Alert archive / South Dakota / Flash Flood Warnings in 2016

Flash Flood Warning 27, NWS Sioux Falls, SD

September 7, 2016Plymouth County, Sioux County, Iowa; Dixon County, Nebraska; 4 counties in South Dakota

NWS Sioux Falls, SD issued this flash flood warning at Sep 7, 2016, 1:45 AM CDT for Plymouth County, Sioux County, Iowa; Dixon County, Nebraska; 4 counties in South Dakota. It was in force for 4 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
Sep 7, 2016, 1:45 AM CDT (06:45 UTC)
Expired
Sep 7, 2016, 5:45 AM CDT
In force
4 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

Counties Plymouth County, IA, Sioux County, IA, Dixon County, NE, Clay County, SD, Lincoln County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 88 km from the middle of the area, began a volume at 06:49 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
Sep 7, 3:15 AM CDTFLASH FLOODVermillion, SDPOLICE PATROLS REPORTED THAT SOME OF THE INTERSECTIONS ACROSS TOWN WERE 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, 6.8 hours before the alert went out and 173 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, Omaha, NE at 00:00Z on 2016-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2597 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, Omaha, NE at 00:00Z on 2016-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 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
2597 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
1252 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
1.5
Supercell composite
9.8

Open this sounding in Storm Lab

The text

As transmitted.

419 
WGUS53 KFSD 070645
FFWFSD
IAC149-167-NEC051-SDC027-083-127-135-071045-
/O.NEW.KFSD.FF.W.0027.160907T0645Z-160907T1045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
145 AM CDT WED SEP 7 2016

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SIOUX COUNTY IN NORTHWESTERN IOWA...
  PLYMOUTH COUNTY IN NORTHWESTERN IOWA...
  NORTHERN DIXON COUNTY IN NORTHEASTERN NEBRASKA...
  UNION COUNTY IN SOUTHEASTERN SOUTH DAKOTA...
  SOUTHEASTERN YANKTON COUNTY IN SOUTHEASTERN SOUTH DAKOTA...
  CLAY COUNTY IN SOUTHEASTERN SOUTH DAKOTA...
  SOUTHEASTERN LINCOLN COUNTY IN SOUTHEASTERN SOUTH DAKOTA...

* UNTIL 545 AM CDT

* AT 143 AM CDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING
  HEAVY RAIN ACROSS THE WARNED AREA. UP TO TWO INCHES OF RAIN HAVE
  ALREADY FALLEN. FLASH FLOODING IS EXPECTED TO BEGIN SHORTLY.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  VERMILLION...LE MARS...SIOUX CENTER...ORANGE CITY...HAWARDEN...
  BERESFORD...HULL...ELK POINT...REMSEN...AKRON...ALTON...ALCESTER...
  MERRILL...IRETON...JEFFERSON...NEWCASTLE...WAKONDA...HUDSON...
  MAURICE AND MECKLING.

ADDITIONAL RAINFALL AMOUNTS OF 2 TO 3 INCHES ARE POSSIBLE IN THE
WARNED AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TURN AROUND...DON'T DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING.

&&

LAT...LON 4276 9702 4277 9705 4277 9713 4280 9716
      4281 9721 4285 9722 4285 9727 4297 9731
      4321 9608 4274 9586 4251 9702

$$

WEISSER
2 follow-up statements
382 
WGUS73 KFSD 070832
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
332 AM CDT WED SEP 7 2016

IAC149-167-NEC051-SDC027-083-127-135-071045-
/O.CON.KFSD.FF.W.0027.000000T0000Z-160907T1045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SIOUX IA-PLYMOUTH IA-DIXON NE-UNION SD-YANKTON SD-CLAY SD-LINCOLN SD-
332 AM CDT WED SEP 7 2016

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 AM CDT FOR
SIOUX...PLYMOUTH...NORTHERN DIXON...UNION...SOUTHEASTERN YANKTON...
CLAY AND SOUTHEASTERN LINCOLN COUNTIES...

AT 331 AM CDT...DOPPLER RADAR INDICATED THUNDERSTORMS PRODUCING
HEAVY RAIN ACROSS THE WARNED AREA. THREE TO FOUR INCHES OF RAIN HAVE
ALREADY FALLEN. FLASH FLOODING IS OCCURRING OR IS EXPECTED TO BEGIN
SHORTLY.

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
VERMILLION...LE MARS...SIOUX CENTER...ORANGE CITY...HAWARDEN...
BERESFORD...HULL...ELK POINT...REMSEN...AKRON...ALTON...ALCESTER...
MERRILL...IRETON...JEFFERSON...NEWCASTLE...WAKONDA...HUDSON...
MAURICE AND MECKLING.

AT 315 AM CDT...VERMILLION POLICE DEPARTMENT REPORTED THAT SOME OF
THE INTERSECTIONS WERE FLOODED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TURN AROUND...DON'T DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING.

&&

LAT...LON 4276 9702 4277 9705 4277 9713 4280 9716
      4281 9721 4285 9722 4285 9727 4297 9731
      4321 9608 4274 9586 4251 9702

$$

WEISSER
671 
WGUS73 KFSD 071022
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
522 AM CDT WED SEP 7 2016

IAC149-167-NEC051-SDC027-083-127-135-071032-
/O.CAN.KFSD.FF.W.0027.000000T0000Z-160907T1045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SIOUX IA-PLYMOUTH IA-DIXON NE-UNION SD-YANKTON SD-CLAY SD-LINCOLN SD-
522 AM CDT WED SEP 7 2016

...THE FLASH FLOOD WARNING FOR SIOUX...PLYMOUTH...NORTHERN DIXON...
UNION...SOUTHEASTERN YANKTON...CLAY AND SOUTHEASTERN LINCOLN COUNTIES
IS CANCELLED...

FLOOD WATERS HAVE RECEDED. FLOODING IS NO LONGER EXPECTED TO POSE A
THREAT. PLEASE CONTINUE TO HEED ANY REMAINING ROAD CLOSURES.

LAT...LON 4276 9702 4277 9705 4277 9713 4280 9716
      4281 9721 4285 9722 4285 9727 4297 9731
      4321 9608 4274 9586 4251 9702

$$

WEISSER

Nearby

Flash Flood Warnings in South Dakota, 2016Flash Flood Warnings in Iowa, 2016Flash Flood Warnings in Nebraska, 2016Every flash flood warning in 2016

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.