Alert archive / Wyoming / Flash Flood Warnings in 2008

Flash Flood Warning 2, NWS Cheyenne, WY

May 22, 2008Platte County, Wyoming

NWS Cheyenne, WY issued this flash flood warning at May 22, 2008, 5:15 PM MDT for Platte County, Wyoming. It was in force for 6 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
May 22, 2008, 5:15 PM MDT (23:15 UTC)
Expired
May 22, 2008, 10:53 PM MDT
In force
6 hr
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Flood severity
None

County Platte County, WY

The radar

The Cheyenne radar (KCYS), 111 km from the middle of the area, began a volume at 23:16 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

Rapid City, SD (KUNR), launched 12:00Z, 11.3 hours before the alert went out and 278 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, Rapid City, SD at 12:00Z on 2008-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Rapid City, SD at 12:00Z on 2008-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 69 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
614 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
69 m²/s²
0-3 km storm-relative helicity
190 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 222322
FFWCYS
WYC031-230315-
/O.NEW.KCYS.FF.W.0002.080522T2315Z-080523T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
515 PM MDT THU MAY 22 2008

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL PLATTE COUNTY IN SOUTHEAST WYOMING...

* UNTIL 915 PM MDT

* AT 511 PM MDT...THE PLATTE COUNTY SHERIFFS OFFICE REPORTED THAT 
RECENT HEAVY RAINFALL HAS WASHED OUT A PORTION OF FISH CREEK ROAD 
TO THE NORTHWEST OF WHEATLAND.  

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO I-25 MM 87
AND MUCH OF FISH CREEK NORTHWEST OF WHEATLAND.  

ADDITIONAL RAINFALL AMOUNTS OF ONE HALF INCH ARE LIKELY EARLY THIS
EVENING OVER CENTRAL PLATTE COUNTY FROM STRONG THUNDERSTORMS.  THE
ADDITIONAL RAINFALL WILL KEEP WATER LEVELS HIGH WITH FLASH FLOODING
LIKELY CONTINUING ALONG FISH CREEK.

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.

REPORT FLOODING TO THE NATIONAL WEATHER SERVICE OFFICE IN CHEYENNE AT
1-800-269-6220.

LAT...LON 4218 10517 4223 10488 4208 10488 4201 10513
TIME...MOT...LOC 2315Z 180DEG 0KT 4204 10494

$$

WEILAND
3 follow-up statements
000
WGUS75 KCYS 230053
FFSCYS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
653 PM MDT THU MAY 22 2008

WYC031-230315-
/O.CON.KCYS.FF.W.0002.000000T0000Z-080523T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PLATTE WY-
653 PM MDT THU MAY 22 2008

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 915 PM MDT FOR
WESTERN AND NORTHERN PLATTE COUNTY...

AT 640 PM MDT...THE PLATTE COUNTY SHERIFFS OFFICE REPORTED THAT THE
RECENT HEAVY RAINFALL HAS PRODUCED 4 TO 6 INCHES OF WATER FLOWING 
OVER MANY ROADS WEST OF WHEATLAND...AROUND WHEATLAND AS WELL AS THE
NORTH PART OF PLATTE COUNTY.  SOME ROADS HAVE BEEN CLOSED DUE TO
THE WATER FLOWING OVER THE ROADS AND A PORTION OF FISH CREEK ROAD
WAS WASHED OUT LATE THIS AFTERNOON.  TWO TO THREE FEET OF WATER WAS
ALSO FLOWING OVER PLEASANT VALLEY ROAD IN GUERNSEY.   

IN ADDITION...THE LARAMIE RIVER AND NORTH LARAMIE RIVER HAVE JUST WENT 
OUT OF THEIR BANKS WITH LOCAL LOW LAND FLOODING TAKING PLACE.

RAINFALL RATES AND COVERAGE OF THUNDERSTORMS WILL GRADUALLY DIMINISH
THROUGH EARLY TONIGHT IN PLATTE COUNTY.  HOWEVER...THE WATER LEVELS 
WILL REMAIN HIGH FOR MOST OF THE REST OF TONIGHT.    

A SEVERE THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL 900 PM MDT
THURSDAY EVENING FOR CENTRAL NEBRASKA AND SOUTHEAST WYOMING.

LAT...LON 4218 10517 4223 10488 4208 10488 4201 10513
TIME...MOT...LOC 0041Z 180DEG 0KT 4201 10491

$$

WEILAND
000 
WGUS55 KCYS 230258
FFWCYS
WYC031-230715-
/O.EXT.KCYS.FF.W.0002.000000T0000Z-080523T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
844 PM MDT THU MAY 22 2008

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  WESTERN AND NORTHERN PLATTE COUNTY IN SOUTHEAST WYOMING...

* UNTIL 115 AM MDT

* AT 842 PM MDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED FLOODING
  FROM EARLIER HEAVY RAINFALL OVER THE AREA.  IN ADDITION...STRONG
  THUNDERSTORMS WILL CONTINUE OVER MUCH OF PLATTE COUNTY THROUGH 
  EARLY FRIDAY MORNING AND WILL AGGRAVATE THE EXISTING FLOODING.

