Alert archive / Nebraska / Flash Flood Warnings in 2017

Flash Flood Warning 8, NWS North Platte, NE

August 15, 2017Custer County, Nebraska

NWS North Platte, NE issued this flash flood warning at Aug 15, 2017, 12:36 PM CDT for Custer County, Nebraska. It was in force for 6 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
Aug 15, 2017, 12:36 PM CDT (17:36 UTC)
Expired
Aug 15, 2017, 6:30 PM CDT
In force
6 hr
Issued by
NWS North Platte, NE
Area
Storm-based polygon
Flood severity
None

County Custer County, NE

The radar

The North Platte radar (KLNX), 85 km from the middle of the area, began a volume at 17:37 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

TimeReportWhereRemark
Aug 15, 12:41 PM CDTHEAVY RAIN 0.5Merna, NESPOTTER REPORTED A HALF INCH OF RAIN IN 20 MINUTES WITH WATER COVERING THE ROAD TO 2 INCH DEPTH IN TOWN.

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, 5.6 hours before the alert went out and 76 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 12:00Z on 2017-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 418 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 12:00Z on 2017-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 62 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
418 J/kg
Mixed-layer CIN
-256 J/kg
Mixed-layer LCL
763 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
62 m²/s²
0-3 km storm-relative helicity
71 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

As transmitted.

849 
WGUS53 KLBF 151736
FFWLBF
NEC041-152330-
/O.NEW.KLBF.FF.W.0008.170815T1736Z-170815T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service North Platte NE
1236 PM CDT TUE AUG 15 2017

The National Weather Service in North Platte has issued a

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

* Until 630 PM CDT

* At 1234 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area from southwest into west central 
  Custer County. Rainfall amounts from 2 to 4 inches inches of rain 
  have fallen with thunderstorm training to increase the threat for 
  flash flooding. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Broken Bow, Arnold, Callaway, Sargent, Merna, Anselmo, Victoria
  Springs State Recreation Area, Lillian, Round Valley, Walworth,
  Milldale, Pleasant Hill, Big Oak Canyon, Finchville, Divide Hill
  and Gates.

This includes the following highways...
 Highway 183 between mile markers 108 and 121.
 Highway 2 between mile markers 257 and 278.
 Highway 92 between mile markers 247 and 273.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4110 10024 4148 10025 4174 9964 4173 9921
      4162 9921

$$

Keck
2 follow-up statements
475 
WGUS73 KLBF 151922
FFSLBF

Flash Flood Statement
National Weather Service North Platte NE
222 PM CDT TUE AUG 15 2017

NEC041-152330-
/O.CON.KLBF.FF.W.0008.000000T0000Z-170815T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Custer NE-
222 PM CDT TUE AUG 15 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM CDT FOR
CENTRAL CUSTER COUNTY...

At 218 PM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area have diminished. One to two inches of 
rain have fallen this morning and early afternoon. However, with 
this morning's rain and that which has fallen in the last few days, 
any additional rainfall will cause flash flooding easily. Additional 
thunderstorm development is expected later this afternoon and 
evening.

Some locations that will experience flooding include...
Broken Bow, Arnold, Callaway, Sargent, Merna, Anselmo, Victoria
Springs State Recreation Area, Lillian, Round Valley, Walworth,
Milldale, Pleasant Hill, Big Oak Canyon, Finchville, Divide Hill and
Gates.

Additional rainfall amounts of one to two inches are possible in the 
warned area later today.

This includes the following highways...
 Highway 183 between mile markers 108 and 121.
 Highway 2 between mile markers 257 and 278.
 Highway 92 between mile markers 247 and 273.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4110 10024 4148 10025 4174 9964 4173 9921
      4162 9921

$$

JWS
190 
WGUS73 KLBF 152101
FFSLBF

Flash Flood Statement
National Weather Service North Platte NE
401 PM CDT TUE AUG 15 2017

NEC041-152108-
/O.CAN.KLBF.FF.W.0008.000000T0000Z-170815T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Custer NE-
401 PM CDT TUE AUG 15 2017

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

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

A flash flood watch remains in effect for the area. Additional 
thunderstorms with heavy rain are expected this evening and 
overnight. Therefore additional flooding will be possible.

LAT...LON 4110 10024 4148 10025 4174 9964 4173 9921
      4162 9921

$$

JWS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 9:17 PM CDTSpecial Weather StatementLBFSheridan28 min
Aug 14, 9:26 PM CDTSpecial Weather StatementLBFSheridan49 min
Aug 14, 9:31 PM CDTSevere Thunderstorm WarningLBFCherry, Sheridan44 min
Aug 14, 10:09 PM CDTSpecial Weather StatementLBFGrant66 min
Aug 14, 10:37 PM CDTSpecial Weather StatementLBFCherry, Grant38 min
Aug 14, 11:12 PM CDTSpecial Weather StatementLBFCherry, Hooker48 min
Aug 14, 11:58 PM CDTSpecial Weather StatementLBFCherry, Hooker47 min
Aug 15, 12:27 AM CDTSpecial Weather StatementLBFSheridan48 min
Aug 15, 3:53 AM CDTAreal Flood AdvisoryLBFHolt3 hr
Aug 15, 8:30 AM CDTSpecial Weather StatementLBFGarfield, Wheeler60 min
Aug 15, 11:12 AM CDTSpecial Weather StatementLBFGarfield63 min
Aug 15, 11:49 AM CDTSevere Thunderstorm WarningLBFGarfield, Holt41 min
Aug 15, 11:57 AM CDTSpecial Weather StatementLBFCuster48 min
Aug 15, 11:59 AM CDTSpecial Weather StatementLBFLincoln46 min
Aug 15, 12:06 PM CDTSevere Thunderstorm WarningLBFLincoln39 min
Aug 15, 12:28 PM CDTSevere Thunderstorm WarningLBFCuster, Loup47 min
Aug 15, 12:30 PM CDTSevere Thunderstorm WarningLBFHolt45 min
Aug 15, 12:39 PM CDTFlash Flood WarningLBFGarfield, Holt6 hr
Aug 15, 12:49 PM CDTSpecial Weather StatementLBFLogan41 min
Aug 15, 12:58 PM CDTSevere Thunderstorm WarningLBFCuster, Logan30 min
Aug 15, 2:08 PM CDTSpecial Weather StatementLBFGarfield52 min
Aug 15, 3:40 PM CDTSpecial Weather StatementLBFSherman50 min
Aug 15, 4:15 PM CDTSpecial Weather StatementLBFLoup, Rock60 min
Aug 15, 5:08 PM CDTSpecial Weather StatementLBFGarfield, Holt97 min
Aug 15, 5:31 PM CDTSevere Thunderstorm WarningLBFCuster, Garfield, Loup44 min
Aug 15, 5:43 PM CDTSpecial Weather StatementLBFCuster47 min
Aug 15, 5:55 PM CDTFlash Flood WarningLBFCuster, Garfield, Loup6 hr
Aug 15, 6:13 PM CDTSevere Thunderstorm WarningLBFCuster47 min
Aug 15, 6:17 PM CDTSpecial Weather StatementLBFHolt43 min
Aug 15, 6:32 PM CDTFlash Flood WarningLBFLogan3 hr
Aug 15, 6:45 PM CDTSpecial Weather StatementLBFLogan45 min
Aug 15, 6:47 PM CDTSpecial Weather StatementLBFWheeler58 min
Aug 15, 6:51 PM CDTSpecial Weather StatementLBFArthur, Keith54 min

Nearby

Flash Flood Warnings in Nebraska, 2017Every flash flood warning in 2017

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.