Alert archive / Wyoming / Flash Flood Warnings in 2011
Flash Flood Warning 12, NWS Cheyenne, WY
NWS Cheyenne, WY issued this flash flood warning at Jul 12, 2011, 5:36 PM MDT for 4 counties in Wyoming. It was in force for 3 hr. 9 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
- Jul 12, 2011, 5:36 PM MDT (23:36 UTC)
- Expired
- Jul 12, 2011, 8:30 PM MDT
- In force
- 3 hr
- Issued by
- NWS Cheyenne, WY
- Area
- Storm-based polygon
- Flood severity
- None
Counties Albany County, WY, Goshen County, WY, Laramie County, WY, Platte County, WY
The radar
The Cheyenne radar (KCYS), 31 km from the middle of the area, began a volume at 23:36 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 |
|---|---|---|---|
| Jul 12, 5:52 PM MDT | HEAVY RAIN 0.75 | 3 W Cheyenne, WY | FE WARREN AIRFORCE BASE |
| Jul 12, 5:56 PM MDT | FLASH FLOOD | Cheyenne, WY | 6 INCHES OF WATER AT THE INTERSECTION OF 19TH AND CAREY. |
| Jul 12, 5:57 PM MDT | FLASH FLOOD | Cheyenne, WY | PERSHING AND EVANS FLOODED AND WATER FLOWING FAST |
| Jul 12, 6:00 PM MDT | FLASH FLOOD | Cheyenne, WY | 4 TO 5 FEET OF WATER AT AMES AVE UNDERPASS. |
| Jul 12, 6:09 PM MDT | HEAVY RAIN 1 | 5 Ne Cheyenne, WY | MEASURED IN 60 MINUTES |
| Jul 12, 6:30 PM MDT | FLASH FLOOD | 6 Ne Cheyenne, WY | WATER OVER WHITNEY RD APPROXIMATELY 6 TO 8 INCHES DEEP AND 15FT ACROSS |
| Jul 12, 6:35 PM MDT | HEAVY RAIN 2 | 7 Ne Cheyenne, WY | MEASURED FROM 500PM TO 630PM |
| Jul 12, 6:36 PM MDT | FLASH FLOOD | 4 Ne Cheyenne, WY | 4 MILE ROAD AND STAGECOACH ROAD |
| Jul 12, 7:00 PM MDT | FLASH FLOOD | Cheyenne, WY | NEAR CAREY JUNIOR HIGH SCHOOL. TRAFFIC LIGHTS ARE OUR. HAIL COVERING GROUND. |
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, 11.6 hours before the alert went out and 220 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.
- Mixed-layer CAPE
- 1 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1730 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- -17 m²/s²
- 0-3 km storm-relative helicity
- 31 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
338 WGUS55 KCYS 122336 FFWCYS WYC001-015-021-031-130230- /O.NEW.KCYS.FF.W.0012.110712T2336Z-110713T0230Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE CHEYENNE WY 536 PM MDT TUE JUL 12 2011 THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A * FLASH FLOOD WARNING FOR... EXTREME EAST CENTRAL ALBANY COUNTY IN SOUTHEAST WYOMING... SOUTHERN PLATTE COUNTY IN SOUTHEAST WYOMING... SOUTHWESTERN GOSHEN COUNTY IN SOUTHEAST WYOMING... WESTERN LARAMIE COUNTY IN SOUTHEAST WYOMING... * UNTIL 830 PM MDT * AT 534 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. RADAR ESTIMATED RAINFALL OF 1 TO 1.5 INCHES ALONG WITH HEAVY HAIL ACCUMULATIONS WILL CAUSE FLASH FLOODING IN THE CITY OF CHEYENNE. * RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE... CHEYENNE...CRYSTAL LAKE RESERVOIR...FEDERAL...GRANITE SPRINGS RESERVOIR...HORSE CREEK...IRON MOUNTAIN...NORTH CHEYENNE...WARREN AF BASE AND WHITAKER. PRECAUTIONARY/PREPAREDNESS ACTIONS... TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN CHEYENNE. && LAT...LON 4171 10456 4104 10450 4103 10523 4168 10531 $$ CLAYCOMB
1 follow-up statement
964 WGUS75 KCYS 130221 FFSCYS FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE CHEYENNE WY 821 PM MDT TUE JUL 12 2011 WYC001-015-021-031-130236- /O.EXP.KCYS.FF.W.0012.000000T0000Z-110713T0230Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ GOSHEN WY-ALBANY WY-LARAMIE WY-PLATTE WY- 821 PM MDT TUE JUL 12 2011 ...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTHERN PLATTE... WESTERN LARAMIE...EXTREME EAST CENTRAL ALBANY AND SOUTHWESTERN GOSHEN COUNTIES WILL BE ALLOWED TO EXPIRE AT 830 PM MDT... EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS AND CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING TO RECEDE...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN OBSERVED... PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY. LAT...LON 4171 10456 4104 10450 4104 10524 4168 10531 $$ CLAYCOMB
The office that day
Everything else NWS Cheyenne, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 12, 12:07 PM MDT | Flash Flood Watch | CYS | Laramie | 18 hr |
| Jul 12, 5:27 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 63 min |
| Jul 12, 5:53 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 67 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.