* LOCATIONS IN THE WARNING INCLUDE ALL OF WESTERN AND NORTHERN PLATTE
  COUNTY...INCLUDING THE CITIES OF WHEATLAND...GLENDO AND GUERNSEY.
  
ADDITIONAL RAINFALL AMOUNTS OF UP TO AN INCH OF RAIN IN A SHORT TIME ARE
POSSIBLE IN PLATTE COUNTY THROUGH EARLY FRIDAY MORNING.  AS OF 840 PM...
FISH CREEK NORTHWEST OF WHEATLAND WAS NEAR BANKFULL AND THE LARAMIE
AND NORTH LARAMIE RIVERS ARE OUT OF THEIR BANKS AND CAUSING FLOODING OF
LOW LYING AGRICULTURAL AREAS.  WATER WAS STILL FLOWING OVER MANY ROADS 
WEST OF WHEATLAND AND IN THE GUERNSEY AREA.  

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF
STREAMS...COUNTRY ROADS...NORMALLY DRY WASHES...AS WELL AS LOW LYING
AREAS ALONG THE BANKS OF STREAMS.

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. MOVE TO HIGHER GROUND.

REPORT FLOODING TO THE NATIONAL WEATHER SERVICE OFFICE IN CHEYENNE AT
1-800-269-6220.

LAT...LON 4218 10517 4223 10488 4208 10488 4201 10513
TIME...MOT...LOC 0244Z 180DEG 0KT 4201 10491

$$

WEILAND
000
WGUS75 KCYS 230453
FFSCYS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
1049 PM MDT THU MAY 22 2008

WYC031-230459-
/O.CAN.KCYS.FF.W.0002.000000T0000Z-080523T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
PLATTE WY-
1049 PM MDT THU MAY 22 2008

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR WESTERN AND NORTHERN
PLATTE COUNTY...

THE RAINFALL RATES HAVE TAPERED OFF SOME LATE THIS EVENING OVER PLATTE
COUNTY AS THE SHOWERS AND THUNDERSTORMS GRADUALLY WEAKEN.  THE THREAT
FOR FLASH FLOODING HAS ENDED OVER THE COUNTY.  HOWEVER...FLOODING 
WILL CONTINUE OVER THE WEST AND NORTH PARTS OF THE COUNTY THE REST OF
TONIGHT AND FRIDAY.  THE FLASH FLOOD WARNING WILL BE REPLACED BY A
FLOOD WARNING WHICH WILL BE IN EFFECT THROUGH FRIDAY. 

LAT...LON 4218 10517 4223 10488 4208 10488 4201 10513
TIME...MOT...LOC 0449Z 180DEG 0KT 4201 10491

$$

WEILAND

The office that day

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

IssuedProductOfficeCountiesLasted
May 21, 6:10 PM MDTSevere Thunderstorm WarningCYSAlbany, Converse, Platte50 min
May 21, 6:20 PM MDTAreal Flood AdvisoryCYSAlbany, Converse96 min
May 21, 7:02 PM MDTSevere Thunderstorm WarningCYSPlatte43 min
May 21, 8:28 PM MDTAreal Flood AdvisoryCYSPlatte90 min
May 22, 7:58 AM MDTDense Fog AdvisoryCYS2 hr
May 22, 9:15 AM MDTAreal Flood AdvisoryCYSPlatte4 hr
May 22, 10:18 AM MDTDense Fog AdvisoryCYS102 min
May 22, 12:31 PM MDTFlash Flood WatchCYSWeston11 hr
May 22, 12:58 PM MDTSevere Thunderstorm WarningCYSAlbany, Laramie47 min
May 22, 1:14 PM MDTTornado WarningCYSAlbany31 min
May 22, 1:44 PM MDTTornado WarningCYSAlbany31 min
May 22, 2:07 PM MDTTornado WarningCYSAlbany23 min
May 22, 2:14 PM MDTSevere Thunderstorm WarningCYSGoshen, Laramie31 min
May 22, 2:15 PM MDTTornado WarningCYSAlbany, Carbon30 min
May 22, 2:26 PM MDTFlash Flood WarningCYSAlbany4 hr
May 22, 2:29 PM MDTTornado WarningCYSAlbany31 min
May 22, 3:11 PM MDTTornado WarningCYSAlbany, Laramie34 min
May 22, 3:27 PM MDTTornado WarningCYSLaramie33 min
May 22, 4:00 PM MDTSevere Thunderstorm WarningCYSLaramie45 min
May 22, 5:00 PM MDTAreal Flood AdvisoryCYSLaramie2 hr
May 22, 5:16 PM MDTSevere Thunderstorm WarningCYSAlbany, Converse, Platte44 min
May 22, 5:32 PM MDTFlash Flood WarningCYSPlatte66 min

Nearby

Flash Flood Warnings in Wyoming, 2008Every flash flood warning in 2008

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.