Alert archive / Nebraska / Flash Flood Warnings in 2014

Flash Flood Warning 13, NWS Sioux Falls, SD

June 14, 2014Dakota County, Dixon County, Nebraska; Union County, South Dakota; Plymouth County, Woodbury County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at Jun 14, 2014, 8:20 PM CDT for Dakota County, Dixon County, Nebraska; Union County, South Dakota; Plymouth County, Woodbury County, Iowa. It was in force for 5 hr. 2 reports 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: Jun 14, 2014, 8:20 PM CDT (01:20 UTC)
Expired: Jun 15, 2014, 1:30 AM CDT
In force: 5 hr
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Flood severity: None

Counties Plymouth County, IA, Woodbury County, IA, Dakota County, NE, Dixon County, NE, Union County, SD

The radar

The Omaha radar (KOAX), 126 km from the middle of the area, began a volume at 01:21 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

Time	Report	Where	Remark
Jun 14, 8:45 PM CDT	FLASH FLOOD	Sioux City, IA	1.99 INCHES OF RAIN IN 30 MINUTES MAN HOLE COVERS BLOWING OFF
Jun 14, 10:00 PM CDT	FLASH FLOOD	Sergeant Bluff, IA	ROADS IN SERGEANT BLUFF FLOODED

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

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 1.3 hours before the alert went out and 126 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2298 J/kg
Mixed-layer CIN: -8 J/kg
Mixed-layer LCL: 1112 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 134 m²/s²
0-3 km storm-relative helicity: 352 m²/s²
Significant tornado parameter: 3.3
Supercell composite: 23.5

Open this sounding in Storm Lab

The text

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

966 
WGUS53 KFSD 150120
FFWFSD
IAC149-193-NEC043-051-SDC127-150630-
/O.NEW.KFSD.FF.W.0013.140615T0120Z-140615T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
820 PM CDT SAT JUN 14 2014

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  DAKOTA COUNTY IN NORTHEAST NEBRASKA
  DIXON COUNTY IN NORTHEAST NEBRASKA
  NORTHWESTERN WOODBURY COUNTY IN WEST CENTRAL IOWA
  SOUTHERN UNION COUNTY IN SOUTHEAST SOUTH DAKOTA
  WESTERN PLYMOUTH COUNTY IN NORTHWEST IOWA

* UNTIL 130 AM CDT

* AT 815 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. 
  UP TO 3 INCHES OF RAINFALL WAS REPORTED NEAR CONCORD NEBRASKA
  THROUGH 800 PM. WITH PERIODIC THUNDERSTORMS EXPECTED OVER THE
  NEXT SEVERAL HOURS...SOME WITH INSTANTANEOUS RAINFALL RATES OF
  3 TO 4 INCHES PER HOUR...THERE WILL LIKELY BE FLOODING OF SMALL
  STREAMS AND URBAN AREAS. ADDITIONAL RAINFALL OF 1 TO 3 INCHES
  IS LIKELY THROUGHOUT THE WARNED AREA.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  PONCA...SIOUX CITY...ALLEN...CONCORD...DAKOTA CITY...DIXON...ELK
  POINT...HUBBARD...JACKSON...JEFFERSON...MARTINSBURG...NEWCASTLE...
  NORTH SIOUX CITY...SERGEANT BLUFF...SOUTH SIOUX CITY AND STONE
  STATE PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.

&&

LAT...LON 4227 9703 4233 9703 4261 9702 4285 9637
      4236 9629 4226 9696 4226 9701

$$

CHAPMAN

2 follow-up statements

378 
WGUS73 KFSD 150212
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
912 PM CDT SAT JUN 14 2014

IAC149-193-NEC043-051-SDC127-150630-
/O.CON.KFSD.FF.W.0013.000000T0000Z-140615T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PLYMOUTH IA-WOODBURY IA-DAKOTA NE-DIXON NE-UNION SD-
912 PM CDT SAT JUN 14 2014

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHERN UNION...
DIXON...DAKOTA...NORTHWESTERN WOODBURY AND WESTERN PLYMOUTH COUNTIES
UNTIL 130 AM CDT...

AT 845 PM CDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA.
VERY HEAVY RAIN WAS REPORTED WITH MANHOLE COVERS WERE BEING BLOWN 
OFF IN DOWNTOWN LOCATIONS AT 845 PM CDT. A TRAINED SPOTTER REPORTED 
1.99 INCHES OF RAIN IN A HALF HOUR 2 MILES NORTH OF THE SIOUX 
GATEWAY AIRPORT. ADDITIONAL THUNDERSTORMS WILL BRING ONE TO THREE 
INCHES OF RAINFALL THROUGH MIDNIGHT.

