Alert archive / Iowa / Flash Flood Warnings in 1993

Flash Flood Warning 92, NWS Des Moines, IA

August 9, 1993Chickasaw County, Iowa

NWS Des Moines, IA issued this flash flood warning at Aug 9, 1993, 10:40 PM CDT for Chickasaw County, Iowa. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Aug 9, 1993, 10:40 PM CDT (03:40 UTC)
Expired
Aug 10, 1993, 1:00 AM CDT
In force
2 hr
Issued by
NWS Des Moines, IA
Area
Whole counties

County Chickasaw County, IA

The nearest sounding before it

Minneapolis, MN (KSTC), launched 00:00Z, 3.7 hours before the alert went out and 224 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, Minneapolis, MN at 00:00Z on 1993-08-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 490 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, Minneapolis, MN at 00:00Z on 1993-08-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
490 J/kg
Mixed-layer CIN
-81 J/kg
Mixed-layer LCL
1739 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
94 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KALO 100338
FFWALO
IAC037-100600-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE WATERLOO IA
1040 PM CDT MON AUG 9 1993
 
THE NATIONAL WEATHER SERVICE IN WATERLOO HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 100 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN NORTHEAST IOWA
 
   ...SOUTHERN CHICKASAW COUNTY
 
AT 1030 PM OFFICIALS FROM CHICKASAW COUNTY WERE INDICATING THAT FLASH
FLOODING IS AND WILL BE OCCURRING ALONG THE PLUM CREEK NEAR
FREDERICKSBURG AND IN THE FARMLANDS ALONG THE WAPSIPINICON RIVER. RADAR
SHOWED THAT THE RAIN HAD CLEARED THE COUNTY...HOWEVER THE 3 TO 4 INCHES
OF RAIN THAT OCCURRED EARLIER THIS EVENING IN THE NEW HAMPTON AREA...IS
MOVING DOWNSTREAM AND WILL LIKELY ENHANCE FLASH FLOOD POTENTIAL ALONG
THE AFOREMENTIONED WATERWAYS.
 
PEOPLE IN THE FREDERICKSBURG AREA LIVING ALONG THE PLUM CREEK SHOULD
MOVE TO HIGHER GROUNDS AS FLASH FLOODING OCCURS.
 
DO NOT STAY IN AREAS SUBJECT TO FLOODxING WHEN WATER BEGINS RISING.
ACT QUICKLY.  MOVE UP TO ESCAPE FLOOD WATERS.  IT IS HARDER TO
RECOGNIZE THE DANGERS OF FLOODS AND FLASH FLOODS AT NIGHT.
 
COLLAR
 
&

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 9, 8:40 PM CDT, 2 hours before
IAZALL-100240-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
840 PM CDT MON AUG 9 1993

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR MUCH OF THE NORTHERN HALF
   OF IOWA UNTIL 10 PM THIS EVENING...

AT 830 PM CDT...INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN AND HAIL WERE
LOCATED OVER NORTH CENTRAL AND NORTHEAST IOWA...AND DEVELOPING IN NORTH
WEST IOWA.  THESE THUNDERSTORMS WERE LOCATED NORTH OF A LINE EXTENDING
FROM SIOUX CITY TO DAVENPORT.

THE HEAVIEST THUNDERSTORMS IN NORTH CENTRAL IOWA WERE LOCATED ALONG A LINE
EXTENDING FROM BELMOND...25 MILES SOUTHWEST OF MASON CITY...TO CHARLES
CITY...30 MILES EAST OF MASON CITY.  VERY HEAVY RAINS...WINDS IN EXCESS OF
40 MILES AN HOUR...AND HAIL MAY BE EXPECTED WITH THE PASSAGE OF THESE
THUNDERSTORMS.

THE THUNDERSTORMS WERE MOVING SOUTHEAST AT 35 MILES AN HOUR.

SCOTT
Special weather statement, Aug 9, 8:54 PM CDT, 1 hour 46 minutes before
IAZALL-100240-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
840 PM CDT MON AUG 9 1993

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR MUCH OF THE NORTHERN HALF
   OF IOWA UNTIL 10 PM THIS EVENING...

