Alert archive / Iowa / Flash Flood Warnings in 1990

Flash Flood Warning 26, NWS Des Moines, IA

July 20, 1990Decatur County, Ringgold County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jul 20, 1990, 1:36 AM CDT for Decatur County, Ringgold County, Iowa. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued: Jul 20, 1990, 1:36 AM CDT (06:36 UTC)
Expired: Jul 20, 1990, 6:30 AM CDT
In force: 5 hr
Issued by: NWS Des Moines, IA
Area: Whole counties

Counties Decatur County, IA, Ringgold 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, 6.6 hours before the alert went out and 208 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3623 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 32 m²/s²
0-3 km storm-relative helicity: 85 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 200636
FFWDSM
IAC053-159-201130-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
136 AM CDT FRI JUL 20 1990
 
THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  630 AM CDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN SOUTH CENTRAL IOWA
          ...DECATUR...RINGGOLD
 
AT 130 AM...DES MOINES RADAR INDICATED VERY HEAVY RAINS SCATTERED OVER
RINGGOLD AND DECATUR COUNTIES...OR 50 TO 75 MILES SOUTH AND SOUTHWEST
OF DES MOINES. MT. AYR IN RINGGOLD COUNTY HAS RECEIVED FIVE INCHES OF
RAIN SINCE 7 PM. VERY HEAVY RAINS OF ONE TO ONE AND ONE-HALF INCHES AN
HOUR WILL OCCUR OVER THE NEXT SEVERAL HOURS IN THE WARNING AREA.
 
SOME COMMUNITIES IN THE WARNING AREA ARE MT. AYR...BENTON...DELPHOS...
DIAGONAL...GRAND RIVER...DAVIS CITY...LEON AND LAMONI.
 
FLASH FLOODING OF SMALL STREAMS AND CREEKS WILL OCCUR THROUGH THE EARLYMORNING HOURS.  IF YOU LIVE IN A FLOOD PRONE AREA...MOVE TO HIGHER
GROUND OR AT LEAST CHECK YOUR PROPERTY.  WATER CAN RISE VERY QUICKLY.
 
FLOODING OF RURAL ROADS AND CITY STREETS WILL ALSO OCCUR.
 
A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT.  MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES.  DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR LOW SPOTS IF WATER COVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT.
 
MYERS

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

Local storm report, Jul 19, 8:28 PM CDT, 5 hours 8 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
828 PM THU JUL 19 1990

TIME (CDT)     EVENT

529 PM         BRIEF TORNADO TOUCHDOWN JUST EAST OF HUMESTON IN
               NORTHWEST WAYNE COUNTY.  WENT RIGHT BACK INTO
               CLOUDS.  NO KNOWN DAMAGES.

END/CHB

Nearby

Flash Flood Warnings in Iowa, 1990 Every flash flood warning in 1990

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.