Alert archive / Nebraska / Flash Flood Warnings in 2011

Flash Flood Warning 1, NWS North Platte, NE

May 19, 2011Keith County, Nebraska

NWS North Platte, NE issued this flash flood warning at May 19, 2011, 9:22 PM MDT for Keith County, Nebraska. It was in force for 71 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 19, 2011, 9:22 PM MDT (03:22 UTC)
Expired
May 19, 2011, 10:33 PM MDT
In force
71 min
Issued by
NWS North Platte, NE
Area
Storm-based polygon
Flood severity
None

County Keith County, NE

The radar

The North Platte radar (KLNX), 118 km from the middle of the area, began a volume at 03:24 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, 3.4 hours before the alert went out and 83 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 2011-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 113 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 2011-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 100 square meters per square second.1939587897Sfc1 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
113 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
535 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
100 m²/s²
0-3 km storm-relative helicity
186 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

966 
WGUS53 KLBF 200322
FFWLBF
NEC101-200630-
/O.NEW.KLBF.FF.W.0001.110520T0322Z-110520T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
922 PM MDT THU MAY 19 2011

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* FLASH FLOOD WARNING FOR MINOR FLOODING OF POOR DRAINAGE AREAS IN...
  EASTERN KEITH COUNTY IN SOUTHWEST NEBRASKA...

* UNTIL 1230 AM MDT

* AT 921 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE   
  WARNED AREA. 1 TO 2 INCHES OF RAIN WILL FALL IN ABOUT 1 HOURS TIME 
  PRODUCING FLOODING.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  OGALLALA...KEYSTONE...PAXTON...ROSCOE AND SARBEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE 
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. DO 
NOT ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND TO 
ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN 
WATER BEGINS RISING.

&&

LAT...LON 4134 10179 4135 10128 4102 10126 4101 10178

$$

CDC
2 follow-up statements
348 
WGUS73 KLBF 200351
FFSLBF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
951 PM MDT THU MAY 19 2011

NEC101-200630-
/O.CON.KLBF.FF.W.0001.000000T0000Z-110520T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KEITH NE-
951 PM MDT THU MAY 19 2011

...FLASH FLOOD WARNING FOR MINOR FLOODING OF POOR DRAINAGE AREAS
REMAINS IN EFFECT FOR EASTERN KEITH COUNTY UNTIL 1230 AM MDT...

AT 948 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THUNDERSTORMS WITH VERY HEAVY RAINFALL BETWEEN SARBEN AND PAXTON. 
AROUND 3/4 OF AN INCH OF RAIN HAS FALLEN IN SOME AREAS SOUTH OF  
INTERSTATE 80. UP TO 1 AND 1/2 INCHES OF TOTAL RAINFALL IS 
EXPECTED BEFORE THE THUNDERSTORMS MOVE NORTH OF THE WARNED AREA.

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING INCLUDE...
OGALLALA...KEYSTONE...PAXTON...ROSCOE AND SARBEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLOODING IS OBSERVED...ACT QUICKLY. DO NOT
ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND. DO NOT
STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

&&

LAT...LON 4134 10179 4135 10128 4102 10126 4101 10178

$$

CDC
585 
WGUS73 KLBF 200433
FFSLBF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1033 PM MDT THU MAY 19 2011

NEC101-200447-
/O.CAN.KLBF.FF.W.0001.000000T0000Z-110520T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KEITH NE-
1033 PM MDT THU MAY 19 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR EASTERN KEITH
COUNTY IS CANCELLED...

BETWEEN 1/2 AND 1 INCH OF RAIN FELL IN THE WARNED AREA. EXCESS 
RUNOFF FROM THIS RAIN HAS ENDED OVER THE WARNED AREA. STREAMS AND 
CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING TO 
RECEDE...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN 
OBSERVED...PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4134 10179 4135 10128 4102 10126 4101 10178

$$

CDC

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 6:27 PM MDTSevere Thunderstorm WarningLBFCuster34 min
May 20, 9:36 AM MDTRiver Flood WarningLBFLincoln35 hr

Nearby

Flash Flood Warnings in Nebraska, 2011Every flash flood warning in 2011

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.