AT 830 PM CDT...INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN AND HAIL WERE
LOCATED OVER NORTH CENTRAL AND NORTHEAST IOWA...AND DEVELOPING IN NORTH
WEST IOWA.  THESE THUNDERSTORMS WERE LOCATED NORTH OF A LINE EXTENDING
FROM SIOUX CITY TO DAVENPORT.

THE HEAVIEST THUNDERSTORMS IN NORTH CENTRAL IOWA WERE LOCATED ALONG A LINE
EXTENDING FROM BELMOND...25 MILES SOUTHWEST OF MASON CITY...TO CHARLES
CITY...30 MILES EAST OF MASON CITY.  VERY HEAVY RAINS...WINDS IN E(XCESS OF
40 MILES AN HOUR...AND HAIL MAY BE EXPECTED WITH THE PASSAGE OF THESE
THUNDERSTORMS.

THE THUNDERSTORMS WERE MOVING SOUTHEAST AT 35 MILES AN HOUR.

SCOTT
Special weather statement, Aug 9, 9:35 PM CDT, 1 hour 5 minutes before
IAZ006-007-008-009-010-011-016-017-018-019-026-027-028-029-038-
039-040-100330-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
935 PM CDT MON AUG 9 1993

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PARTS OF NORTHEAST IOWA
ALONG THE HIGHWAY 20 CORRIDOR UNTIL 3AM CDT...

AT 935 PM CDT THUNDERSTORMS CONTINUED ACROSS MUCH OF NORTH CENTRAL AND
NORTHEAST IOWA.  THESE THUNDERSTORMS WERE MOVING SOUTHEAST AT 25 MILES
AN HOUR.  THEY WILL AFFECT JUST ABOUT ALL CITIES AND TOWNS SOUTH OF
HIGHWAY 18...WATERLOO...GRUNDY CENTER...PARKERSBURG...NEW HAMPTON...
OELWEIN AND CHARLES CITY.

THESE THUNDERSTORMS COULD CAUSE SOME URBAN AND SMALL STREAM FLOODING
FROM VERY HEAVY RAINS ALONG WITH GUSTY WINDS...LIGHTNING AND HAIL.
PEOPLE IN NORTHEAST AND NORTH CENTRAL IOWA SHOULD CONTINUE TO MONITOR
THE WEATHER THIS EVENING AND LISTEN TO NOAA WEATHER RADIO...TV AND
RADIO FOR LATER UPDATES AND STATEMENTS.

A FLASH FLOOD WARNING IS IN EFFECT UNTIL 11 PM CDT FOR CHICKASAW
COUNTY WHICH IS ABOUT 30 MILES NORTH OF WATERLOO.

ROBB
Special weather statement, Aug 9, 9:43 PM CDT, 57 minutes before
IAZ006-007-008-009-010-011-016-017-018-019-026-027-028-029-038-
039-040-100330-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
935 PM CDT MON AUG 9 1993

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PARTS OF NORTHEAST IOWA
ALONG THE HIGHWAY 20 CORRIDOR UNTIL 3AM CDT...

AT 935 PM CDT THUNDERSTORMS CONTINUED ACROSS MUCH OF NORTH CENTRAL AND
NORTHEAST IOWA.  THESE THUNDERSTORMS WERE MOVING SOUTHEAST AT 25 MILES
AN HOUR.  THEY WILL AFFECT JUST ABOUT ALL CITIES AND TOWNS SOUTH OF
HIGHWAY 18...WATERLOO...GRUNDY CENTER...PARKERSBURG...NEW HAMPTON...
OELWEIN AND CHARLES CITY.

THESE THUNDERSTORMS COULD CAUSE SOME URBAN AND SMALL STREAM FLOODING
FROM VERY HEAVY RAINS ALONG WITH GUSTY WINDS...LIGHTNING AND HAIL.
PEOPLE IN NORTHEAST AND NORTH CENTRAL IOWA SHOULD CONTINUE TO MONITOR
THE WEATHER THIS EVENING AND LISTEN TO NOAA WEATHER RADIO...TV AND
RADIO FOR LATER UPDATES AND STATEMENTS.

