Alert archive / Iowa / Flash Flood Warnings in 1993

Flash Flood Warning 124, NWS Des Moines, IA

August 30, 1993Crawford County, Iowa

NWS Des Moines, IA issued this flash flood warning at Aug 30, 1993, 1:52 AM CDT for Crawford County, Iowa. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Aug 30, 1993, 1:52 AM CDT (06:52 UTC)
Expired
Aug 30, 1993, 6:00 AM CDT
In force
4 hr
Issued by
NWS Des Moines, IA
Area
Whole counties

County Crawford County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 6.9 hours before the alert went out and 114 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 1993-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4054 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 00:00Z on 1993-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 172 square meters per square second.193958Sfc1 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
4054 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
760 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
172 m²/s²
0-3 km storm-relative helicity
263 m²/s²
Significant tornado parameter
4.0
Supercell composite
22.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 300653
FFWDSM
IAC047-301100-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
152 AM CDT MON AUG 30 1993
 
THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL  600 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION(S)...
 
IN WEST CENTRAL IOWA
 
   ...CRAWFORD COUNTY
 
AT 150 AM...THUNDERSTORMS...PRODUCING VERY HEAVY RAINFALL...WERE OVER
CRAWFORD COUNTY NORTH OF DENISON. MORE THUNDERSTORMS WEST INTO EASTERN
NEBRASKA WILL LIKELY CROSS THIS SAME AREA PRODUCING EXCESSIVE RAINFALL.
FLASH FLOODING IS LIKELY ALONG TRIBUTATIES OF THE SOLDIER RIVER AND THE
BOYER RIVER.
 
BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE
THE DANGERS OF FLOODS AND FLASH FLOODS.  IF FLASH FLOODING IS
OBSERVED...ACT QUICKLY.  MOVE UP TO ESCAPE FLOOD WATERS.  DO
NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.
 
 
JOHNSON

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 30, 12:11 AM CDT, 1 hour 41 minutes before
IAZ006-007-008-009-010-011-016-017-018-019-026-027-028-029-038-
039-040-300615-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
1215 AM CDT MON AUG 30 1993

...A FLASH FLOOD WATCH IS IN EFFECT FOR NORTHEAST AND NORTH CENTRAL
IOWA TONIGHT...

SCATTERED LIGHT RAIN SHOULD CONTINUE ALONG THE HIGHWAY 20 CORRIDOR
BETWEEN WATERLOO AND DUBUQUE.  ANOTHER AREA OF SHOWERS AND
THUNDERSTORMS WAS PUSHING INTO NORTH CENTRAL IOWA WITH THE LEADING
EDGE ABOUT 25 MILES WEST OF MASON CITY.  THIS SYSTEM HAS PRODUCED
OVER 2 INCHES OF RAINFALL IN THE SIOUX CITY AREA EARLIER TONIGHT
AND IS THE REASON FOR THE FLASH FLOOD WATCH OVERNIGHT IN NORTHEAST
AND NORTH CENTRAL IOWA.

HEAVY RAINS TONIGHT WILL MOST LIKLEY CAUSE FLOODING IN SOME STREAMS
AND RIVERS ACROSS NORTHEAST AND NORTH CENTRAL IOWA.  IF YOU LIVE
IN FLOOD PRONE AREAS...KEEP AN EYE ON THE WEATHER AND BE PREPARED
TO ACT QUICKLY IF FLOODING STARTS OR A WARNING IS ISSUED.

LINDENBERG
Special weather statement, Aug 30, 12:15 AM CDT, 1 hour 37 minutes before
IAZ006-007-008-009-010-011-016-017-018-019-026-027-028-029-038-
039-040-300615-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
1215 AM CDT MON AUG 30 1993

...A FLASH FLOOD WATCH IS IN EFFECT FOR NORTHEAST AND NORTH CENTRAL
IOWA TONIGHT...

SCATTERED LIGHT RAIN SHOULD CONTINUE ALONG THE HIGHWAY 20 CORRIDOR
BETWEEN WATERLOO AND DUBUQUE.  ANOTHER AREA OF SHOWERS AND
THUNDERSTORMS WAS PUSHING INTO NORTH CENTRAL IOWA WITH THE LEADING
EDGE ABOUT 25 MILES WEST OF MASON CITY.  THIS SYSTEM HAS PRODUCED
OVER 2 INCHES OF RAINFALL IN THE SIOUX CITY AREA EARLIER TONIGHT
AND IS THE REASON FOR THE FLASH FLOOD WATCH OVERNIGHT IN NORTHEAST
AND NORTH CENTRAL IOWA.

HEAVY RAINS TONIGHT WILL MOST LIKLEY CAUSE FLOODING IN SOME STREAMS
AND RIVERS ACROSS NORTHEAST AND NORTH CENTRAL IOWA.  IF YOU LIVE
IN FLOOD PRONE AREAS...KEEP AN EYE ON THE WEATHER AND BE PREPARED
TO ACT QUICKLY IF FLOODING STARTS OR A WARNING IS ISSUED.

LINDENBERG
Special weather statement, Aug 30, 12:40 AM CDT, 1 hour 12 minutes before
IAZALL-300640-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1240 AM CDT MON AUG 30 1993

...A FLASH FLOOD WATCH CONTINUES FOR THE NORTHWEST TWO THIRDS OF
   IOWA TONIGHT...

