Alert archive / Nebraska / Flash Flood Warnings in 2011

Flash Flood Warning 25, NWS Cheyenne, WY

August 29, 2011Banner County, Cheyenne County, Kimball County, Nebraska

NWS Cheyenne, WY issued this flash flood warning at Aug 29, 2011, 4:12 PM MDT for Banner County, Cheyenne County, Kimball County, Nebraska. It was in force for 3 hr. 2 reports 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 29, 2011, 4:12 PM MDT (22:12 UTC)
Expired
Aug 29, 2011, 7:00 PM MDT
In force
3 hr
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Flood severity
None

Counties Banner County, NE, Cheyenne County, NE, Kimball County, NE

The radar

The Cheyenne radar (KCYS), 135 km from the middle of the area, began a volume at 22:13 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 29, 5:00 PM MDTHEAVY RAIN 2.52 Se Dalton, NESTILL RAINING HARD
Aug 29, 5:50 PM MDTFLASH FLOOD7 Se Sidney, NECHEYENNE COUNTY DISPATCH REPORTS MOST COUNTY ROADS SOUTHEAST OF SIDNEY TO THE DEUEL COUNTY LINE REMAIN FLOODED. TRAVEL IN SOUTHEASTERN CHEYENNE COUNTY CONTINUES TO BE DISCOURAGED EARLY THIS EVENING.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 10.2 hours before the alert went out and 141 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, Denver, CO at 12:00Z on 2011-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 157 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, Denver, CO at 12:00Z on 2011-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 square meters per square second.193958Sfc1 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
157 J/kg
Mixed-layer CIN
-137 J/kg
Mixed-layer LCL
1100 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
76 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

672 
WGUS55 KCYS 292212
FFWCYS
NEC007-033-105-300100-
/O.NEW.KCYS.FF.W.0025.110829T2212Z-110830T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
412 PM MDT MON AUG 29 2011

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CHEYENNE COUNTY IN THE PANHANDLE OF NEBRASKA...
  EXTREME SOUTHEASTERN BANNER COUNTY IN THE PANHANDLE OF NEBRASKA...
  KIMBALL COUNTY IN THE PANHANDLE OF NEBRASKA...

* UNTIL 700 PM MDT

* AT 408 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE      
  WARNED AREA. RADAR ESTIMATED RAINFALL UP TO 3 INCHES HAS FALLEN    
  OVER SOUTHEASTERN CHEYENNE COUNTY. A LINE OF THUNDERSTORMS WITH    
  THUNDERSTORMS CAPABLE OF PRODUCING TORRENTIAL RAINFALL IS MOVING   
  INTO KIMBALL COUNTY AND WILL FURTHER IMPACT MOST OF CHEYENNE       
  COUNTY THROUGH 7 PM.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  KIMBALL...SIDNEY...BENNETT RESERVOIR...BROWNSON...COLTON...
  DALTON...DIX...GURLEY...LODGEPOLE...LORENZO...OLIVER RESERVOIR...
  PANORAMA POINT...POTTER...SIDNEY AIRPORT AND SUNOL.

AT 358 PM...CHEYENNE COUNTY DISPATCH REPORTS MOST COUNTY ROADS 
SOUTHEAST OF SIDNEY FLOODED AND CLOSED. TRAVEL IS NOT RECOMMENDED 
ACROSS SOUTHEAST CHEYENNE COUNTY THIS AFTERNOON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY 
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN 
CHEYENNE.

&&

LAT...LON 4099 10263 4100 10406 4106 10405 4141 10374
      4143 10262 4110 10259

$$

CLAYCOMB
2 follow-up statements
013 
WGUS75 KCYS 292355
FFSCYS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
555 PM MDT MON AUG 29 2011

NEC007-105-300006-
/O.CAN.KCYS.FF.W.0025.000000T0000Z-110830T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BANNER NE-KIMBALL NE-
555 PM MDT MON AUG 29 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR KIMBALL AND EXTREME
SOUTHEASTERN BANNER COUNTIES IS CANCELLED...

EXCESS RUNOFF FROM HEAVY 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 4099 10263 4100 10292 4122 10260 4110 10259

$$

NEC033-300100-
/O.CON.KCYS.FF.W.0025.000000T0000Z-110830T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CHEYENNE NE-
555 PM MDT MON AUG 29 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHEASTERN CHEYENNE
COUNTY UNTIL 700 PM MDT...

AT 551 PM MDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED 
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. RADAR 
ESTIMATED STORM TOTAL RAINFALL OF THREE TO THREE AND A HALF INCHES 
HAS FALLEN OVER PORTIONS OF SOUTHEASTERN CHEYENNE COUNTY THIS 
AFTERNOON.

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
LODGEPOLE.

CHEYENNE COUNTY LAW ENFORCEMENT CONTINUES TO REPORT MOST COUNTY 
ROADS FLOODED SOUTHEAST OF SIDNEY. TRAVEL ACROSS SOUTHEASTERN 
CHEYENNE COUNTY SOUTHEAST OF SIDNEY CONTINUES TO BE DISCOURAGED. 

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...LODGEPOLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REPORT FLOODING TO THE NEAREST LAW ENFORCEMENT AGENCY SO THAT THEY
MAY TAKE APPROPRIATE ACTION TO CLOSE FLOODED ROADWAYS. THEY WILL
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE IN CHEYENNE.

&&

LAT...LON 4099 10263 4100 10292 4122 10260 4110 10259

$$

CLAYCOMB
702 
WGUS75 KCYS 300050
FFSCYS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
650 PM MDT MON AUG 29 2011

NEC033-300106-
/O.EXP.KCYS.FF.W.0025.000000T0000Z-110830T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CHEYENNE NE-
650 PM MDT MON AUG 29 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTHEASTERN
CHEYENNE COUNTY WILL BE ALLOWED TO EXPIRE AT 700 PM MDT...

EXCESS RUNOFF FROM HEAVY 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 4099 10263 4100 10292 4122 10260 4110 10259

$$

CLAYCOMB

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 28, 6:49 PM MDTSpecial Weather StatementCYSKimball56 min
Aug 28, 8:20 PM MDTSpecial Weather StatementCYSBanner55 min
Aug 29, 1:34 PM MDTFlash Flood WarningCYSCheyenne3 hr
Aug 29, 1:43 PM MDTSevere Thunderstorm WarningCYSCheyenne49 min
Aug 29, 2:42 PM MDTSevere Thunderstorm WarningCYSSioux63 min
Aug 29, 3:20 PM MDTSpecial Weather StatementCYSCheyenne55 min
Aug 29, 3:25 PM MDTSevere Thunderstorm WarningCYSBanner, Kimball, Scotts Bluff65 min
Aug 29, 3:41 PM MDTSevere Thunderstorm WarningCYSDawes, Sioux64 min
Aug 29, 4:21 PM MDTSevere Thunderstorm WarningCYSBanner, Cheyenne, Kimball, Morrill, Scotts Bluff54 min
Aug 29, 4:49 PM MDTSpecial Weather StatementCYSDawes56 min
Aug 29, 4:53 PM MDTSevere Thunderstorm WarningCYSBox Butte, Dawes25 min
Aug 29, 5:13 PM MDTSevere Thunderstorm WarningCYSCheyenne29 min
Aug 29, 5:17 PM MDTTornado WarningCYSDawes15 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.