Alert archive / Nebraska / Flash Flood Warnings in 2018

Flash Flood Warning 1, NWS North Platte, NE

April 30, 2018Custer County, Nebraska

NWS North Platte, NE issued this flash flood warning at Apr 30, 2018, 10:19 PM CDT for Custer 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: Apr 30, 2018, 10:19 PM CDT (03:19 UTC)
Expired: May 1, 2018, 1:15 AM CDT
In force: 3 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), 119 km from the middle of the area, began a volume at 03:19 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, 3.3 hours before the alert went out and 116 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: 67 J/kg
Mixed-layer CIN: -221 J/kg
Mixed-layer LCL: 2671 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 127 m²/s²
0-3 km storm-relative helicity: 206 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

073 
WGUS53 KLBF 010319
FFWLBF
NEC041-010615-
/O.NEW.KLBF.FF.W.0001.180501T0319Z-180501T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service North Platte NE
1019 PM CDT MON APR 30 2018

The National Weather Service in North Platte has issued a

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

* Until 115 AM CDT

* At 1019 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 expected to begin shortly.

* Some locations that will experience flooding include...
  Sargent, Comstock, Weissert, Westerville, Big Oak Canyon, Arcadia
  Diversion Dam State Wildlife Management Area, Divide Hill and
  Wescott.

Additional rainfall amounts of 1 to 2 inches is possible in the 
warned area.

This includes the following highways...
 Highway 183 between mile markers 97 and 121.
 Highway 2 near mile marker 281.

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.

&&

LAT...LON 4138 9920 4139 9961 4174 9941 4174 9921
      4140 9921 4139 9920

$$

CDC

1 follow-up statement

441 
WGUS73 KLBF 010412
FFSLBF

Flash Flood Statement
National Weather Service North Platte NE
1112 PM CDT MON APR 30 2018

NEC041-010615-
/O.CON.KLBF.FF.W.0001.000000T0000Z-180501T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Custer NE-
1112 PM CDT MON APR 30 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 115 AM CDT FOR
NORTHEASTERN CUSTER COUNTY...

At 1110 PM CDT, Doppler radar indicated thunderstorms producing 
heavy rain have moved east of the warned area. Up to four inches of 
rain have already fallen. Flash flooding should diminish.

Some locations that will experience flooding include...
Sargent, Comstock, Weissert, Westerville, Big Oak Canyon, Arcadia
Diversion Dam State Wildlife Management Area, Divide Hill and
Wescott.

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

This includes the following highways...
 Highway 183 between mile markers 97 and 121.
 Highway 2 near mile marker 281.

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.

&&

LAT...LON 4138 9920 4139 9961 4174 9941 4174 9921
      4140 9921 4139 9920

$$

CDC

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 30, 7:04 PM CDT	Severe Thunderstorm Warning	LBF	Holt	41 min
Apr 30, 7:22 PM CDT	Severe Thunderstorm Warning	LBF	Holt	38 min
Apr 30, 7:24 PM CDT	Severe Thunderstorm Warning	LBF	Custer	51 min
Apr 30, 7:37 PM CDT	Special Weather Statement	LBF	Lincoln	38 min
Apr 30, 7:37 PM CDT	Severe Thunderstorm Warning	LBF	Holt	38 min
Apr 30, 7:41 PM CDT	Severe Thunderstorm Warning	LBF	Garfield, Holt, Loup, Rock	49 min
Apr 30, 7:47 PM CDT	Severe Thunderstorm Warning	LBF	Boyd, Holt	43 min
Apr 30, 8:14 PM CDT	Severe Thunderstorm Warning	LBF	Custer	46 min
Apr 30, 8:18 PM CDT	Severe Thunderstorm Warning	LBF	Custer	42 min
Apr 30, 8:51 PM CDT	Severe Thunderstorm Warning	LBF	Custer	39 min
Apr 30, 9:11 PM CDT	Areal Flood Advisory	LBF	Custer	67 min
Apr 30, 9:40 PM CDT	Special Weather Statement	LBF	Garfield, Wheeler	65 min
Apr 30, 9:42 PM CDT	Special Weather Statement	LBF	Garfield, Wheeler	63 min
Apr 30, 9:43 PM CDT	Special Weather Statement	LBF	Garfield, Wheeler	62 min
Apr 30, 10:45 PM CDT	Special Weather Statement	LBF	Garfield, Wheeler	60 min
Apr 30, 10:49 PM CDT	Areal Flood Advisory	LBF	Garfield	116 min
Apr 30, 11:46 PM CDT	Special Weather Statement	LBF	Wheeler	59 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.