SLOW MOVING THUNDERSTORMS ARE PRODUCING VERY HEAVY RAINFALL IN THE
WARNED AREA. RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH
FLOODING TO OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING
INCLUDE...PONCA...SIOUX CITY...ALLEN...CONCORD...DAKOTA CITY...
DIXON...ELK POINT...HUBBARD...JACKSON...JEFFERSON...MARTINSBURG...
NEWCASTLE...NORTH SIOUX CITY...SERGEANT BLUFF...SOUTH SIOUX CITY AND
STONE STATE PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLOODING OF SMALL CREEKS
AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY ROADS
AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW LYING
AREAS ARE ALSO SUBJECT TO FLOODING.

&&

LAT...LON 4227 9703 4233 9703 4261 9702 4285 9637
      4236 9629 4226 9696 4226 9701

$$

CHAPMAN

877 
WGUS73 KFSD 150643
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
143 AM CDT SUN JUN 15 2014

IAC149-193-NEC043-051-SDC127-150700-
/O.EXP.KFSD.FF.W.0013.000000T0000Z-140615T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PLYMOUTH IA-WOODBURY IA-DAKOTA NE-DIXON NE-UNION SD-
143 AM CDT SUN JUN 15 2014

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTHERN UNION...
DIXON...DAKOTA...NORTHWESTERN WOODBURY AND WESTERN PLYMOUTH COUNTIES 
HAS BEEN ALLOWED TO EXPIRE...AND HAD BEEN REPLACED BY AN AREAL FLOOD 
WARNING...

RAINFALL CONTINUES AT A STEADY RATE AT 130 AM...WITH HOURLY RATES OF 
A THIRD TO THREE QUARTERS OF AN INCH.  THIS RAINFALL WILL CONTINUE
TO WORSEN ONGOING FLOODING ACROSS NORTHEAST NEBRASKA...EXTREME 
SOUTHEAST SOUTH DAKOTA...AND SOUTHERN PORTIONS OF NORTHWEST IOWA.
TRAVEL IS NOT ADVISED IN MANY LOCATIONS DUE TO FLOODING OF RURAL 
ROADS AND URBAN AREAS...THE DEGREE OF WHICH IT IS IMPOSSIBLE TO 
DIAGNOSE AT NIGHT. IF FLOODING HAS BEEN OBSERVED...PLEASE REPORT IT 
TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4227 9703 4233 9703 4261 9702 4285 9637
      4236 9629 4226 9696 4226 9701

$$

CHAPMAN

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 14, 7:05 PM CDT	Severe Thunderstorm Warning	FSD	Dixon	40 min
Jun 14, 7:42 PM CDT	Severe Thunderstorm Warning	FSD	Dixon	48 min
Jun 14, 10:34 PM CDT	Severe Thunderstorm Warning	FSD	Dakota, Dixon	41 min
Jun 14, 11:00 PM CDT	Severe Thunderstorm Warning	FSD	Dakota	45 min
Jun 15, 12:35 AM CDT	Flash Flood Warning	FSD	Dakota	115 min
Jun 15, 1:31 AM CDT	Areal Flood Warning	FSD	Dakota, Dixon	12 hr
Jun 14, 7:10 PM CDT	Severe Thunderstorm Warning	FSD	Lincoln	50 min
Jun 14, 8:55 PM CDT	Flash Flood Warning	FSD	Lincoln, Minnehaha	3 hr
Jun 14, 10:17 PM CDT	Flash Flood Warning	FSD	Lincoln, Minnehaha	4 hr
Jun 14, 10:36 PM CDT	River Flood Warning	FSD	Minnehaha	7 days
Jun 15, 2:05 AM CDT	Areal Flood Warning	FSD	Lincoln, Minnehaha	12 hr
Jun 15, 2:32 AM CDT	River Flood Warning	FSD	Moody	24 hr
Jun 15, 2:32 AM CDT	River Flood Warning	FSD	Minnehaha	46 hr
Jun 14, 7:50 PM CDT	Severe Thunderstorm Warning	FSD	O'Brien, Sioux	40 min
Jun 14, 9:35 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee, Ida, Plymouth, Woodbury	55 min
Jun 14, 9:44 PM CDT	Flash Flood Warning	FSD	Cherokee, Ida, O'Brien, Plymouth, Sioux, Woodbury	5 hr
Jun 15, 12:23 AM CDT	River Flood Warning	FSD	Lyon	5 days
Jun 15, 5:12 AM CDT	River Flood Warning	FSD	Lyon, Sioux	6 days
Jun 15, 5:12 AM CDT	River Flood Warning	FSD	Clay	13 days
Jun 15, 5:12 AM CDT	River Flood Warning	FSD	Monona, Woodbury	55 hr
Jun 15, 8:18 AM CDT	Areal Flood Warning	FSD	Ida	12 hr

Nearby

Flash Flood Warnings in Nebraska, 2014 Flash Flood Warnings in Iowa, 2014 Flash Flood Warnings in South Dakota, 2014 Every flash flood warning in 2014

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.