Alert archive / Wyoming / Flash Flood Warnings in 2011

Flash Flood Warning 6, NWS Cheyenne, WY

June 19, 2011Laramie County, Wyoming

NWS Cheyenne, WY issued this flash flood warning at Jun 19, 2011, 3:11 PM MDT for Laramie County, Wyoming. It was in force for 5 hr. 4 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, 3:11 PM MDT (21:11 UTC)
Expired
Jun 19, 2011, 8:40 PM MDT
In force
5 hr
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Flood severity
None

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 12 km from the middle of the area, began a volume at 21:13 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
Jun 19, 3:28 PM MDTFLASH FLOODCheyenne, WYFLOODING WAS REPORTED AT THE AMES AVE UNDERPASS, ALSO AT THE 2200 BLOCK OF E 16TH ST, AND AT HINES AND 2ND AVE. THE MURDOCH PARKING LOT ALONG EAST LINCOLN WAY ALSO FLOODED.
Jun 19, 3:30 PM MDTFLASH FLOOD3 E Cheyenne, WYINTERSECTION FLOODED.
Jun 19, 3:38 PM MDTHEAVY RAIN 1.48Cheyenne, WYRAIN FELL IN 50 MIN. MARBLE SIZE HAIL ALSO. THIS WAS IN THE SOUTHEAST PART OF TOWN...SUN VALLEY
Jun 19, 3:46 PM MDTFLASH FLOOD3 Nw Cheyenne, WYBASEMENT FLOODING.

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, 9.2 hours before the alert went out and 195 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 2011-06-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 330 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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 2011-06-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 100 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
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.

694 
WGUS55 KCYS 192111
FFWCYS
WYC021-200300-
/O.NEW.KCYS.FF.W.0006.110619T2111Z-110620T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  LARAMIE COUNTY IN SOUTHEAST WYOMING...

* UNTIL 900 PM MDT

* AT 309 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE      
  WARNED AREA. RADAR ESTIMATED RAINFALL FROM WEATHER SERVICE RADAR   
  IS SHOWING THAT HOURLY RAINFALL AMOUNTS UP TO AN INCH AND A HALF   
  ARE POSSIBLE.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  CHEYENNE...ALBIN...BURNS...CARPENTER...FEDERAL...GUN BARREL...
  MERIDEN REST AREA...NORTH CHEYENNE...PINE BLUFFS...WARREN AF BASE
  AND WHITAKER.

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 10509 4155 10517 4156 10408 4100 10406

$$

CLAYCOMB
2 follow-up statements
093 
WGUS75 KCYS 192306
FFSCYS

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

WYC021-200300-
/O.CON.KCYS.FF.W.0006.000000T0000Z-110620T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LARAMIE WY-
506 PM MDT SUN JUN 19 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR EASTERN LARAMIE COUNTY
UNTIL 900 PM MDT...

AT 504 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. 
HOURLY ESTIMATED RAINFALL OBSERVED ON WEATHER SERVICE RADR AROUND AN 
INCH PER HOUR IS BEING OBSERVED ACROSS EASTERN PORTIONS OF LARAMIE 
COUNTY.

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
ALBIN...BURNS...CARPENTER...GUN BARREL AND MERIDEN REST AREA.

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.

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 4101 10458 4155 10467 4156 10408 4100 10406

$$

CLAYCOMB
881 
WGUS75 KCYS 200240
FFSCYS

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

WYC021-200255-
/O.CAN.KCYS.FF.W.0006.000000T0000Z-110620T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LARAMIE WY-
840 PM MDT SUN JUN 19 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR EASTERN LARAMIE
COUNTY 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 4101 10458 4155 10467 4156 10408 4100 10406

$$

CLAYCOMB

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 3:03 PM MDTSevere Thunderstorm WarningCYSLaramie42 min
Jun 19, 3:43 PM MDTSevere Thunderstorm WarningCYSLaramie33 min

Nearby

Flash Flood Warnings in Wyoming, 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.