Alert archive / Nebraska / Flash Flood Warnings in 2020

Flash Flood Warning 9, NWS North Platte, NE

July 29, 2020Frontier County, Nebraska

NWS North Platte, NE issued this flash flood warning at Jul 29, 2020, 10:29 PM CDT for Frontier County, Nebraska. 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 29, 2020, 10:29 PM CDT (03:29 UTC)
Expired: Jul 30, 2020, 1:30 AM CDT
In force: 3 hr
Issued by: NWS North Platte, NE
Area: Storm-based polygon
Flood severity: None

County Frontier County, NE

The radar

The Grand Island radar (KUEX), 158 km from the middle of the area, began a volume at 03:32 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

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 3.5 hours before the alert went out and 77 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: 569 J/kg
Mixed-layer CIN: -106 J/kg
Mixed-layer LCL: 1837 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 28 m²/s²
0-3 km storm-relative helicity: 142 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

As transmitted.

617 
WGUS53 KLBF 300329
FFWLBF
NEC063-300630-
/O.NEW.KLBF.FF.W.0009.200730T0329Z-200730T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service North Platte NE
1029 PM CDT Wed Jul 29 2020

The National Weather Service in North Platte has issued a

* Flash Flood Warning for...
  Frontier County in southwestern Nebraska...

* Until 130 AM CDT.

* At 1028 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding is ongoing or
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  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...
  Curtis, Eustis, Moorefield, Stockville, Medicine Creek Reservoir
  State Recreation Area, Maywood, Orafino, Freedom and Dancing Leaf
  Earth Lodge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 4035 10057 4070 10078 4070 9998 4044 9998
      4044 10009 4036 10010

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

$$

CDC

2 follow-up statements

974 
WGUS73 KLBF 300501
FFSLBF

Flash Flood Statement
National Weather Service North Platte NE
1201 AM CDT Thu Jul 30 2020

NEC063-300630-
/O.CON.KLBF.FF.W.0009.000000T0000Z-200730T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Frontier NE-
1201 AM CDT Thu Jul 30 2020

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 130 AM CDT FOR
FRONTIER COUNTY...

At 1201 AM CDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area.  Flash flooding is expected to begin
shortly.

Some locations that will experience flooding include...
Curtis, Eustis, Moorefield, Stockville, Medicine Creek Reservoir
State Recreation Area, Maywood, Orafino, Freedom and Dancing Leaf
Earth Lodge.

This includes Highway 83 between mile markers 36 and 51.
 
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.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 4035 10057 4070 10078 4070 9998 4044 9998
      4044 10009 4036 10010

$$

Snively

526 
WGUS73 KLBF 300629
FFSLBF

Flash Flood Statement
National Weather Service North Platte NE
129 AM CDT Thu Jul 30 2020

NEC063-300638-
/O.EXP.KLBF.FF.W.0009.000000T0000Z-200730T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Frontier NE-
129 AM CDT Thu Jul 30 2020

...THE FLASH FLOOD WARNING FOR FRONTIER COUNTY WILL EXPIRE AT 130 AM
CDT...

The heavy rain has ended for tonight. Flooding is no longer expected 
to pose an immediate threat. Please continue to heed any remaining 
road closures. Additional rain showers and thunderstorms are likely 
again Thursday.

LAT...LON 4035 10057 4070 10078 4070 9998 4044 9998
      4044 10009 4036 10010

$$

Snively

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 29, 7:01 PM CDT	Areal Flood Advisory	LBF	Cherry	3 hr
Jul 29, 7:18 PM CDT	Special Weather Statement	LBF	McPherson	42 min
Jul 29, 7:58 PM CDT	Areal Flood Warning	LBF	Hooker, McPherson, Thomas	3 hr
Jul 29, 8:00 PM CDT	Special Weather Statement	LBF	McPherson	45 min
Jul 29, 8:11 PM CDT	Flash Flood Warning	LBF	Boyd, Holt	3 hr
Jul 29, 8:37 PM CDT	Areal Flood Warning	LBF	Lincoln, Logan	3 hr
Jul 29, 8:44 PM CDT	Special Weather Statement	LBF	Lincoln	61 min
Jul 29, 8:54 PM CDT	Areal Flood Advisory	LBF	Lincoln	112 min
Jul 29, 9:24 PM CDT	Special Weather Statement	LBF	Lincoln	51 min
Jul 29, 9:28 PM CDT	Areal Flood Advisory	LBF	Custer	117 min
Jul 29, 9:37 PM CDT	Severe Thunderstorm Warning	LBF	Custer, Lincoln	38 min
Jul 29, 9:48 PM CDT	Special Weather Statement	LBF	Lincoln	42 min
Jul 29, 10:02 PM CDT	Areal Flood Advisory	LBF	Lincoln	84 min
Jul 29, 10:23 PM CDT	Severe Thunderstorm Warning	LBF	Frontier, Hayes, Lincoln	67 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.