Alert archive / Minnesota / Flash Flood Warnings in 1991

Flash Flood Warning 10, NWS Twin Cities, MN

July 21, 1991Wabasha County, Winona County, Minnesota

NWS Twin Cities, MN issued this flash flood warning at Jul 21, 1991, 10:10 PM CDT for Wabasha County, Winona County, Minnesota. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Jul 21, 1991, 10:10 PM CDT (03:10 UTC)
Expired
Jul 22, 1991, 12:15 AM CDT
In force
2 hr
Issued by
NWS Twin Cities, MN
Area
Whole counties

Counties Wabasha County, MN, Winona County, MN

The nearest sounding before it

Minneapolis, MN (KSTC), launched 00:00Z, 3.2 hours before the alert went out and 149 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°0°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 220312
FFWRST
MNC157-169-220515-
 
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ROCHESTER MN
1010 PM CDT SUN JUL 21 1991
 
THE NATIONAL WEATHER SERVICE IN ROCHESTER MN HAS ISSUED A
FLASH FLOOD WARNING         EFFECTIVE UNTIL MIDNIGHT CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHEAST MINNESOTA
 
   ...WABASHA COUNTY...WINONA COUNTY
 
THIS WARNING INCLUDES THE COMMUNITIES OF LAKE CITY...WABASHA...
PLAINVIEW...STOCKTON...AND WINONA...AND WHITEWATER STATE PARK.
 
SLOW-MOVING THUNDERSTORMS CONTINUED TO DEVELOP AND UNLOAD VERY
HEAVY RAINS OVER PARTS OF SOUTHEAST MINNESOTA...PARTICULARLY ON
WINONA AND WABASHA COUNTIES.
 
TORRENTIAL RAINFALL AMOUNTS AROUND TWO TO MORE THAN FIVE INCHES
HAVE DELUGED THESE AREAS...ESPECIALLY IN THE STOCKTON TO WABASHA
AREAS.  WINONA COUNTY OFFICIALS ARE REQUESTING NO TRAVEL IN THE
COUNTY...EXCEPT TO PROTECT LIVES.
 
 
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 COVERS
THE ROADWAY.  NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT.  TO ESCAPE RISING WATER MOVEZ UP TO HIGHER GROUND.
 
MOST DEATHS IN FLASH FLOODING 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.

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, Jul 21, 7:00 PM CDT, 3 hours 10 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
650 PM CDT SUN JUL 21 1991

...FLASH FLOOD WATCH FOR MUCH OF SOUTHERN MINNESOTA FOR TONIGHT...INCLUDING
THE TWIN CITIES METRO AREA...
...A LINE OF THUNDERSTORMS 40 MILES SOUTH OF THE TWIN CITIES WAS BEGINING TO
MOVE NORTHWARD AT 10 MPH AND AT THIS RATE WILL BE IN THE SOUTHERN TWIN CITIES
METRO AREA BETWEEN 730 AND 800 PM...

AT 640 PM...POWERFUL THUNDERSTORMS CONTINUE DEVELOP OVER SOUTH CENTRAL AND
SOUTHEAST MINNESOTA...SOUTH OF THE TWIN CITIES...AND MORE POWERFUL STORMS WERE
MOVING INTO WESTERN MINNESOTA FROM THE DAKOTAS. SOME OF THESE STORMS WERE
PRODUCING INTENSE FLOODING TYPE RAINFALLS...STRONG GUSTY WINDS OF 50 TO 60 MPH
AND POSSIBLY SOME HAIL. THE MOST INTENSE RAINFALL WAS IN SOUTHEAST MINNESOTA
NEAR THE MISSISSIPPI RIVER IN WINONA COUNTY BETWEEN ROCHESTER AND WINONA...NEAR
FEEMONT AND UTICA.

ANOTHER AREA OF STRONG THUNDERSTORMS WAS OVER SOUTH CENTRAL MINNESOTA...SOUTH
OF NEW ULM. AND FROM MANKATO AND EAST TO WASECA AND OWATONNA.

THIS IS A DANGEROUS WEATHER SITUATION...BECAUSE THE POTENTIAL FOR FLOODING
AND SEVERE WEATHER IS VERY HIGH OVER SOUTHERN MINNESOTA...THIS EVENING.
BE PREPARED FOR THE WORST AND...BE PREPARED TO MOVE TP A PLACE OF SAFETY IF
SEVERE WEATHER APPROACHES OR IF FLOODING IS OCCURRING.
Special weather statement, Jul 21, 7:14 PM CDT, 2 hours 56 minutes before
MNZALL-220100-
SPECIAL WEATHER STATEMENT...CORRECTED FOR CODING...
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
650 PM CDT SUN JUL 21 1991

...FLASH FLOOD WATCH FOR MUCH OF SOUTHERN MINNESOTA FOR TONIGHT...INCLUDING
THE TWIN CITIES METRO AREA...
...A LINE OF THUNDERSTORMS 40 MILES SOUTH OF THE TWIN CITIES WAS BEGINING TO
MOVE NORTHWARD AT 10 MPH AND AT THIS RATE WILL BE IN THE SOUTHERN TWIN CITIES
METRO AREA BETWEEN 730 AND 800 PM...

