Alert archive / Minnesota / Flash Flood Warnings in 2011

Flash Flood Warning 11, NWS Twin Cities, MN

July 23, 2011Steele County, Minnesota

NWS Twin Cities, MN issued this flash flood warning at Jul 23, 2011, 11:32 PM CDT for Steele County, Minnesota. It was in force for 3 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jul 23, 2011, 11:32 PM CDT (04:32 UTC)
Expired
Jul 24, 2011, 2:30 AM CDT
In force
3 hr
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Flood severity
None

County Steele County, MN

The radar

The Minneapolis radar (KMPX), 89 km from the middle of the area, began a volume at 04:32 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Jul 24, 2:00 AM CDTHEAVY RAIN 45 S Deerfield, MN

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 4.5 hours before the alert went out and 90 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 2011-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2128 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 2011-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 94 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
2128 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
814 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
212 m²/s²
Significant tornado parameter
2.0
Supercell composite
11.7

Open this sounding in Storm Lab

The text

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

242 
WGUS53 KMPX 240432
FFWMPX
MNC147-240730-
/O.NEW.KMPX.FF.W.0011.110724T0432Z-110724T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1132 PM CDT SAT JUL 23 2011

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHERN STEELE COUNTY IN SOUTH CENTRAL MINNESOTA...

* UNTIL 230 AM CDT

* AT 1131 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE
  WARNED AREA.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  OWATONNA.

THIS INCLUDES THE FOLLOWING STREAMS AND DRAINAGES...
CRANE CREEK...MAPLE CREEK...TURTLE CREEK...STRAIGHT RIVER...
MIDDLE FORK ZUMBRO RIVER...MEDFORD CREEK...AND TRIBUTARY STRAIGHT RIVER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

&&

LAT...LON 4414 9305 4402 9305 4401 9340 4414 9341

$$
2 follow-up statements
251 
WGUS73 KMPX 240641
FFSMPX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
141 AM CDT SUN JUL 24 2011

MNC147-240730-
/O.CON.KMPX.FF.W.0011.000000T0000Z-110724T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
STEELE MN-
141 AM CDT SUN JUL 24 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR NORTHERN STEELE COUNTY
UNTIL 230 AM CDT...

AT 136 AM CDT...NATIONAL WEATHER SERVICE RADAR CONTINUED TO INDICATE 
THUNDERSTORMS WITH VERY HEAVY RAINFALL MOVING ACROSS NORTHERN AND 
CENTRAL STEELE COUNTY. RADAR ESTIMATES SUGGEST THAT AROUND 4 INCHES 
OF RAIN HAS OCCURRED NEAR OWATONNA. 

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
OWATONNA.

STREET FLOODING HAS BEEN REPORTED IN A FEW AREAS OF OWATONNA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLOODING IS OBSERVED...ACT QUICKLY. DO NOT
ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND. DO NOT
STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

A FLASH FLOOD WARNING MEANS THAT FLASH FLOODING IS IMMINENT OR
OCCURRING. IF YOU ARE IN THE WARNING AREA...MOVE TO HIGHER GROUND
IMMEDIATELY. RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE
IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO
CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

&&

LAT...LON 4414 9305 4402 9305 4401 9340 4414 9341

$$
366 
WGUS73 KMPX 240726
FFSMPX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
226 AM CDT SUN JUL 24 2011

MNC147-240741-
/O.EXP.KMPX.FF.W.0011.000000T0000Z-110724T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
STEELE MN-
226 AM CDT SUN JUL 24 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR NORTHERN STEELE
COUNTY WILL BE ALLOWED TO EXPIRE AT 230 AM CDT...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS
AND CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING TO
RECEDE...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN OBSERVED...
PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4414 9305 4402 9305 4401 9340 4414 9341

$$

JPC

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 8:41 PM CDTSpecial Weather StatementMPXBlue Earth34 min
Jul 23, 8:43 PM CDTSpecial Weather StatementMPXBlue Earth47 min
Jul 23, 9:07 PM CDTSpecial Weather StatementMPXLe Sueur38 min
Jul 23, 9:27 PM CDTAreal Flood AdvisoryMPXBlue Earth, Le Sueur, Rice, Waseca3 hr
Jul 23, 9:49 PM CDTSpecial Weather StatementMPXRamsey41 min
Jul 23, 11:17 PM CDTAreal Flood AdvisoryMPXSteele3 hr
Jul 24, 2:32 AM CDTAreal Flood AdvisoryMPXSteele57 min

Nearby

Flash Flood Warnings in Minnesota, 2011Every flash flood warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.