Alert archive / Nebraska / Flash Flood Warnings in 2011

Flash Flood Warning 8, NWS Cheyenne, WY

June 19, 2011Cheyenne County, Nebraska

NWS Cheyenne, WY issued this flash flood warning at Jun 19, 2011, 4:21 PM MDT for Cheyenne County, Nebraska. It was in force for 6 hr. 7 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: Jun 19, 2011, 4:21 PM MDT (22:21 UTC)
Expired: Jun 19, 2011, 10:08 PM MDT
In force: 6 hr
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Flood severity: None

County Cheyenne County, NE

The radar

The Cheyenne radar (KCYS), 162 km from the middle of the area, began a volume at 22:21 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

Time	Report	Where	Remark
Jun 19, 5:49 PM MDT	FLASH FLOOD	3 S Sidney, NE	COUNTY ROAD 8 FLOODED
Jun 19, 5:49 PM MDT	FLASH FLOOD	4 Se Sidney, NE	INTERSECTION OF 113 AND 14 FLOODED AND CLOSED
Jun 19, 5:49 PM MDT	FLASH FLOOD	Sunol, NE	LODEGPOLE CREEK ALONG HIGHWAY 30 BETWEEN MILE MARKERS 83 AND 87 FLOODED
Jun 19, 6:02 PM MDT	HEAVY RAIN 2.76	Sidney, NE	6 HOUR PRECIP REPORTED AT 00Z
Jun 19, 6:35 PM MDT	HEAVY RAIN 2.76	Sidney, NE	THIS WAS A 6 HR TOTAL AS OF 00Z.SINCE THEN THEY HAVE RECIEVED ANOTHER 0.67
Jun 19, 7:17 PM MDT	FLASH FLOOD	5 S Sidney, NE	MOST COUNTY ROADS SOUTH OF SIDNEY ARE FLOODED AND CLOSED
Jun 19, 7:17 PM MDT	FLASH FLOOD	Lodgepole, NE	LODGEPOLE CREEK OUT OF ITS BANKS AT LODGEPOLE

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, 10.4 hours before the alert went out and 152 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: 330 J/kg
Mixed-layer CIN: -236 J/kg
Mixed-layer LCL: 1573 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 100 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

650 
WGUS55 KCYS 192221
FFWCYS
NEC033-200430-
/O.NEW.KCYS.FF.W.0008.110619T2221Z-110620T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
421 PM MDT SUN JUN 19 2011

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CHEYENNE COUNTY IN THE PANHANDLE OF NEBRASKA...

* UNTIL 1030 PM MDT

* AT 417 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE      
  WARNED AREA. RADAR ESTIMATED HOURLY RAINFALL AMOUNTS IN EXCESS OF  
  2 INCHES ARE BEING OBSERVED WITH THUNDERSTORMS OVER KIMBALL        
  COUNTY. THIS FLASH FLOOD WARNING WILL REPLACE THE WARNING          
  CURRENTLY IN EFFECT OVER WESTERN KIMBALL COUNTY.

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

** AT 407 PM FLASH FLOODING WAS REPORTED BY LAW ENFORCEMENT JUST 
SOUTH OF SUNOL AND EAST OF POTTER FROM THESE STORMS.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE 
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS 
SAFELY.

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

&&

LAT...LON 4101 10261 4100 10338 4143 10337 4143 10262
      4139 10261

$$

CLAYCOMB

1 follow-up statement

569 
WGUS75 KCYS 200408
FFSCYS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
1008 PM MDT SUN JUN 19 2011

NEC033-200422-
/O.CAN.KCYS.FF.W.0008.000000T0000Z-110620T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CHEYENNE NE-
1008 PM MDT SUN JUN 19 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR CHEYENNE COUNTY IS 
BEING REPLCED WITH AN AREAL FLOOD WARNING THROUGH 10 AM MONDAY...

EXCESS RUNOFF FROM HEAVY RAIN WILL CONTINUE OVER MUCH OF CHEYENNE 
COUNTY OVERNIGHT. IF FLOODING HAS BEEN OBSERVED...PLEASE REPORT IT 
TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4101 10261 4100 10338 4143 10337 4143 10262
      4139 10261

$$

CLAYCOMB

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 18, 6:23 PM MDT	Flash Flood Watch	CYS	Banner, Box Butte, Cheyenne, Dawes, Kimball, Morrill and 2 more	45 hr
Jun 19, 1:45 PM MDT	Severe Thunderstorm Warning	CYS	Kimball	60 min
Jun 19, 2:27 PM MDT	Flash Flood Warning	CYS	Kimball	70 min
Jun 19, 2:40 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne, Kimball	31 min
Jun 19, 2:53 PM MDT	Flash Flood Warning	CYS	Cheyenne	92 min
Jun 19, 3:08 PM MDT	Tornado Warning	CYS	Cheyenne	37 min
Jun 19, 3:25 PM MDT	Severe Thunderstorm Warning	CYS	Kimball	65 min
Jun 19, 3:33 PM MDT	Flash Flood Warning	CYS	Kimball	6 hr
Jun 19, 3:46 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne	44 min
Jun 19, 4:26 PM MDT	Severe Thunderstorm Warning	CYS	Banner, Cheyenne, Kimball, Morrill	23 min
Jun 19, 4:46 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne	59 min

Nearby

Flash Flood Warnings in Nebraska, 2011 Every 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.