Alert archive / Minnesota / Flash Flood Warnings in 1991

Flash Flood Warning 9, NWS Twin Cities, MN

July 21, 19914 counties in Minnesota

NWS Twin Cities, MN issued this flash flood warning at Jul 21, 1991, 7:41 PM CDT for 4 counties in Minnesota. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Jul 21, 1991, 7:41 PM CDT (00:41 UTC)
Expired
Jul 21, 1991, 9:45 PM CDT
In force
2 hr
Issued by
NWS Twin Cities, MN
Area
Whole counties

Counties Goodhue County, MN, Olmsted County, MN, Wabasha County, MN, Winona County, MN

The nearest sounding before it

Minneapolis, MN (KSTC), launched 00:00Z, 0.7 hours before the alert went out and 129 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 1991-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2851 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 1991-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
2851 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
775 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
130 m²/s²
Significant tornado parameter
1.3
Supercell composite
6.7

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KRST 220042
FFWRST
MNC049-109-157-169-220245-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ROCHESTER MN
741 PM CDT SUN JUL 21 1991
 
THE NATIONAL WEATHER SERVICE IN ROCHESTER MN HAS ISSUED A
FLASH FLOOD WARNING         EFFECTIVE UNTIL  1000 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHEAST MINNESOTA
 
   ...NORTHEASTERN GOODHUE COUNTY...NORTHEASTERN OLMSTED COUNTY
   ...WABASHA COUNTY...WINONA COUNTY
 
THIS WARNING INCLUDES THE COMMUNITIES OF RED WING...LAKE CITY...
WABASHA...ZUMBRO FALLS...PLAINVIEW...ST CHARLES...WINONA...AND
WHITEWATER STATE PARK.
 
SLOW-MOVING AND INTENSE THUNDERSTORMS HAVE BEEN PRODUCING
TORRENTIAL RAINS ACROSS SOUTHEAST MINNESOTA...NORTHEAST OF A
FROM NEAR CANNON FALLS TO ZUMBROTA TO EYOTA TO THE SOUTHEAST
CORNER OF OLMSTED COUNTY NEAR CHATFIELD TO THE SOUTHEAST
CORNER OF WINONA COUNTY NEAR LA CRESCENT AND LA CROSSE.
 
RAINFALLS...THUS FAR...OF 1.50 TO ALMOST 2.50 INCHES HAVE
BEEN REPORTED IN THE WARNING AREA...AND RADAR INDICATED THAT
VERY HEAVY RAINS PERSIST ACROSS THIS AREA.
 
THE THUNDERSTORMS WERE MOVING SLOWLY TO THE NORTH AT 15 MILES
AN HOUR...BUT...CONTINUED TO DEVELOP.
 
PERSONS IN FLASH FLOOD PRONE AREAS SHOULD TAKE ACTION TO PROTECT
LIVES AND OR PROPERTY.
 
 
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.
 
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 CcOVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT.  TO ESCAPE RISING WATER MOVE UP TO HIGHER GROUND.

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 21, 7:33 PM CDTSevere Thunderstorm WarningMPXLac qui Parle57 min
Jul 21, 8:17 PM CDTSevere Thunderstorm WarningMPXChippewa, Lac qui Parle, Swift58 min
Jul 21, 8:34 PM CDTSevere Thunderstorm WarningMPXHennepin26 min
Jul 21, 10:10 PM CDTFlash Flood WarningMPXWabasha, Winona2 hr
Jul 21, 11:55 PM CDTFlash Flood WarningMPXWabasha, Winona5 hr
Jul 22, 1:57 AM CDTFlash Flood WarningMPXDodge, Goodhue, Olmsted, Steele3 hr

Nearby

Flash Flood Warnings in Minnesota, 1991Every flash flood warning in 1991

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.