AT 1230 AM CDT...A LINE OF INTENSE THUNDERSTORMS WAS LOCATED IN
WEST CENTRAL THROUGH NORTHWEST INTO NORTHCENTRAL IOWA.  THIS
LINE OF THUNDERSTORMS EXTENDED FROM ONAWA...20 MILES SOUTH OF SIOUX
CITY...THROUGH IDA GROVE TO BUFFALO CENTER...ABOUT 35 MILES
NORTHWEST OF MASON CITY.  THE HEAVIEST STORM WAS LOCATED JUST SOUTH
OF IDAGROVE.  THESE STORM WILL PRODUCE EXTREMELY HEAVY RAIN...WIND GUSTS
OF 40 TO 50 MILES AN HOUR...NEARLY CONTINUOUS DEADLY LIGHTNING AND
POSSIBLY HAIL. THIS LINE OF STORMS WAS PART OF A MUCH LARGER AREA OF
SHOWERS AND SCATTERED STRONG THUNDERSTORMS LOCATED OVER THE NORTHWEST
THIRD OF IOWA. MOST OF THESE STORMS WERE ALONG AND NORTHWEST OF A LINE
FROM 25 MILES NORTH OF OMAHA TO FORT  DODGE AND EAST TO DUBUQUE.
NORTHWEST OF MASON CITY.

THE SHOWERS AND STORMS WERE MOVING EAST AT 25 MILES AN HOUR.

SCOTT
Special weather statement, Aug 30, 1:19 AM CDT, 33 minutes before
IAZ006-007-008-009-010-011-016-017-018-019-026-027-028-029-038-
039-040-300715-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
119 AM CDT MON AUG 30 1993

...A FLASH FLOOD WATCH REMAINS IN EFFECT FOR NORTHEAST AND NORTH CENTRAL
IOWA OVERNIGHT...

AT 115 AM...RADAR WAS SHOWING SHOWERS AND THUNDERSTORMS PRODUCING VERY
HEAVY RAINS FROM 30 MILES NORTH OF WATERLOO...TO 25 MILES NORTHEAST OF
WATERLOO.  THESE STORMS ARE GOING TO DUMP HEAVY RAINS IN THE TOWNS OF
NEW HAMPTON...WEST UNION...CALMAR...AND DECORAH.  THESE RAINS ARE GOING
TO CAUSE MINOR STREET FLOODING AND CAN CAUSE SMALL CREEKS AND STREAMS TO
RISE RAPIDLY.

REMEMBER...A FLASH FLOOD WATCH IS IN EFFECT FOR THIS AREA.  CONDITIONS
ARE FAVORABLE FOR FLASH FLOODING TONIGHT.  DO NOT ATTEMPT TO DRIVE
ACROSS WATER COVERING THE ROAD.  STAY AWAY FROM CREEKS AND STREAMS.

STAY TUNED TO YOUR NOAA WEATHER RADIO...OR LOCAL MEDIA FOR FURTHER
UPDATES AND POSSIBLE WARNINGS.

LINDENBERG
Special weather statement, Aug 30, 1:20 AM CDT, 32 minutes before
IAZ006-007-008-009-010-011-016-017-018-019-026-027-028-029-038-
039-040-300715-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
119 AM CDT MON AUG 30 1993

...A FLASH FLOOD WATCH REMAINS IN EFFECT FOR NORTHEAST AND NORTH CENTRAL
IOWA OVERNIGHT...

AT 115 AM...RADAR WAS SHOWING SHOWERS AND THUNDERSTORMS PRODUCING VERY
HEAVY RAINS FROM 30 MILES NORTH OF WATERLOO...TO 25 MILES NORTHEAST OF
WATERLOO.  THESE STORMS ARE GOING TO DUMP HEAVY RAINS IN THE TOWNS OF
NEW HAMPTON...WEST UNION...CALMAR...AND DECORAH.  THESE RAINS ARE GOING
TO CAUSE MINOR STREET FLOODING AND CAN CAUSE SMALL CREEKS AND STREAMS TO
RISE RAPIDLY.

REMEMBER...A FLASH FLOOD WATCH IS IN EFFECT FOR THIS AREA.  CONDITIONS
ARE FAVORABLE FOR FLASH FLOODING TONIGHT.  DO NOT ATTEMPT TO DRIVE
ACROSS WATER COVERING THE ROAD.  STAY AWAY FROM CREEKS AND STREAMS.

STAY TUNED TO YOUR NOAA WEATHER RADIO...OR LOCAL MEDIA FOR FURTHER
UPDATES AND POSSIBLE WARNINGS.`

LINDENBERG
Special weather statement, Aug 30, 1:50 AM CDT, 2 minutes before
IAZALL-300740-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1 40 AM CDT MON AUG 30 1993

...A FLASH FLOOD WATCH CONTINUES FOR THE NORTHWEST TWO THIRDS OF
   IOWA TONIGHT...

AT 1 30 AM CDT...AN AREA OF INTENSE THUNDERSTORMS WAS LOCATED IN
WEST CENTRAL IOWA BETWEEN ONAWA AND CARROLL...AND IN NORTH CENTRAL IOWA
NEAR BUFFALO CENTER.  THESE STORMS WILL PRODUCE EXTREMELY HEAVY
RAIN...NEARLY CONTINUOUS LIGHTNING AND POSSIBLY HAIL. THESE STORMS WERE
PART OF A MUCH LARGER AREA OF SHOWERS AND SCATTERED STRONG THUNDERSTORMS
LOCATED OVER THE NORTHWEST THIRD OF IOWA. MOST OF THESE STORMS WERE
ALONG AND NORTHWEST OF A LINE FROM 25 MILES NORTH OF OMAHA TO GUTTENBERG
...25 MILES NORTHWEST OF DUBUQUE.

THE SHOWERS AND STORMS WERE MOVING EAST AT 25 MILES AN HOUR.

SCOTT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 30, 1:29 AM CDTFlash Flood WarningDMXKossuth4 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.