Alert archive / North Dakota / Flash Flood Warnings in 2011

Flash Flood Warning 2, NWS Grand Forks, ND

May 9, 2011Cass County, Richland County, North Dakota; Clay County, Minnesota

NWS Grand Forks, ND issued this flash flood warning at May 9, 2011, 12:42 AM CDT for Cass County, Richland County, North Dakota; Clay County, Minnesota. It took effect at May 9, 2011, 12:47 AM CDT. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 9, 2011, 12:42 AM CDT (05:42 UTC)
In effect from
May 9, 2011, 12:47 AM CDT
Expired
May 9, 2011, 7:00 AM CDT
In force
6 hr
Issued by
NWS Grand Forks, ND
Area
Storm-based polygon
Flood severity
None

Counties Clay County, MN, Cass County, ND, Richland County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 111 km from the middle of the area, began a volume at 05:41 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.

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 5.7 hours before the alert went out and 220 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, Aberdeen, SD at 00:00Z on 2011-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Aberdeen, SD at 00:00Z on 2011-05-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 156 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1839 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
156 m²/s²
0-3 km storm-relative helicity
413 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.1

Open this sounding in Storm Lab

The text

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

913 
WGUS53 KFGF 090547
FFWFGF
MNC027-NDC017-077-091200-
/O.NEW.KFGF.FF.W.0002.110509T0547Z-110509T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1242 AM CDT MON MAY 9 2011

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHWESTERN CLAY COUNTY IN NORTHWEST MINNESOTA...
  SOUTHEASTERN CASS COUNTY IN SOUTHEAST NORTH DAKOTA...
  NORTH CENTRAL RICHLAND COUNTY IN SOUTHEAST NORTH DAKOTA...

* UNTIL 700 AM CDT

* AT 1242 AM CDT...WEATHER SERVICE DOPPLER RADAR INDICATED   
  THUNDERSTORMS WITH VERY HEAVY RAINFALL IN THE WALCOTT AND 
  CHRISTINE AREAS OF RICHLAND AND CLAY COUNTIES. DOPPLER RADAR
  INDICATES 2 TO 4 INCHES OF RAIN HAVE FALLEN IN THE WALCOTT AREA
  SINCE AROUND 10 PM SUNDAY EVENING WITH ADDITIONAL STRONG
  THUNDERSTORMS DEVELOPING TO THE SOUTHWEST.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  CHRISTINE...COMSTOCK...HICKSON AND WALCOTT.

OVERLAND AND RIVER FLOODING FROM THE SPRING SNOWMELT CONTINUES IN 
THESE AREAS AND WILL BE EXACERBATED BY THIS HEAVY RAINFALL. FLOODING 
IN URBAN AND RURAL AREAS WILL LIKELY INCREASE AS DRAINAGE SYSTEMS 
ALREADY STRESSED BY THE FLOODING ARE OVERWHELMED AGAIN.

THE FOLLOWING STREAMS ARE INCLUDED IN THE WARNING...RED RIVER OF THE
NORTH...WILD RICE RIVER AND PITCAIRN CREEK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT DRIVE YOUR
VEHICLE INTO WATER OF UNKNOWN DEPTH. ONE OR TWO FEET OF WATER WILL
FLOAT MOST CARS DOWNSTREAM.

TURN AROUND DONT DROWN. AVOID DRIVING ON FLOODED ROADS. MOST FLOOD
RELATED DEATHS OCCUR IN AUTOMOBILES.

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.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 4648 9716 4675 9685 4666 9669 4662 9673
      4661 9677 4659 9676 4639 9697

$$

EWENS
2 follow-up statements
865 
WGUS73 KFGF 090752
FFSFGF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
251 AM CDT MON MAY 9 2011

MNC027-NDC017-077-091200-
/O.CON.KFGF.FF.W.0002.000000T0000Z-110509T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLAY MN-RICHLAND ND-CASS ND-
251 AM CDT MON MAY 9 2011

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 700 AM CDT FOR
SOUTHWESTERN CLAY COUNTY IN NORTHWEST MINNESOTA...AND SOUTHEASTERN
CASS AND NORTH CENTRAL RICHLAND COUNTIES IN SOUTHEAST NORTH DAKOTA...

AT 245 AM CDT...CLAY COUNTY MINNESOTA LAW ENFORCEMENT OFFICIALS 
REPORTED VERY HEAVY RAINS IN THE COMSTOCK AND RUSTAD AREAS OF 
SOUTHWEST CLAY COUNTY. THEY REPORTED SOME ADDITIONAL FLOODING DUE TO 
THE HEAVY RAINS. THE EXTENT OF THIS ADDITIONAL FLOODING IS DIFFICULT 
TO ASSESS AT THIS TIME DUE TO DARKNESS. AROUND 200 AM THE RICHLAND 
COUNTY LAW ENFORCEMENT REPORTED VERY HEAVY RAINS WITH SOME 
ADDITIONAL FLOODING NORTH OF WALCOTT TO THE RICHLAND/CASS COUNTY 
LINE.