AT 640 PM...POWERFUL THUNDERSTORMS CONTINUE DEVELOP OVER SOUTH CENTRAL AND
SOUTHEAST MINNESOTA...SOUTH OF THE TWIN CITIES...AND MORE POWERFUL STORMS WERE
MOVING INTO WESTERN MINNESOTA FROM THE DAKOTAS. SOME OF THESE STORMS WERE
PRODUCING INTENSE FLOODING TYPE RAINFALLS...STRONG GUSTY WINDS OF 50 TO 60 MPH
AND POSSIBLY SOME HAIL. THE MOST INTENSE RAINFALL WAS IN SOUTHEAST MINNESOTA
NEAR THE MISSISSIPPI RIVER IN WINONA COUNTY BETWEEN ROCHESTER AND WINONA...NEAR
FEEMONT AND UTICA.

ANOTHER AREA OF STRONG THUNDERSTORMS WAS OVER SOUTH CENTRAL MINNESOTA...SOUTH
OF NEW ULM. AND FROM MANKATO AND EAST TO WASECA AND OWATONNA

THIS IS A DANGEROUS WEATHER SITUATION...BECAUSE THE POTENTIAL FOR FLOODING
AND SEVERE WEATHER IS VERY HIGH OVER SOUTHERN MINNE:SOTA...THIS EVENING.
BE PREPARED FOR THE WORST AND...BE PREPARED TO MOVE TP A PLACE OF SAFETY IF
SEVERE WEATHER APPROACHES OR IF FLOODING IS OCCURRING.
Special weather statement, Jul 21, 7:46 PM CDT, 2 hours 24 minutes before
MNZALL-220230-
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
745 PM CDT SUN JUL 21 1991

...STRONG THUNDERSTORMS MOVING INTO THE SOUTHERN PORTIONS OF THE
TWIN CITIES METROPOLITIAN AREA...
...SEVERE THUNDERSTORM WATCH POSTED FOR SOUTHERN MINNESOTA UNTIL
MIDNIGHT...INCLUDNG THE TWIN CITIES...
...TORNADO WATCH CONTINUES FOR SOUTHWEST AND WEST CENTRAL MINNESOTA
TILL 11 PM CDT...

POWERFUL THUNDERSTORMS CONTINUE DEVELOP AND MOVE NORTHWARD FROM ACROSS
SOUTHERN MINNESOTA. THE LEADING EDGE OF THIS AREA WAS CROSSING INTO
THE SOUTHERN COUNTIES OF THE TWIN CITIES METROPOLITIAN AREA. THESE
STORMS HAVE THE POTIENTAL TO TORRENTIAL RAINS...LARGE HAIL...STONG
WINDS AND DANGEROUS LIGHTNING. THE STRONGEST OF THESE STORMS EXTENDED
FROM CENTRAL SIBLEY COUNTY EAST INTO WESTERN SCOTT COUNTY. THESE
STORMS WILL MOVE NORTHWARD INTO THE HEART OF THE METROPOLITIAN AREA
DURNG THE NEXT SEVERAL HOURS.

PERSONS OUT AND ABOUT SHOULD KEEP A WATCHFUL EYE ON THE SKY AND LISTEN
FOR FURTHER STATEMENTS OR WARNING CONCERNING THESE POTIENTALLY DANGEROUS
STORMS.

IN ADDITION A FLASH FLOOD WATCH ALSO REMAIN IN EFFECT FOR MUCH OF
SOUTHERN TONIGHT. BECAUSE THE POTENTIAL FOR FLOODING AND SEVERE WEATHER
IS VERY HIGH PERSONS IN THE WATCH AREA MUST BE PREPARED FOR THE WORST
AND...BE PREPARED TO MOVE TO A PLACE OF SAFETY IF SEVERE WEATHER
APPROACHES OR IF FLOODING IS OCCURRING.

OTHER SEVERE THUNDERSTORMS WERE DROPING SOUTHEAST ALONG THE MINNESOTA
RIVER WHERE WARNING HAVEBEEN POSTED FOR THE THREAT OF LARGE HAIL AND
STRONG WINDS. TO THE SOUTHEAST ALONG THE MISSISSIPPI RIVER FROM RED WING
TO NORTH OF CALADONIA POWERFUL THUNDERSTORMS ARE ALSO PRODUCING GOLFBALL
DIAMETER HAIL AND RAgIN IN THE 1-2 INCH RANGE.

ACROSS SOUTHERN MINNESOTA THESE THUNDERSTORMS WERE MOVING NORTH AT 10 TO
15 MPH WHILE THE STRONG ACTIVITY IN WEST CENTRAL MINNESOTA WAS DROPPING
SOUTHEAST AT 15 TO 20 MPH.
DOMBROWSKY
Special weather statement, Jul 21, 8:49 PM CDT, 1 hour 21 minutes before
MNZ016-220400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS MN
854 PM CDT SUN JUL 21 1991

...SEVERE THUNDERSTORM WARNING FOR SOUTHERN HENNEPIN COUNTY IS CANCELLED
AS OF 850 PM CDT THIS EVENING...

THUNDERSTORM ACTIVITY HAS MOVED NORTHWARD OUT OF SOUTHERN HENNIPEN AND
NO LONGER CONSTITUTES A SEVERE WEATHER THREAT TO THE SOUTH METRO.

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, 7:41 PM CDTFlash Flood WarningMPXGoodhue, Olmsted, Wabasha, Winona2 hr
Jul 21, 8:17 PM CDTSevere Thunderstorm WarningMPXChippewa, Lac qui Parle, Swift58 min
Jul 21, 8:34 PM CDTSevere Thunderstorm WarningMPXHennepin26 min
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.