Alert archive / South Dakota / Flash Flood Warnings in 2018

Flash Flood Warning 28, NWS Sioux Falls, SD

July 19, 2018Brookings County, South Dakota; Lincoln County, Minnesota

NWS Sioux Falls, SD issued this flash flood warning at Jul 19, 2018, 5:46 AM CDT for Brookings County, South Dakota; Lincoln County, Minnesota. 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: Jul 19, 2018, 5:46 AM CDT (10:46 UTC)
Expired: Jul 19, 2018, 9:15 AM CDT
In force: 3 hr
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Flood severity: None

Counties Lincoln County, MN, Brookings County, SD

The radar

The Sioux Falls radar (KFSD), 94 km from the middle of the area, began a volume at 10:48 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

Minneapolis, MN (KMPX), launched 00:00Z, 10.8 hours before the alert went out and 227 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1474 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 1 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

435 
WGUS53 KFSD 191046
FFWFSD
MNC081-SDC011-191415-
/O.NEW.KFSD.FF.W.0028.180719T1046Z-180719T1415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Sioux Falls SD
546 AM CDT THU JUL 19 2018

The National Weather Service in Sioux Falls has issued a

* Flash Flood Warning for...
  Southwestern Lincoln County in southwestern Minnesota...
  East central Brookings County in east central South Dakota...

* Until 915 AM CDT.

* At 546 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to 5 inches of rain have 
  fallen. Flash flooding is expected to begin shortly.

* Flash flooding will remain over mainly rural areas of southwestern
  Lincoln and east central Brookings Counties.

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.

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, country roads, farmland, and other low lying
spots.

&&

LAT...LON 4449 9628 4425 9633 4425 9654 4449 9653

$$

Ferguson

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 18, 7:48 PM CDT	Severe Thunderstorm Warning	FSD	Brule, Charles Mix, Gregory	42 min
Jul 18, 8:28 PM CDT	Severe Thunderstorm Warning	FSD	Aurora, Brule, Charles Mix, Gregory	32 min
Jul 19, 3:02 AM CDT	Flash Flood Warning	FSD	Brookings	6 hr
Jul 19, 6:49 AM CDT	River Flood Warning	FSD	Brookings	41 hr
Jul 19, 8:54 AM CDT	Areal Flood Warning	FSD	Brookings	12 hr
Jul 19, 9:07 AM CDT	River Flood Warning	FSD	Brookings, Moody	6 days

Nearby

Flash Flood Warnings in South Dakota, 2018 Flash Flood Warnings in Minnesota, 2018 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.