Alert archive / Iowa / Flash Flood Warnings in 1994

Flash Flood Warning 1, NWS Des Moines, IA

May 22, 1994Calhoun County, Iowa

NWS Des Moines, IA issued this flash flood warning at May 22, 1994, 7:40 PM CDT for Calhoun County, Iowa. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
May 22, 1994, 7:40 PM CDT (00:40 UTC)
Expired
May 22, 1994, 10:45 PM CDT
In force
3 hr
Issued by
NWS Des Moines, IA
Area
Whole counties

County Calhoun County, IA

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 0.7 hours before the alert went out and 186 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 1994-05-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 159 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 1994-05-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 13 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
159 J/kg
Mixed-layer CIN
-147 J/kg
Mixed-layer LCL
2414 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
13 m²/s²
0-3 km storm-relative helicity
90 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 230041
FFWDSM
IAC025-230345-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
740 PM CDT SUN MAY 22 1994
 
THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 1045 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN WEST CENTRAL IOWA
 
   ...NORTHERN CALHOUN COUNTY
 
DOPPLER RADAR INDICATED THAT RAINFALL BETWEEN 3 AND 4 INCHES HAD FALLEN
BETWEEN 6 AND 730 PM. THE THUNDERSTORM REMAINED OVER NORTHWEST CALHOUN
COUNTY ABOUT 15 MILES NORTHWEST OF ROCKWELL CITY OR 35 MILES WEST OF
FORT DODGE. THE THUNDERSTORM WAS STATIONARY A 730 PM AND SHOULD CONTINUE
TO PRODUCE VERY HEAVY RAINFALL.
 
DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY.  THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO
CROSS SAFELY.  VEHICLES CAUGHT IN RISING WATER SHOULD BE
ABANDONED QUICKLY.  MOVE TO HIGHER GROUND.
 
 
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, May 22, 4:35 PM CDT, 3 hours 5 minutes before
IAZALL-222240-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IOWA
435 PM CDT SUN MAY 22 1994

AT 425 PM CDT...AN AREA OF THUNDERSTORMS HAD DEVELOPED FROM WEST CENTRAL
INTO CENTRAL IOWA. THE STORMS WERE IN AN AREA 20 MILES WIDE FROM IDA
GROVE...40 MILES EAST OF SIOUX CITY...TO STORY CITY...40 MILES NORTH OF
DES MOINES. THE HEAVIEST RAIN WAS LOCATED BETWEEN LAKE VIEW AND LAKE
CITY...30 MILES SOUTHWEST OF FORT DODGE.

THESE STORMS ARE CAPABLE OF PRODUCING BRIEF HEAVY RAIN...SMALL HAIL...
AND GUSTY WINDS.

MOVEMENT OF THE PRECIPITATION COULD NOT BE DETERMINED DUE TO ITS RECENT
DEVELOPMENT.

BAILEY
Special weather statement, May 22, 6:05 PM CDT, 1 hour 35 minutes before
IAZALL-240000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IOWA
605 PM CDT SUN MAY 22 1994

...LOCALLY HEAVY RAIN HAD FALLEN OVER WEST CENTRAL IOWA...

AT 600 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A GROUP OF
THUNDERSTORMS OVER WEST CENTRAL IOWA.  THE STORMS WERE LOCATED BETWEEN
FORT DODGE AND JEFFERSON...OR 60 MILES NORTHWEST OF DES MOINES.  THE
THUNDERSTORMS WERE MOVING SLOWLY SOUTHEAST AT 10 MPH.

THUNDERSTORMS SHOULD CONTINUE BETWEEN FORT DODGE AND JEFFERSON AND MOVE
INTO THE BOONE AND WEBSTER CITY AREAS BY 700 PM.  ALTHOUGH THE
THUNDERSTORMS ARE NOT EXPECTED TO BE SEVERE...LOCALLY HEAVY RAIN AND
POSSIBLE SMALL HAIL CAN BE EXPECTED.

