVE TO HIGHER GROUND
AT ONCE.  ACT QUICKLY..AS FLOOD WATERS OFTEN RISE VERY QUICKLY.

ELLINGSON

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 30, 12:17 AM CDT, 3 hours 28 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1215 AM CDT MON JUN 30 1986

...SEVERE THUNDERSTORM WATCH IN EFFECT FOR A LARGE PART OF
SOUTHERN AND CENTRAL IOWA UNTIL 5 AM MONDAY MORNING...

AT 1210 AM...STRONG THUNDERSTORMS WERE OVER EAST CENTRAL..CENTRAL
AND SOUTH CENTRAL IOWA.  ONE GROUP OF STORMS WERE NEAR IOWA CITY.
OTHER STORMS WERE NEAR NEWTON..OSCEOLA AND ALSO WEST OF LAMONI
NEAR MT AYR.

VERY HEAVY RAINS..FREQUENT LIGHTNING AND WIND GUSTS BETWEEN 45 AND
50 MILES AN HOUR CAN BE EXPECTED WITH THESE STORMS.

AROUND OTHER PARTS OF IOWA..NUMEROUS SHOWERS AND SCATTERED THUNDER-
STORMS EXTENDED FROM EAST CENTRAL INTO SOUTHWEST IOWA.

THE SHOWERS AND STORmMS WERE MOVING SOUTHEAST AT 30 MILES AN HOUR.
{{}SIECZYNSKI
Special weather statement, Jun 30, 12:52 AM CDT, 2 hours 53 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1250 AM CDT MON JUN 30 1986

...SEVERE THUNDERSTORM WATCH IN EFFECT FOR A LARGE PART OF
SOUTHERN AND CENTRAL IOWA UNTIL 5 AM MONDAY MORNING...

AT 1235 AM...A NARROW BAND OF STRONG THUNDERSTORMS EXTENDED FROM
CENTRAL INTO SOUTH CENTRAL IOWA.  THE BAND WAS 10 MILES MILES WIDE
AND STRETCHED FROM NEAR MARSHALLTOWN THROUGH PELLA AND KNOXVILLE
TO JUST EAST OF LAMONI.  OTHER STORNG STORMS WERE NEAR BELLE PLAINE
AND MARENGO..ABOUT 25 MILES WEST OF CEDAR RAPIDS.

VERY HEAVY RAINS..FREQUENT DANGEROUS LIGHTNING AND BRIEF WIND GUSTS
OF 45 TO 50 MILES AN HOUR WILL BE EXPERIENCED WITH THE PASSAGE
OF THESE STORMS.

AROUND OTtHER PARTS OF IOWA..NUMEROUS SHOWERS AND SCATTERED THUNDER-
STORMS WERE OVER ALL BUT THE NORTHWESTERN COUNTIES.

THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 30 MILES AN HOUR.

SIECZYNSKI
Special weather statement, Jun 30, 1:55 AM CDT, 1 hour 50 minutes before
<PQ<
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
150 AM CDT MON JUN 30 1986

THE SEVERE THUNDERSTORM WATCH HAS BEEN DISCONTINUED FOR PARTS OF
CENTRAL..SOUTH CENTRAL..AND SOUTHWEST IOWA.  THE HEAVIER STORMS
HAVE MOVED ON TO THE EAST OF THAT AREA AND SEVERE WEATHER NO LONGER
APPEARS LIKELY.

THE CLEARED COUNTIES ARE...

...NORTH CENTRAL...

BUTLER

...NORTHEAST...
BLACK HAWK      BREMER          BUCHANAN        FAYETTE

...CENTRAL...
BOONE           DALLAS          GRUNDY          JASPER
MARSHALL        POLK            STORY

...SOUTHWEST...
ADAMS           FREMONT         MONTGOMERY      PAGE
TAYLOR

...SOUTH CENTRAL...
CLARKE          DECATUR         LUCAS           MADISON
MARION          RINGGOLD        UNION           WARREN
WAYNE

SOME CITIES INCLUDED IN THE CLEARED AREA ARE...

AMES            BOONE           CRESTON         DES MOINES
INDEPENDENCE    INDIANOLA       KNOXVILLE       MARSHALLTOWN
NEWTON          OELWEIN         PERRY           RED OAK
SHENANDOAH      WATERLOO        WAVERLY

HOWEVER....THE WATCH REMAINS IN EFFECT FOR PARTS OF EAST CENTRAL
AND SOUTHEAST IOWA UNTIL 5 AM.  PEOPLE IN THAT AREA SHOULD REMAIN
ON THE ALERT.

A FLASH FLOOD WATCH ALSO CONTINUES IN EFFECT FOR A LARGE PART OF
WESTERN AND CENTRAL IOWA FOR THE REMAINDER OF THE NIGHT.

