Alert archive / Nebraska / Flash Flood Warnings in 2020

Flash Flood Warning 3, NWS North Platte, NE

July 10, 2020Custer County, Nebraska

NWS North Platte, NE issued this flash flood warning at Jul 10, 2020, 5:00 PM CDT for Custer County, Nebraska. It was in force for 111 min. 2 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: Jul 10, 2020, 5:00 PM CDT (22:00 UTC)
Expired: Jul 10, 2020, 6:51 PM CDT
In force: 111 min
Issued by: NWS North Platte, NE
Area: Storm-based polygon
Flood severity: None

County Custer County, NE

The radar

The North Platte radar (KLNX), 126 km from the middle of the area, began a volume at 21:58 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
Jul 10, 5:30 PM CDT	FLASH FLOOD	Broken Bow, NE	FAIRGROUNDS UNDER WATER IN BROKEN BOW. WATER STANDING AND FLOWING ALL OVER TOWN.
Jul 10, 5:30 PM CDT	FLASH FLOOD	Mason City, NE	FLOOD WATERS WASHED THE FOOTERS OF A BUILDING AND IT IS ABOUT TO FALL DOWN.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 10.0 hours before the alert went out and 98 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: 757 J/kg
Mixed-layer CIN: -320 J/kg
Mixed-layer LCL: 1542 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 48 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

490 
WGUS53 KLBF 102200
FFWLBF
NEC041-110100-
/O.NEW.KLBF.FF.W.0003.200710T2200Z-200711T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service North Platte NE
500 PM CDT Fri Jul 10 2020

The National Weather Service in North Platte has issued a

* Flash Flood Warning for...
  Southeastern Custer County in central Nebraska...

* Until 800 PM CDT.

* At 459 PM CDT, Doppler radar and automated gauges indicated
  thunderstorms producing heavy rain across the warned area. Up to 
  one inch of rain has fallen in fifteen minutes. Flash flooding is 
  ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flooding of small creeks and streams, urban areas, 
           highways, streets and underpasses as well as other 
           drainage and low lying areas.

* Some locations that will experience flooding include...
  Broken Bow, Ansley, Mason City, Berwyn, Westerville, Buckeye, Block
  Hill Basin, Arcadia Diversion Dam State Wildlife Management Area,
  Gavin Siding, Intersection of Highway 183 and Cumro Road and Cumro.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4105 9951 4141 9971 4150 9921 4105 9921

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...2-3 INCHES IN 1 HOUR

$$

CDC

1 follow-up statement

077 
WGUS73 KLBF 102351
FFSLBF

Flash Flood Statement
National Weather Service North Platte NE
651 PM CDT Fri Jul 10 2020

NEC041-110000-
/O.CAN.KLBF.FF.W.0003.000000T0000Z-200711T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Custer NE-
651 PM CDT Fri Jul 10 2020

...THE FLASH FLOOD WARNING FOR SOUTHEASTERN CUSTER COUNTY IS
CANCELLED...

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

LAT...LON 4105 9951 4141 9971 4150 9921 4105 9921

$$

CDC

The office that day

Everything else NWS North Platte, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 9, 8:08 PM CDT	Special Weather Statement	LBF	Grant, Sheridan	52 min
Jul 9, 8:59 PM CDT	Special Weather Statement	LBF	Hooker	46 min
Jul 9, 9:28 PM CDT	Severe Thunderstorm Warning	LBF	Cherry, Garden, Grant, Sheridan	47 min
Jul 9, 9:33 PM CDT	Special Weather Statement	LBF	McPherson	42 min
Jul 9, 10:19 PM CDT	Severe Thunderstorm Warning	LBF	Arthur, Garden, Grant, Hooker, McPherson	41 min
Jul 9, 10:46 PM CDT	Areal Flood Advisory	LBF	Arthur, Grant, Hooker, McPherson	66 min
Jul 9, 10:49 PM CDT	Special Weather Statement	LBF	Chase	41 min
Jul 9, 11:00 PM CDT	Special Weather Statement	LBF	Arthur	45 min
Jul 9, 11:22 PM CDT	Severe Thunderstorm Warning	LBF	McPherson	38 min
Jul 9, 11:26 PM CDT	Special Weather Statement	LBF	Keith	49 min
Jul 9, 11:37 PM CDT	Severe Thunderstorm Warning	LBF	McPherson	23 min
Jul 9, 11:46 PM CDT	Severe Thunderstorm Warning	LBF	Lincoln	59 min
Jul 10, 12:30 AM CDT	Severe Thunderstorm Warning	LBF	Lincoln	50 min
Jul 10, 12:33 AM CDT	Special Weather Statement	LBF	Custer	42 min
Jul 10, 11:39 AM CDT	Severe Thunderstorm Warning	LBF	Brown, Cherry, Keya Paha	51 min
Jul 10, 11:50 AM CDT	Severe Thunderstorm Warning	LBF	Brown, Cherry	40 min
Jul 10, 12:22 PM CDT	Severe Thunderstorm Warning	LBF	Brown, Keya Paha, Rock	38 min
Jul 10, 12:52 PM CDT	Special Weather Statement	LBF	Brown	38 min
Jul 10, 1:03 PM CDT	Special Weather Statement	LBF	Rock	42 min
Jul 10, 1:32 PM CDT	Special Weather Statement	LBF	Cherry	43 min
Jul 10, 1:48 PM CDT	Severe Thunderstorm Warning	LBF	Cherry	42 min
Jul 10, 2:26 PM CDT	Severe Thunderstorm Warning	LBF	Cherry, Thomas	49 min
Jul 10, 2:59 PM CDT	Severe Thunderstorm Warning	LBF	Blaine, Brown, Cherry, Thomas	46 min
Jul 10, 3:33 PM CDT	Severe Thunderstorm Warning	LBF	Blaine, Custer, Loup	42 min
Jul 10, 3:59 PM CDT	Severe Thunderstorm Warning	LBF	Blaine, Custer, Loup	46 min
Jul 10, 4:26 PM CDT	Severe Thunderstorm Warning	LBF	Custer	49 min
Jul 10, 4:39 PM CDT	Severe Thunderstorm Warning	LBF	Custer	51 min
Jul 10, 5:13 PM CDT	Severe Thunderstorm Warning	LBF	Custer	37 min
Jul 10, 5:29 PM CDT	Severe Thunderstorm Warning	LBF	Custer	31 min

Nearby

Flash Flood Warnings in Nebraska, 2020 Every flash flood warning in 2020

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.