DOPPLER RADAR INDICATED THAT BETWEEN AN INCH AND AN INCH AND ONE HALF OF
RAIN HAS FALLEN OVER NORTHWEST GREEN COUNTY BETWEEN JEFFERSON AND LAKE
CITY.  THIS AMOUNT OF RAINFALL SHOULD PRODUCE STANDING WATER ON AREA
ROADS.

MOTORISTS ALONG HIGHWAYS 20...30 AND 169 IN BOONE AND FORT DODGE AREA
SHOULD BE PREPARED FOR VERY HEAVY RAIN.  YOU SHOULD REDUCE YOUR SPEED.
REMEMBER...WET ROADS MAY BE SLICK DUE TO OIL ON THE ROAD SURFACES SINCE
IT HAS BEEN DRY RECENTLY BEFORE THIS AFTERNOONS RAINFALL.

JOHNSON
Special weather statement, May 22, 6:15 PM CDT, 1 hour 25 minutes before
IAZALL-240000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IOWA
605 PM CDT SUN MAY 22 1994

...LOCALLY HEAVY RAIN HAD FALLEN OVER WEST CENTRAL IOWA...

AT 600 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A GROUP OF
THUNDERSTORMS OVER WEST CENTRAL IOWA.  THE STORMS WERE LOCATED BETWEEN
FORT DODGE AND JEFFERSON...OR 60 MILES NORTHWEST OF DES MOINES.  THE
THUNDERSTORMS WERE MOVING SLOWLY SOUTHEAST AT 10 MPH.

THUNDERSTORMS SHOULD CONTINUE BETWEEN FORT DODGE AND JEFFERSON AND MOVE
INTO THE BOONE AND WEBSTER CITY AREAS BY 700 PM.  ALTHOUGH THE
THUNDERSTORMS ARE NOT EXPECTED TO BE SEVERE...LOCALLY HEAVY RAIN AND
POSSIBLE SMALL HAIL CAN BE EXPECTED.

DOPPLER RADAR INDICATED THAT BETWEEN AN INCH AND AN INCH AND ONE HALF OF
RAIN HAS FALLEN OVER NORTHWEST GREEN COUNTY BETWEEN JEFFERSON AND LAKE
CITY.  THIS AMOUNT OF RAINFALL SHOULD PRODUCE STANDING WATER ON AREA
ROADS.

MOTORISTS ALONG HIGHWAYS 20...30 AND 169 IN BOONE AND FORT DODGE AREA
SHOULD BE PREPARED FOR VERY HEAVY RAIN.  YOU SHOULD REDUCE YOUR SPEED.
REMEMBER...WET ROADS MAY BE SLICK DUE TO OIL ON THE ROAD SURFACES SINCE
IT HAS BEEN DRY RECENTLY BEFORE THIS AFTERNOONS RAINFALL.
B
JOHNSON
Special weather statement, May 22, 7:35 PM CDT, 5 minutes before
IAZALL-230140-

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IOWA
735 PM CDT SUN MAY 22 1994

AT 725 PM CDT...AN AREA OF THUNDERSTORMS PRODUCING LOCALLY HEAVY RAIN
CONTINUED FROM WEST CENTRAL THROUGH CENTRAL AND NORTH CENTRAL IOWA AND
INTO EAST CENTRAL IOWA. THE STORMS WERE IN AN AREA 60 MILES WIDE FROM
MANILLA...50 MILES NORTHEAST OF COUNCIL BLUFFS...TO JUST SOUTHWEST OF
WATERLOO. THE STRONGEST OF THE STORMS WAS OVER THE TOWN OF MANNING...60
MILES NORTHEAST OF COUNCIL BLUFFS.

THESE STORMS HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY RAINFALL AND
PEA SIZED HAIL.

MOVEMENT OF THE PRECIPITATION WAS EAST AT 15 MILES AN HOUR.

BAILEY

Nearby

Flash Flood Warnings in Iowa, 1994Every flash flood warning in 1994

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.