Alert archive / Iowa / Flash Flood Warnings in 1993

Flash Flood Warning 103, NWS Des Moines, IA

August 14, 1993Buena Vista County, Pocahontas County, Iowa

NWS Des Moines, IA issued this flash flood warning at Aug 14, 1993, 12:41 PM CDT for Buena Vista County, Pocahontas County, Iowa. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Aug 14, 1993, 12:41 PM CDT (17:41 UTC)
Expired
Aug 14, 1993, 3:45 PM CDT
In force
3 hr
Issued by
NWS Des Moines, IA
Area
Whole counties

Counties Buena Vista County, IA, Pocahontas County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 5.7 hours before the alert went out and 198 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 1993-08-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1021 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 12:00Z on 1993-08-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 107 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
1021 J/kg
Mixed-layer CIN
-204 J/kg
Mixed-layer LCL
927 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
107 m²/s²
0-3 km storm-relative helicity
107 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.6

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 141742
FFWDSM
IAC021-151-142045-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1241 PM CDT SAT AUG 14 1993
 
THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  345 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION(S)S...
 
IN NORTHWEST IOWA
 
   ...SOUTHERN BUENA-VISTA COUNTY...SOUTHERN POCAHONTAS COUNTY
 
AT 1235 PM CDT VERY HEAVY RAINS WERE OCCURRING OVER THE SOUTHERN HALF OF
POCAHONTAS AND BUENA VISTA COUNTIES DUE TO SLOW-MOVING STORMS THAT WERE
PRODUCING DOWNPOURS.
 
SOME RIVERS AND CREEKS AFFECTED ARE LITTLE CEDAR CREEK...CEDAR CREEK
...OUTLET CREEK AND PRARIE CREEK AS WELL AS TRIBUTARIES OF THE NORTH
RACCOON RIVER.
 
 
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.  TO ESCAPE RISING WATER MOVE UP TO HIGHER GROUND.
 
A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT.  IT'S
IMPORTANT TO KNOW WHERE YOU ARE RELATIVE TO STREAMS...RIVERS...OR
CREEKS WHICH CAN BECOME KILLERS IN HEAVY RAINS.  CAMPERS SHOULD
AVOID CAMPING ALONG STREAMS OR CREEKS DURING THREATENING RAINS.
 
 
 
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, Aug 14, 8:47 AM CDT, 3 hours 54 minutes before
IAZALL-141440-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
847 AM CDT SAT AUG 14 1993

AT 833 AM CDT...A SMALL AREA OF INTENSE THUNDERSTORMS WAS CENTERED ABOUT
25 MILES WEST OF DES MOINES NEAR EARLHAM. VERY HEAVY RAIN ...GUSTY
WINDS...POSSIBLE SMALL HAIL AND FEQUENT DEADLY LIGHTNING CAN BE EXPECTED
WITH THESE STORMS.

THESE STORMS WERE PART OF A LARGER AREA OF SCATTERED SHOWERS AND
THUNDERSTORMS WHICH CONTINUED ACROSS THE WESTERN HALF OF IOWA. COVERAGE
WAS GREATEST ACROSS NORTHWEST IOWA.

MOVEMENT WAS EAST AT 20 MILES AN HOUR.

R A PRENTICE
Special weather statement, Aug 14, 9:49 AM CDT, 2 hours 52 minutes before
IAZALL-141540-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
949 AM CDT SAT AUG 14 1993

AT 926 AM CDT...TWO STRONG THUNDERSTORMS WERE LOCATED ACROSS CENTRAL
IOWA.

THE FIRST WAS CENTERED ABOUT 20 MILES WEST OF DES MOINES NEAR EARLHAM.
THIS STORM WAS MOVING SLOWLY EAST AT 5 TO 10 MILES AN HOUR AND HAS BEEN
PRODUCING LOCALLY HEAVY RAIN ACROSS NORTHWEST AND NORTH CENTRAL MADISON
COUNTY...AS WELL AS SOUTHWEST AND SOUTH CENTRAL DALLAS COUNTY.

THE SECOND STORM WAS LOCATED 25 MILES SOUTHWEST OF FORT DODGE OR 5
MILES SOUTH OF LOHRVILLE. THIS STORM WAS PRODUCING BRIEF VERY HEAVY
RAIN...GUSTY WINDS AND POSSIBLY SOME SMALL HAIL. BOTH STORMS WERE
PRODUCING FREQUENT DEADLY LIGHTNING.