DOPPLER RADAR ESTIMATES SHOW THAT 2 TO 4 INCHES OF RAIN HAD FALLEN 
FROM THE HICKSON AND COMSTOCK AREAS TO BETWEEN KINDRED AND WALCOTT. 
THE STRONG THUNDERSTORMS RESPONSIBLE FOR THE EXCESSIVE RAINS HAVE 
MOVED NORTHEAST OF THE WARNING AREA AND WEAKENED...BUT RUNOFF WILL 
CONTINUE FOR SEVERAL MORE HOURS CAUSING FLOODING.

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
CHRISTINE...COMSTOCK...HICKSON AND WALCOTT.

MINOR RIVER RISES HAVE BEEN OBSERVED ON THE WILD RICE NEAR SAINT 
BENEDICT NORTH DAKOTA. 

THE FOLLOWING STREAMS ARE INCLUDED IN THE WARNING...RED RIVER OF THE
NORTH...WILD RICE RIVER AND PITCAIRN CREEK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT DRIVE YOUR
VEHICLE INTO WATER OF UNKNOWN DEPTH. ONE OR TWO FEET OF WATER WILL
FLOAT MOST CARS DOWNSTREAM.

TURN AROUND DONT DROWN. AVOID DRIVING ON FLOODED ROADS. MOST FLOOD
RELATED DEATHS OCCUR IN AUTOMOBILES.

&&

LAT...LON 4648 9716 4675 9685 4666 9669 4662 9673
      4661 9677 4659 9676 4639 9697

$$

EWENS
993 
WGUS73 KFGF 091144
FFSFGF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
645 AM CDT MON MAY 9 2011

MNC027-NDC017-077-091200-
/O.CON.KFGF.FF.W.0002.000000T0000Z-110509T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLAY MN-RICHLAND ND-CASS ND-
645 AM CDT MON MAY 9 2011

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 700 AM CDT FOR
SOUTHWESTERN CLAY COUNTY IN NORTHWEST MINNESOTA...AND SOUTHEASTERN
CASS AND NORTH CENTRAL RICHLAND COUNTIES IN SOUTHEAST NORTH DAKOTA...

THE HEAVY RAINS THAT FELL IN NORTHEAST RICHLAND...EXTREME SOUTHEAST 
CASS AND SOUTHWEST CLAY COUNTIES OVERNIGHT HAVE MOVED OUT OF THE 
AREA. DOPPLER RADAR REPORTS SHOW THAT 2 TO 4 INCHES OF RAIN FELL IN 
THE WALCOTT...CHRISTINE AND COMSTOCK AREAS OVERNIGHT. 

PRELIMINARY LAW ENFORCEMENT REPORTS SUGGESTED THERE WAS FLOODING IN 
THE COMSTOCK...RUSTAD AND WALCOTT AREAS OVERNIGHT. THERE WERE MINOR 
RISES OBSERVED ON AREA RIVERS AS WELL. THE WILD RICE RIVER NEAR 
SAINT BENEDICT ROSE ABOUT 0.2 FOOT WHILE THE SOUTH BRANCH OF THE 
BUFFALO RIVER NEAR SABIN ROSE ABOUT 0.5 FOOT OVERNIGHT. 

BASED ON THESE RISES AND LAW ENFORCEMENT REPORTS THERE MAY YET BE 
AREAS WHERE WATER IS PONDED DUE TO POOR DRAINAGE. HOWEVER...THE 
THREAT TO LIFE AND PROPERTY IN THE WARNING AREA HAS PASSED.

THEREFORE THE FLASH FLOOD WARNING WILL BE ALLOWED TO EXPIRE AT 7 AM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TURN AROUND DONT DROWN. AVOID DRIVING ON FLOODED ROADS. MOST FLOOD 
RELATED DEATHS OCCUR IN AUTOMOBILES.

&&

LAT...LON 4648 9716 4675 9685 4666 9669 4662 9673
      4661 9677 4659 9676 4639 9697

$$

EWENS

The office that day

Everything else NWS Grand Forks, ND issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 9, 3:31 AM CDTAreal Flood AdvisoryFGFBarnes8 hr
May 9, 2:05 AM CDTSevere Thunderstorm WarningFGFGrant55 min

Nearby

Flash Flood Warnings in North Dakota, 2011Flash 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.