Alert archive / South Dakota / Flash Flood Warnings in 2019

Flash Flood Warning 21, NWS Sioux Falls, SD

September 11, 20196 counties in South Dakota

NWS Sioux Falls, SD issued this flash flood warning at Sep 11, 2019, 12:24 AM CDT for 6 counties in South Dakota. 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: Sep 11, 2019, 12:24 AM CDT (05:24 UTC)
Expired: Sep 11, 2019, 6:30 AM CDT
In force: 6 hr
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Flood severity: None

Counties Clay County, SD, Hutchinson County, SD, Lincoln County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 52 km from the middle of the area, began a volume at 05:25 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 00:00Z, 5.4 hours before the alert went out and 215 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: 2988 J/kg
Mixed-layer CIN: -12 J/kg
Mixed-layer LCL: 1146 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 86 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 6.1

Open this sounding in Storm Lab

The text

As transmitted.

407 
WGUS53 KFSD 110524
FFWFSD
SDC027-067-083-125-127-135-111130-
/O.NEW.KFSD.FF.W.0021.190911T0524Z-190911T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Sioux Falls SD
1224 AM CDT Wed Sep 11 2019

The National Weather Service in Sioux Falls has issued a

* Flash Flood Warning for...
  Northern Clay County in southeastern South Dakota...
  Southwestern Lincoln County in southeastern South Dakota...
  Northeastern Yankton County in southeastern South Dakota...
  Southern Turner County in southeastern South Dakota...
  Northwestern Union County in southeastern South Dakota...
  Eastern Hutchinson County in southeastern South Dakota...

* Until 630 AM CDT Wednesday.

* At 1224 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...
  Canton, Beresford, Lennox, Centerville, Worthing, Viborg, Irene,
  Hurley, Mayfield, Davis and Newton Hills State Park.

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 4304 9733 4327 9747 4336 9706 4336 9658
      4303 9656

$$

Maldonado

2 follow-up statements

525 
WGUS73 KFSD 111025
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
525 AM CDT Wed Sep 11 2019

SDC027-067-083-125-127-135-111130-
/O.CON.KFSD.FF.W.0021.000000T0000Z-190911T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clay SD-Lincoln SD-Yankton SD-Turner SD-Union SD-Hutchinson SD-
525 AM CDT Wed Sep 11 2019

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 AM CDT FOR
NORTHERN CLAY...SOUTHWESTERN LINCOLN...NORTHEASTERN YANKTON...
SOUTHERN TURNER...NORTHWESTERN UNION AND EASTERN HUTCHINSON
COUNTIES...

At 523 AM CDT, Doppler radar indicated thunderstorms had produced 
heavy rain across the warned area, with radar estimates of rainfall 
in excess of 3 to 4 inches. An additional area of light to moderate 
rain will be moving across the area, which may exacerbate any 
ongoing flooding.  

Some locations that will experience flooding include...
Canton, Beresford, Lennox, Centerville, Worthing, Viborg, Irene,
Hurley, Mayfield, Davis and Newton Hills State Park.

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 4304 9733 4327 9747 4336 9706 4336 9658
      4303 9656

$$

JH

842 
WGUS73 KFSD 111129
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
629 AM CDT Wed Sep 11 2019

SDC027-067-083-125-127-135-111139-
/O.EXP.KFSD.FF.W.0021.000000T0000Z-190911T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clay SD-Lincoln SD-Yankton SD-Turner SD-Union SD-Hutchinson SD-
629 AM CDT Wed Sep 11 2019

...THE FLASH FLOOD WARNING FOR NORTHERN CLAY...SOUTHWESTERN
LINCOLN...NORTHEASTERN YANKTON...SOUTHERN TURNER...NORTHWESTERN UNION
AND EASTERN HUTCHINSON COUNTIES WILL EXPIRE AT 630 AM CDT
WEDNESDAY...

Although heavy rain has has ended, Doppler radar indicates that 
earlier thunderstorms have produced an estimated three to six inches 
of rain over the past twelve hours. Therefore, an areal flood 
warning has been issued to replace this warning. 

Widespread ponding of water and flooding issues likely continue in 
the warned area. Light rain and isolated thunderstorms will continue 
through the morning hours, and water will be slow to drain. Please 
continue to heed any remaining road closures.

