Alert archive / Wyoming / Flash Flood Warnings in 2002

Flash Flood Warning 3, NWS Cheyenne, WY

August 27, 2002Carbon County, Wyoming

NWS Cheyenne, WY issued this flash flood warning at Aug 27, 2002, 4:14 PM MDT for Carbon County, Wyoming. It was in force for 3 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: Aug 27, 2002, 4:14 PM MDT (22:14 UTC)
Expired: Aug 27, 2002, 7:15 PM MDT
In force: 3 hr
Issued by: NWS Cheyenne, WY
Area: Counties, with a storm outline in the text

County Carbon County, WY

The radar

The Cheyenne radar (KCYS), 183 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.

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 10.2 hours before the alert went out and 187 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: 18 J/kg
Mixed-layer CIN: -182 J/kg
Mixed-layer LCL: 1237 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 63 m²/s²
0-3 km storm-relative helicity: 83 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
WGUS55 KCYS 272214
FFWCYS
WYC007-280115-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
415 PM MDT TUE AUG 27 2002

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN CARBON COUNTY IN SOUTH CENTRAL WYOMING

* UNTIL 715 PM MDT

* AT 405 PM MDT...RADAR INDICATED THUNDERSTORMS WITH VERY HEAVY
  RAINFALL WERE OVER NORTHEASTERN CARBON COUNTY...OR ABOUT 35
  MILES SOUTH OF CASPER...MOVING LITTLE.

RADAR INDICATED FROM FOUR TO FIVE INCHES OF RAIN MAY HAVE FALLEN
FROM 200 TO 400 PM IN AN AREA BETWEEN HIGHWAYS 487 AND 77 ABOUT
30 MILES NORTH OF HANNA.  THE VERY HEAVY RAINFALL IS OVER THE
MUDDY CREEK DRAINAGE.  

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AND NORMALLY DRY WASHES...AS
WELL AS FARMLAND ALONG THE BANKS OF CREEKS AND STREAMS.

DO NOT DRIVE THROUGH FLOWING WATER. NEARLY HALF OF ALL FLOOD
FATALITIES ARE VEHICLE RELATED. AS LITTLE AS 6 INCHES OF WATER MAY
CAUSE YOU TO LOSE CONTROL OF YOUR VEHICLE. TWO FEET OF RUSHING WATER
CAN CARRY AWAY MOST VEHICLES INCLUDING SUVS AND PICKUPS.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NEAREST NATIONAL WEATHER SERVICE.

LAT...LON 4235 10649 4222 10632 4222 10610 4244 10611 4243 10652

&&

COX

WCJIN-WYSE

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 26, 10:24 PM MDT	Severe Thunderstorm Warning	CYS	Platte	51 min
Aug 26, 10:50 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	40 min
Aug 26, 11:15 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	46 min
Aug 26, 11:31 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	44 min
Aug 27, 5:29 PM MDT	Severe Thunderstorm Warning	CYS	Carbon	46 min

Nearby

Flash Flood Warnings in Wyoming, 2002 Every flash flood warning in 2002

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.