Alert archive / Nebraska / Flash Flood Warnings in 2018

Flash Flood Warning 13, NWS Sioux Falls, SD

June 25, 2018Dakota County, Dixon County, Nebraska

NWS Sioux Falls, SD issued this flash flood warning at Jun 25, 2018, 5:49 PM CDT for Dakota County, Dixon County, Nebraska. 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: Jun 25, 2018, 5:49 PM CDT (22:49 UTC)
Expired: Jun 25, 2018, 9:45 PM CDT
In force: 4 hr
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Flood severity: None

Counties Dakota County, NE, Dixon County, NE

The radar

The Sioux Falls radar (KFSD), 129 km from the middle of the area, began a volume at 22:52 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

Time	Report	Where	Remark
Jun 25, 5:51 PM CDT	FLOOD	2 N Wakefield, NE	WATER OVER THE ROAD AT THE INTERSECTION OF HIGHWAY 35 AND HIGHWAY 9.

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, 10.8 hours before the alert went out and 130 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: 118 J/kg
Mixed-layer CIN: -61 J/kg
Mixed-layer LCL: 796 m above ground
0-6 km bulk shear: 9 kt
0-1 km storm-relative helicity: -89 m²/s²
0-3 km storm-relative helicity: -80 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

039 
WGUS53 KFSD 252249
FFWFSD
NEC043-051-260245-
/O.NEW.KFSD.FF.W.0013.180625T2249Z-180626T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Sioux Falls SD
549 PM CDT MON JUN 25 2018

The National Weather Service in Sioux Falls has issued a

* Flash Flood Warning for...
  Southwestern Dakota County in northeastern Nebraska...
  Southwestern Dixon County in northeastern Nebraska...

* Until 945 PM CDT.

* At 548 PM CDT, emergency management reported 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...
  Wakefield, Emerson, Allen, Concord, Martinsburg, Dixon In Dixon
  County and Waterbury.

Additional rainfall amounts of one to two inches are possible in the 
warned area this evening.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4258 9701 4247 9667 4228 9651 4226 9701

$$

BT

1 follow-up statement

565 
WGUS73 KFSD 260249
FFSFSD

Flash Flood Statement
National Weather Service Sioux Falls SD
949 PM CDT MON JUN 25 2018

NEC043-051-260258-
/O.EXP.KFSD.FF.W.0013.000000T0000Z-180626T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Dakota NE-Dixon NE-
949 PM CDT MON JUN 25 2018

...THE FLASH FLOOD WARNING FOR SOUTHWESTERN DAKOTA AND SOUTHWESTERN
DIXON COUNTIES HAS EXPIRED...

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

LAT...LON 4258 9701 4247 9667 4228 9651 4226 9701

$$

BT

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 24, 7:53 PM CDT	Flash Flood Warning	FSD	Dixon	3 hr
Jun 24, 9:05 PM CDT	Flash Flood Warning	FSD	Dakota, Dixon	3 hr
Jun 24, 9:52 PM CDT	Flash Flood Watch	FSD	Dakota, Dixon	25 hr
Jun 24, 10:41 PM CDT	Flash Flood Warning Emergency	FSD	Dakota	4 hr
Jun 24, 11:13 PM CDT	Flash Flood Warning	FSD	Dakota, Dixon	4 hr
Jun 25, 2:46 AM CDT	Areal Flood Warning	FSD	Dakota, Dixon	12 hr

Nearby

Flash Flood Warnings in Nebraska, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.