Alert archive / Iowa / Flash Flood Warnings in 2017

Flash Flood Warning 1, NWS Sioux Falls, SD

June 29, 2017Plymouth County, Woodbury County, Iowa; Union County, South Dakota; Dakota County, Nebraska

NWS Sioux Falls, SD issued this flash flood warning at Jun 29, 2017, 4:47 PM CDT for Plymouth County, Woodbury County, Iowa; Union County, South Dakota; Dakota County, Nebraska. It was in force for 3 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
Jun 29, 2017, 4:47 PM CDT (21:47 UTC)
Expired
Jun 29, 2017, 7:45 PM CDT
In force
3 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

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

The radar

The Sioux Falls radar (KFSD), 128 km from the middle of the area, began a volume at 21:47 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

Omaha, NE (KOAX), launched 12:00Z, 9.8 hours before the alert went out and 129 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 12:00Z on 2017-06-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 712 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 12:00Z on 2017-06-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -19 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
712 J/kg
Mixed-layer CIN
-119 J/kg
Mixed-layer LCL
1324 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
-19 m²/s²
0-3 km storm-relative helicity
9 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted.

957 
WGUS53 KFSD 292147
FFWFSD
IAC149-193-NEC043-SDC127-300045-
/O.NEW.KFSD.FF.W.0001.170629T2147Z-170630T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Sioux Falls SD
447 PM CDT THU JUN 29 2017

The National Weather Service in Sioux Falls has issued a

* Flash Flood Warning for...
  Northwestern Woodbury County in west central Iowa...
  South central Plymouth County in northwestern Iowa...
  Northeastern Dakota County in northeastern Nebraska...
  Southeastern Union County in southeastern South Dakota...

* Until 745 PM CDT

* At 447 PM CDT, Doppler radar indicated heavy rain across the warned
  area. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Sioux City, South Sioux City, Sergeant Bluff, North Sioux City,
  Dakota City, Lawton and Bronson.

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.

&&

LAT...LON 4260 9617 4234 9609 4234 9644 4253 9653

$$

Schumacher
1 follow-up statement
949 
WGUS73 KFSD 300039
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
739 PM CDT THU JUN 29 2017

IAC149-193-NEC043-SDC127-300049-
/O.EXP.KFSD.FF.W.0001.000000T0000Z-170630T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Woodbury IA-Plymouth IA-Dakota NE-Union SD-
739 PM CDT THU JUN 29 2017

...THE FLASH FLOOD WARNING FOR NORTHWESTERN WOODBURY...SOUTH CENTRAL
PLYMOUTH...NORTHEASTERN DAKOTA AND SOUTHEASTERN UNION COUNTIES WILL
EXPIRE AT 745 PM CDT...

Flood waters have receded. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 4260 9617 4234 9609 4234 9644 4253 9653

$$

Weisser

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 29, 3:48 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury42 min
Jun 29, 4:08 PM CDTSevere Thunderstorm WarningFSDPlymouth52 min
Jun 29, 4:23 PM CDTTornado WarningFSDWoodbury37 min
Jun 29, 4:26 PM CDTSevere Thunderstorm WarningFSDWoodbury49 min
Jun 29, 4:46 PM CDTTornado WarningFSDWoodbury29 min
Jun 29, 4:54 PM CDTSevere Thunderstorm WarningFSDSioux51 min
Jun 29, 5:10 PM CDTSevere Thunderstorm WarningFSDWoodbury35 min
Jun 29, 5:29 PM CDTSevere Thunderstorm WarningFSDClay33 min
Jun 29, 5:30 PM CDTTornado WarningFSDWoodbury30 min
Jun 29, 5:43 PM CDTSevere Thunderstorm WarningFSDLyon, Sioux18 min
Jun 29, 5:59 PM CDTSevere Thunderstorm WarningFSDIda, Woodbury22 min
Jun 29, 6:27 PM CDTSevere Thunderstorm WarningFSDPlymouth, Sioux33 min
Jun 29, 3:22 PM CDTSevere Thunderstorm WarningFSDUnion53 min
Jun 29, 3:41 PM CDTSevere Thunderstorm WarningFSDCharles Mix, Douglas34 min
Jun 29, 3:47 PM CDTSevere Thunderstorm WarningFSDAurora, Douglas28 min
Jun 29, 3:57 PM CDTSevere Thunderstorm WarningFSDCharles Mix, Douglas33 min
Jun 29, 4:06 PM CDTSevere Thunderstorm WarningFSDCharles Mix, Douglas24 min
Jun 29, 4:15 PM CDTSevere Thunderstorm WarningFSDBon Homme, Charles Mix, Douglas, Hutchinson30 min
Jun 29, 4:16 PM CDTSevere Thunderstorm WarningFSDBon Homme, Charles Mix29 min
Jun 29, 4:40 PM CDTSevere Thunderstorm WarningFSDBon Homme, Charles Mix, Douglas, Hutchinson35 min
Jun 29, 5:01 PM CDTSevere Thunderstorm WarningFSDBon Homme, Hutchinson, Yankton29 min
Jun 29, 5:23 PM CDTSevere Thunderstorm WarningFSDBon Homme, Hutchinson, Turner, Yankton37 min
Jun 29, 5:39 PM CDTSevere Thunderstorm WarningFSDClay, Turner, Yankton36 min
Jun 29, 6:03 PM CDTSevere Thunderstorm WarningFSDClay, Union, Yankton27 min
Jun 29, 6:12 PM CDTTornado WarningFSDUnion18 min

Nearby

Flash Flood Warnings in Iowa, 2017Flash Flood Warnings in South Dakota, 2017Flash Flood Warnings in Nebraska, 2017Every flash flood warning in 2017

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.