THESE STORMS WERE PART OF A LARGER AREA OF SCATTERED SHOWERS AND
THUNDERSTORMS WHICH CONTINUED ACROSS THE WESTERN HALF OF IOWA. THIS
AREA WAS LOCATED WEST OF A LINE EXTENDING FROM THE MINNESOTA BORDER 15
MILES NORTHWEST OF BANCROFT...TO 10 MILES EAST OF AMES...TO 15 MILES
SOUTH OF DES MOINES.

MOVEMENT WAS EAST AT 15 MILES AN HOUR.

R A PRENTICE
Special weather statement, Aug 14, 10:49 AM CDT, 1 hour 52 minutes before
IAZALL-141640-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1049 AM CDT SAT AUG 14 1993

AT 1034 AM CDT...STRONG THUNDERSTORMS CONTINUED ACROSS NORTHWEST
AND CENTRAL IOWA. THESE STORMS WERE LOCATED 5 MILES SOUTHEAST OF
POCAHONTAS...5 MILES NORTH AND 10 MILES NORTHWEST OF ROCKWELL CITY...AND
BETWEEN FORT DODGE AND BOONE. THESE STORMS WILL PRODUCE BREIF VERY HEAVY
RAIN...GUSTY WINDS...POSSIBLE SMALL HAIL AND FREQUENT DEADLY LIGHTNING.

THESE STORMS WERE PART OF A LARGER AREA OF NUMEROUS SHOWERS AND
THUNDERSTORMS WHICH CONTINUED ACROSS NORTHWEST AND NORTH CENTRAL IOWA.
THIS AREA WAS LOCATED WEST OF A LINE EXTENDING FROM THE MINNESOTA BORDER
NORTH OF MASON CITY...TO 20 MILES NORTHEAST OF DES MOINES.

MOVEMENT WAS EAST AT 25 MILES AN HOUR.

R A PRENTICE
Special weather statement, Aug 14, 11:48 AM CDT, 53 minutes before
IAZALL-141740-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1148 AM CDT SAT AUG 14 1993

AT 1132 AM CDT...STRONG THUNDERSTORMS CONTINUED ACROSS NORTHWEST AND
CENTRAL IOWA. THESE STORMS WERE LOCATED 10 MILES SOUTHWEST OF STORM
LAKE...5 MILES NORTH AND 5 MILES WEST OF FORT DODGE...AND 5 MILES NORTH
OF NEVADA. THESE STORMS ARE CAPABLE OF PRODUCING VERY HEAVY RAIN...GUSTY
WINDS...SMALL HAIL AND FREQUENT DEADLY LIGHTNING.

THESE STORMS WERE PART OF A LARGER AREA OF NUMEROUS SHOWERS AND
THUNDERSTROMS WHICH CONTINUED ACROSS NORTHWEST AND NORTH CENTRAL IOWA.
THIS AREA WAS LOCATED NORTH OF A LINE EXTENDING FROM THE NEBRASKA BORDER
30 MILES SOUTH OF SIOUX CITY...TO 15 MILES EAST OF AMES...TO 10 MILE
WEST OF WATERLOO.

MOVEMENT WAS EAST AT 25 MILES AN HOUR.

R A PRENTICE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 11:36 AM CDTSevere Thunderstorm WarningDMXBuena Vista, Pocahontas39 min
Aug 14, 12:21 PM CDTSevere Thunderstorm WarningDMXCalhoun, Pocahontas39 min
Aug 14, 1:59 PM CDTFlash Flood WarningDMXHardin2 hr
Aug 14, 5:06 PM CDTSevere Thunderstorm WarningDMXLinn24 min
Aug 14, 5:17 PM CDTSevere Thunderstorm WarningDMXIowa28 min
Aug 14, 5:55 PM CDTSevere Thunderstorm WarningDMXMarion35 min
Aug 14, 6:08 PM CDTSevere Thunderstorm WarningDMXMahaska37 min
Aug 14, 6:21 PM CDTFlash Flood WarningDMXLinn118 min

Nearby

Flash Flood Warnings in Iowa, 1993Every flash flood warning in 1993

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.