Alert archive / Nebraska / Flash Flood Warnings in 2020

Flash Flood Warning 7, NWS North Platte, NE

July 25, 2020Custer County, Logan County, Nebraska

NWS North Platte, NE issued this flash flood warning at Jul 25, 2020, 9:36 PM CDT for Custer County, Logan 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 25, 2020, 9:36 PM CDT (02:36 UTC)
Expired
Jul 26, 2020, 12:30 AM CDT
In force
3 hr
Issued by
NWS North Platte, NE
Area
Storm-based polygon
Flood severity
None

Counties Custer County, NE, Logan County, NE

The radar

The North Platte radar (KLNX), 69 km from the middle of the area, began a volume at 02:35 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, 2.6 hours before the alert went out and 84 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-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 00:00Z on 2020-07-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 763 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 00:00Z on 2020-07-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
763 J/kg
Mixed-layer CIN
-61 J/kg
Mixed-layer LCL
2341 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
89 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted.

212 
WGUS53 KLBF 260236
FFWLBF
NEC041-113-260530-
/O.NEW.KLBF.FF.W.0007.200726T0236Z-200726T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service North Platte NE
936 PM CDT Sat Jul 25 2020

The National Weather Service in North Platte has issued a

* Flash Flood Warning for...
  Eastern Logan County in west central Nebraska...
  Northwestern Custer County in central Nebraska...

* Until 1230 AM CDT.

* At 935 PM CDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to three inches of rain have 
  already fallen. 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...
  Anselmo, Gandy, Victoria Springs State Recreation Area, Lillian,
  Logan, Milburn, Shanklin Bluff, Tarboz Lake, Walworth, Hoagland and
  Gates.

Additional rainfall amounts up to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4173 9943 4161 9954 4140 10055 4174 10032

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

$$

Roberg
2 follow-up statements
788 
WGUS73 KLBF 260345
FFSLBF

Flash Flood Statement
National Weather Service North Platte NE
1045 PM CDT Sat Jul 25 2020

NEC041-113-260530-
/O.CON.KLBF.FF.W.0007.000000T0000Z-200726T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Logan NE-Custer NE-
1045 PM CDT Sat Jul 25 2020

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1230 AM CDT FOR
EASTERN LOGAN AND NORTHWESTERN CUSTER COUNTIES...

At 1043 PM CDT, Doppler radar indicated thunderstorms producing 
moderte to heavy rain continued across the warned area. Three to 
five inches of rain have already fallen across northwest Custer 
County. 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...
Anselmo, Gandy, Victoria Springs State Recreation Area, Lillian,
Logan, Milburn, Shanklin Bluff, Tarboz Lake, Walworth, Hoagland and
Gates.

Additional rainfall amounts of one inch are possible in the warned 
area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 4173 9943 4161 9954 4140 10055 4174 10032

FLASH FLOOD...RADAR INDICATED

$$

Roberg
280 
WGUS73 KLBF 260525
FFSLBF

Flash Flood Statement
National Weather Service North Platte NE
1225 AM CDT Sun Jul 26 2020

NEC041-113-260534-
/O.EXP.KLBF.FF.W.0007.000000T0000Z-200726T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Logan NE-Custer NE-
1225 AM CDT Sun Jul 26 2020

...THE FLASH FLOOD WARNING FOR EASTERN LOGAN AND NORTHWESTERN CUSTER
COUNTIES WILL EXPIRE AT 1230 AM CDT...

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

LAT...LON 4173 9943 4161 9954 4140 10055 4174 10032

$$

Buttler

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 25, 7:06 PM CDTFlash Flood WarningLBFBlaine, Brown, Cherry, Thomas2 hr
Jul 25, 7:14 PM CDTSevere Thunderstorm WarningLBFBlaine, Brown46 min
Jul 25, 7:19 PM CDTAreal Flood AdvisoryLBFHayes, Lincoln3 hr
Jul 25, 7:26 PM CDTSevere Thunderstorm WarningLBFArthur, McPherson49 min
Jul 25, 7:30 PM CDTSpecial Weather StatementLBFGarden45 min
Jul 25, 7:40 PM CDTSpecial Weather StatementLBFChase50 min
Jul 25, 8:03 PM CDTSpecial Weather StatementLBFLoup42 min
Jul 25, 8:19 PM CDTSpecial Weather StatementLBFLincoln41 min
Jul 25, 8:22 PM CDTSevere Thunderstorm WarningLBFLincoln34 min
Jul 25, 8:34 PM CDTSevere Thunderstorm WarningLBFChase, Keith, Perkins44 min
Jul 25, 8:51 PM CDTSevere Thunderstorm WarningLBFKeith, Perkins39 min
Jul 25, 9:06 PM CDTSpecial Weather StatementLBFLogan39 min
Jul 25, 9:12 PM CDTSpecial Weather StatementLBFLoup48 min
Jul 25, 9:29 PM CDTFlash Flood WarningLBFKeith3 hr
Jul 25, 10:24 PM CDTAreal Flood AdvisoryLBFCuster3 hr

Nearby

Flash Flood Warnings in Nebraska, 2020Every 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.