Alert archive / Nebraska / Flash Flood Warnings in 2011

Flash Flood Warning 19, NWS Cheyenne, WY

July 16, 2011Banner County, Morrill County, Scotts Bluff County, Nebraska

NWS Cheyenne, WY issued this flash flood warning at Jul 16, 2011, 11:30 PM MDT for Banner County, Morrill County, Scotts Bluff County, Nebraska. It was in force for 2 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 16, 2011, 11:30 PM MDT (05:30 UTC)
Expired
Jul 17, 2011, 1:45 AM MDT
In force
2 hr
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Flood severity
None

Counties Banner County, NE, Morrill County, NE, Scotts Bluff County, NE

The radar

The Cheyenne radar (KCYS), 147 km from the middle of the area, began a volume at 05:33 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

Denver, CO (KDNR), launched 00:00Z, 5.5 hours before the alert went out and 218 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 00:00Z on 2011-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1193 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 00:00Z on 2011-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 square meters per square second.19395878Sfc1 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
1193 J/kg
Mixed-layer CIN
-88 J/kg
Mixed-layer LCL
2264 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
288 m²/s²
Significant tornado parameter
0.0
Supercell composite
9.8

Open this sounding in Storm Lab

The text

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

237 
WGUS55 KCYS 170530
FFWCYS
NEC007-123-157-170830-
/O.NEW.KCYS.FF.W.0019.110717T0530Z-110717T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
1130 PM MDT SAT JUL 16 2011

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN SCOTTS BLUFF COUNTY IN THE PANHANDLE OF NEBRASKA...
  NORTHEASTERN BANNER COUNTY IN THE PANHANDLE OF NEBRASKA...
  WESTERN MORRILL COUNTY IN THE PANHANDLE OF NEBRASKA...

* UNTIL 230 AM MDT

* AT 1128 PM MDT...TRAINED WEATHER SPOTTERS REPORTED SLOW MOVING   
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. 2.50 
INCHES OF RAIN HAS FALLEN WITH THIS STORM IN SHORT PERIOD OF TIME.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  ANGORA...BAYARD...CHIMNEY ROCK...HUBBARD GAP...LAKE MINATARE...
  MINATARE AND REDINGTON.

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 4153 10317 4153 10367 4200 10349 4200 10328
      4201 10327 4201 10323 4200 10301

$$

MAZUR
1 follow-up statement
299 
WGUS75 KCYS 170745
FFSCYS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
145 AM MDT SUN JUL 17 2011

NEC007-123-157-170800-
/O.CAN.KCYS.FF.W.0019.000000T0000Z-110717T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BANNER NE-MORRILL NE-SCOTTS BLUFF NE-
145 AM MDT SUN JUL 17 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR EASTERN SCOTTS
BLUFF...WESTERN MORRILL AND NORTHEASTERN BANNER COUNTIES IS
CANCELLED...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. IF 
FLOODING HAS BEEN OBSERVED...PLEASE REPORT IT TO YOUR LOCAL LAW 
ENFORCEMENT AGENCY.

LAT...LON 4153 10317 4153 10367 4200 10349 4200 10328
      4201 10327 4201 10323 4200 10301

$$

MAZUR

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 9:53 PM MDTSevere Thunderstorm WarningCYSBanner, Kimball58 min
Jul 16, 9:58 PM MDTTornado WarningCYSKimball37 min
Jul 16, 10:15 PM MDTSevere Thunderstorm WarningCYSKimball35 min
Jul 16, 10:54 PM MDTSevere Thunderstorm WarningCYSBanner, Morrill, Scotts Bluff66 min
Jul 16, 11:27 PM MDTSevere Thunderstorm WarningCYSBox Butte, Morrill48 min
Jul 16, 11:48 PM MDTSevere Thunderstorm WarningCYSBox Butte, Dawes42 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.