ELLINGSON
Special weather statement, Jun 30, 2:19 AM CDT, 1 hour 26 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
215 AM CDT MON JUN 30 1986

...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR A LARGE
PART OF EASTERN IOWA UNTIL 5 AM THIS MORNING...

NO SEVERE WEATHER WAS REPORTED IN IOWA BETWEEN 130-215 AM.

AT 210 AM..STRONG THUNDERSTORMS CONTINUED IN EAST CENTRAL AND SOUTH-
EAST IOWA NEAR BRIGHTON AND WASHINGTON..35 MILES NORTHWEST OF OF
BURLINGTON.

IN ADDITION TO VERY HEAVY RAINS..BRIEF GUSTY WINDS AND DANGEROUS
LIGHTNING CAN BE EXPECTED WITH THESE STORMS.

ELSEWHERE..NUMEROUS SHOWERS ANS SCATTERED THUNDERSHOWERS WERE OVER ALL
BUT THE NORTHWEST THIRD OF THER STATE.

THE SHOWERS AND STORMS WERE MOVING EAST AT 35 MILES AN HOUR WITH A
SLIGHT DECREASE IN INTENSITY SINCE 130 AM.

SIECZYNSKI
Special weather statement, Jun 30, 2:36 AM CDT, 1 hour 9 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
235 AM CDT MON JUN 30 1986

...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR A LARGE
PART OF EASTERN IOWA UNTIL 5 AM THIS MORNING...

NO SEVERE WEATHER WAS REPORTED IN IOWA BETWEEN 130-235 AM.

AT 225 AM..ISOLATED STRONG THUNDERSTORMS LINGERED IN EAST CENTRAL AND
SOUTHEAST IOWA.  ONE STORM WAS JUST WEST OF MORNING SUN..45 MILES
SOUTHWEST OF THE QUAD CITIES.  ANOTHER STORM WAS BETWEEN FORT MADISON
AND FARMINGTON..20 MILES SOUTHWEST OF BURLINGTON.

IN ADDITION TO VERY HEAVY RAINS..BRIEF GUSTY WINDS AND DANGEROUS
LIGHTNING CAN BE EXPECTED WITH THESE STORMS.

ELSEWHERE..NUMEROUS SHOWERS AND SCATTERED THUNDERSHOWERS WERE OVER ALL
BUT THE NORTHWEST HALF OF THE STATE.  THE RAINFALL WAS ALONG AND SOUTH
OF A LINE FROM OMAHA/COUNCIL BLUFFS THROUGH DES MOINES TO WATERLOO.

THE SHOWERS AND STORMS WERE MOVING EAST AT 35 MILES AN HOUR WITH
A CONTINUED DECREASE IN INTENSITY.

SIECZYNSKI
Special weather statement, Jun 30, 3:45 AM CDT, 0 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
335 AM CDT MON JUN 30 1986

...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR EAST CENTRAL
AND SOUTHEAST IOWA UNTIL 5 AM THIS MORNING...

NO SEVERE WEATHER WAS REPORTED IN IOWA BETWEEN 230-335 AM.

AT 325 AM..AN ISOLATED THUNDERSTORM WAS INDICATED OVER EAST CENTRAL
IOWA 15 MILES SOUTHEAS OF CEDAR RAPIDS..BETWEEN IOWA CITY AND TIPTON.

NUMEROUS SHOWERS AND WIDELY SCATTERED THUNDERSHOWERS WERE OCCURRING
OVER MUCH OF THE SOUTHERN THIRD AND OVER THE EAST CENTRAL SECTION OF
THE STATE. THESE SHOWERS AND THUNDERSHOWERS WERE SOUTH AND EAST OF A
LINE FROM COUNCIL BLUFFS TO DES MOINES TO WATERLOO.

ALL OF THE PRECIPITATION WAS MOVING EAST AT 35 MILES AN HOUR.

FERRY

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 29, 7:30 PM CDTSevere Thunderstorm WarningDMXCalhoun45 min
Jun 29, 8:26 PM CDTSevere Thunderstorm WarningDMXGreene49 min
Jun 29, 9:00 PM CDTSevere Thunderstorm WarningDMXEmmet45 min
Jun 29, 10:00 PM CDTSevere Thunderstorm WarningDMXGuthrie40 min
Jun 29, 10:18 PM CDTSevere Thunderstorm WarningDMXCass42 min
Jun 29, 10:25 PM CDTFlash Flood WarningDMXDallas, Polk6 hr
Jun 29, 11:50 PM CDTTornado WarningDMXPolk25 min
Jun 30, 1:12 AM CDTSevere Thunderstorm WarningDMXIowa, Poweshiek48 min

Nearby

Flash Flood Warnings in Iowa, 1986Every flash flood warning in 1986

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.