LAT...LON 4304 9733 4327 9747 4336 9706 4336 9658
      4303 9656

$$

JH

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 10, 7:24 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule, Charles Mix, Douglas, Gregory	36 min
Sep 10, 7:46 PM CDT	Severe Thunderstorm Warning	FSD	Bon Homme, Charles Mix, Douglas, Hutchinson	44 min
Sep 10, 7:58 PM CDT	Tornado Warning	FSD	Charles Mix, Douglas	32 min
Sep 10, 8:01 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule, Charles Mix, Davison, Douglas, Gregory	44 min
Sep 10, 8:07 PM CDT	Tornado Warning	FSD	Bon Homme, Charles Mix	38 min
Sep 10, 8:41 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Charles Mix, Davison, Douglas, Hutchinson	49 min
Sep 10, 8:52 PM CDT	Tornado Warning	FSD	Aurora, Davison	23 min
Sep 10, 8:52 PM CDT	Tornado Warning	FSD	Bon Homme, Hutchinson	38 min
Sep 10, 9:13 PM CDT	Severe Thunderstorm Warning	FSD	Charles Mix, Douglas, Gregory	47 min
Sep 10, 9:28 PM CDT	Severe Thunderstorm Warning	FSD	Davison, Hanson, Miner, Sanborn	29 min
Sep 10, 9:29 PM CDT	Flash Flood Warning	FSD	Bon Homme, Charles Mix, Davison, Douglas, Hanson, Hutchinson	6 hr
Sep 10, 9:36 PM CDT	Tornado Warning	FSD	Hutchinson	24 min
Sep 10, 9:46 PM CDT	Severe Thunderstorm Warning	FSD	Bon Homme, Charles Mix, Douglas, Hutchinson	44 min
Sep 10, 9:56 PM CDT	Tornado Warning	FSD	Hanson, Hutchinson, McCook	34 min
Sep 10, 10:22 PM CDT	Flash Flood Warning	FSD	Hanson, Hutchinson, McCook, Turner	5 hr
Sep 10, 10:22 PM CDT	Severe Thunderstorm Warning	FSD	Bon Homme, Hanson, Hutchinson, McCook, Yankton	53 min
Sep 10, 10:42 PM CDT	Tornado Warning	FSD	Hutchinson, McCook, Turner	33 min
Sep 10, 10:47 PM CDT	Severe Thunderstorm Warning	FSD	Clay, Hutchinson, Lincoln, McCook, Minnehaha, Turner and 1 more	43 min
Sep 10, 10:53 PM CDT	Tornado Warning	FSD	McCook, Minnehaha, Turner	24 min
Sep 10, 11:04 PM CDT	Tornado Warning	FSD	Lincoln, Turner	26 min
Sep 10, 11:13 PM CDT	Severe Thunderstorm Warning	FSD	Lincoln, Minnehaha, Turner	47 min
Sep 10, 11:26 PM CDT	Flash Flood Warning	FSD	Lake, Lincoln, McCook, Miner, Minnehaha, Moody and 1 more	3 hr
Sep 10, 11:27 PM CDT	Tornado Warning	FSD	Lincoln, Minnehaha	33 min
Sep 10, 11:54 PM CDT	Tornado Warning	FSD	Minnehaha	13 min
Sep 10, 11:59 PM CDT	Severe Thunderstorm Warning	FSD	Minnehaha	46 min
Sep 11, 12:24 AM CDT	Flash Flood Warning	FSD	Brookings, Kingsbury, Lake, Moody	6 hr
Sep 11, 12:55 AM CDT	River Flood Warning	FSD	Minnehaha, Moody	21 days
Sep 11, 12:55 AM CDT	River Flood Warning	FSD	Minnehaha	21 days
Sep 11, 1:03 AM CDT	Flash Flood Warning	FSD	Lincoln, Minnehaha	6 hr
Sep 11, 2:17 AM CDT	Flash Flood Warning	FSD	Lake, Lincoln, McCook, Miner, Minnehaha, Moody and 1 more	4 hr
Sep 11, 3:14 AM CDT	Flash Flood Warning	FSD	Union	4 hr
Sep 11, 3:31 AM CDT	Areal Flood Warning	FSD	Bon Homme, Brookings, Charles Mix, Clay, Douglas, Hanson and 9 more	18 hr
Sep 11, 4:07 AM CDT	Flash Flood Watch	FSD	Aurora, Beadle, Bon Homme, Brookings, Brule, Charles Mix and 18 more	26 hr
Sep 11, 8:01 AM CDT	River Flood Warning	FSD	Minnehaha	29 days
Sep 11, 8:01 AM CDT	River Flood Warning	FSD	Moody	21 days
Sep 11, 9:10 AM CDT	River Flood Warning	FSD	Lincoln, Minnehaha	14 days
Sep 11, 9:10 AM CDT	River Flood Warning	FSD	Union	16 days
Sep 11, 9:10 AM CDT	River Flood Warning	FSD	Union	21 days
Sep 11, 9:10 AM CDT	River Flood Warning	FSD	Minnehaha	60 hr
Sep 11, 9:21 AM CDT	River Flood Warning	FSD	Yankton	24 days
Sep 11, 9:21 AM CDT	River Flood Warning	FSD	Turner	6 days
Sep 11, 9:21 AM CDT	River Flood Warning	FSD	Turner	21 days
Sep 11, 9:21 AM CDT	River Flood Warning	FSD	Turner	21 days
Sep 11, 9:21 AM CDT	River Flood Warning	FSD	Clay	8 days
Sep 11, 9:21 AM CDT	River Flood Warning	FSD	Clay	21 days
Sep 11, 9:21 AM CDT	River Flood Warning	FSD	Moody	21 days
Sep 11, 10:42 AM CDT	River Flood Warning	FSD	Minnehaha, Moody	21 days
Sep 11, 3:41 PM CDT	River Flood Warning	FSD	Minnehaha, Moody	13 days
Sep 11, 3:44 PM CDT	River Flood Warning	FSD	Moody	21 days

Nearby

Flash Flood Warnings in South Dakota, 2019 Every flash flood warning in 2019

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.