A FLASH FLOOD WARNING IS IN EFFECT. UNTIL 11 PM CDT FOR CHICKASAW
COUNTY WHICH IS ABOUT 30 MILES NORTH OF WATERLOO.

ROBB
Special weather statement, Aug 9, 9:45 PM CDT, 55 minutes before
IAZALL-100340-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
945 PM CDT MON AUG 9 1993

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR CENTRAL AND EASTERN IOWA
   UNTIL 3AM...

AT 930 PM CDT...INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN AND HAIL WERE
LOCATED OVER NORTHWEST...NORTHCENTRAL AND EAST CENTRAL IOWA.  THE MOST
INTENSE THUNDERSTORMS WITH THE HEAVIEST RAINS AND SOME HAIL WERE LOCATED
ALONG A NARROW LINE...ABOUT 15 MILES WIDE...AND EXTENDING FROM JUST
NORTH OF STORM LAKE...THROUGH IOWA FALLS TO CEDAR RAPIDS.  VERY HEAVY RAINS
...STRONG GUSTY WINDS AND HAIL CAN BE EXPECTED WITH THESE STORMS.

OTHER SHOWERS AND THUNDERSTORMS WERE LOCATED NORTH OF THIS LINE...EXTENDING
NORTH TO NEAR THE MINNESOTA BORDER...AND EAST INTO ADJACENT PARTS OF
NORTHWEST ILLINOIS AND SOUTHWEST WISCONSIN.

THE STORMS WERE MOVING TO THE SOUTHEAST AT 35 MILES AN HOUR.

SCOTT
Special weather statement, Aug 9, 10:00 PM CDT, 40 minutes before
IAZALL-100340-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
945 PM CDT MON AUG 9 1993

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR CENTRAL AND EASTERN IOWA
   UNTIL 3AM...

AT 930 PM CDT...INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN AND HAIL WERE
LOCATED OVER NORTHWEST...NORTHCENTRAL AND EAST CENTRAL IOWA.  THE MOST
INTENSE THUNDERSTORMS WITH THE HEAVIEST RAINS AND SOME HAIL WERE LOCATED
ALONG A NARROW LINE...ABOUT 15 MILES WIDE...AND EXTENDING FROM JUST
NORTH OF STORM LAKE...THROUGH IOWA FALLS TO CEDAR RAPIDS.  VERY HEAVY RAINS
...STRONG GUSTY WINDS AND HAIL CAN BE EXPECTED WITH THESE STORMS.

OTHER SHOWERS AND THUNDERSTORMS WERE LOCATED NORTH OF TnHIS LINE...EXTENDING
NORTH TO NEAR THE MINNESOTA BORDER...AND EAST INTO ADJACENT PARTS OF
NORTHWEST ILLINOIS AND SOUTHWEST WISCONSIN.

THE STORMS WERE MOVING TO THE SOUTHEAST AT 35 MILES AN HOUR.

SCOTT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 7:05 PM CDTSevere Thunderstorm WarningDMXWorth33 min
Aug 9, 7:35 PM CDTSevere Thunderstorm WarningDMXBuchanan55 min
Aug 9, 8:00 PM CDTFlash Flood WarningDMXChickasaw3 hr
Aug 9, 8:33 PM CDTSevere Thunderstorm WarningDMXLinn42 min
Aug 9, 8:40 PM CDTSevere Thunderstorm WarningDMXButler50 min
Aug 9, 10:48 PM CDTFlash Flood WarningDMXLinn4 hr
Aug 9, 11:19 PM CDTSevere Thunderstorm WarningDMXCalhoun26 min
Aug 9, 11:19 PM CDTSevere Thunderstorm WarningDMXGreene41 min
Aug 9, 11:31 PM CDTFlash Flood WarningDMXIowa3 hr

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.