Alert archive / Iowa / Flash Flood Warnings in 2018

Flash Flood Warning 4, NWS Sioux Falls, SD

June 14, 2018Buena Vista County, Clay County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at Jun 14, 2018, 7:37 AM CDT for Buena Vista County, Clay County, Iowa. It was in force for 3 hr. 3 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, 2018, 7:37 AM CDT (12:37 UTC)
Expired
Jun 14, 2018, 10:30 AM CDT
In force
3 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

Counties Buena Vista County, IA, Clay County, IA

The radar

The Sioux Falls radar (KFSD), 152 km from the middle of the area, began a volume at 12:40 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
Jun 14, 8:40 AM CDTHEAVY RAIN 2.561 N Gillett Grove, IA
Jun 14, 8:54 AM CDTHEAVY RAIN 3.842 N Sioux Rapids, IA
Jun 14, 9:12 AM CDTFLASH FLOODWebb, IAWATER OVER ROADWAYS. REPORTED 5.0 INCHES OF RAIN.

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 12:00Z, 0.6 hours before the alert went out and 207 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 2018-06-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1543 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 2018-06-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 219 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
1543 J/kg
Mixed-layer CIN
-305 J/kg
Mixed-layer LCL
1231 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
219 m²/s²
0-3 km storm-relative helicity
312 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.2

Open this sounding in Storm Lab

The text

As transmitted.

116 
WGUS53 KFSD 141237
FFWFSD
IAC021-041-141530-
/O.NEW.KFSD.FF.W.0004.180614T1237Z-180614T1530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Sioux Falls SD
737 AM CDT THU JUN 14 2018

The National Weather Service in Sioux Falls has issued a

* Flash Flood Warning for...
  Northeastern Buena Vista County in northwestern Iowa...
  Southeastern Clay County in northwestern Iowa...

* Until 1030 AM CDT.

* At 736 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 as 
  rain continues to fall over the next hour.

* Some locations that will experience flooding include...
  Sioux Rapids, Marathon, Linn Grove, Webb, Greenville, Rossie and
  Gillett Grove.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 4283 9509 4287 9528 4297 9528 4305 9510
      4307 9491 4283 9491

$$

VandenBoogart
2 follow-up statements
979 
WGUS73 KFSD 141330
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
830 AM CDT THU JUN 14 2018

IAC021-041-141530-
/O.CON.KFSD.FF.W.0004.000000T0000Z-180614T1530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Buena Vista IA-Clay IA-
830 AM CDT THU JUN 14 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 AM CDT FOR
NORTHEASTERN BUENA VISTA AND SOUTHEASTERN CLAY COUNTIES...

At 829 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Three to five inches of rain have 
fallen. Flash flooding is expected.

Some locations that will experience flooding include...
Sioux Rapids, Marathon, Linn Grove, Webb, Greenville, Rossie and
Gillett Grove.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 4283 9509 4287 9528 4297 9528 4305 9510
      4307 9491 4283 9491

$$

BT
189 
WGUS73 KFSD 141524
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
1024 AM CDT THU JUN 14 2018

IAC021-041-141534-
/O.EXP.KFSD.FF.W.0004.000000T0000Z-180614T1530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Buena Vista IA-Clay IA-
1024 AM CDT THU JUN 14 2018

...THE FLASH FLOOD WARNING FOR NORTHEASTERN BUENA VISTA AND
SOUTHEASTERN CLAY COUNTIES WILL EXPIRE AT 1030 AM CDT...

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

LAT...LON 4283 9509 4287 9528 4297 9528 4305 9510
      4307 9491 4283 9491

$$

BT

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 14, 3:15 AM CDTSevere Thunderstorm WarningFSDCherokee, Plymouth, Woodbury30 min
Jun 14, 3:41 AM CDTSevere Thunderstorm WarningFSDCherokee, Plymouth34 min
Jun 14, 4:18 AM CDTSevere Thunderstorm WarningFSDClay, O'Brien27 min
Jun 14, 5:32 AM CDTSevere Thunderstorm WarningFSDClay, O'Brien28 min
Jun 14, 6:20 AM CDTSevere Thunderstorm WarningFSDLyon, Osceola12 min
Jun 14, 7:01 AM CDTFlash Flood WarningFSDLyon, O'Brien, Osceola3 hr
Jun 14, 10:08 AM CDTRiver Flood WarningFSDBuena Vista, Clay38 days
Jun 14, 10:41 AM CDTAreal Flood WarningFSDO'Brien, Sioux24 hr
Jun 14, 2:50 PM CDTHeat AdvisoryFSDBuena Vista, Cherokee, Clay, Dickinson, Ida, O'Brien and 4 more3 days

Nearby

Flash Flood Warnings in Iowa, 2018Every flash flood warning in 2018

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.