Alert archive / Wyoming / Flash Flood Warnings in 2001

Flash Flood Warning 3, NWS Riverton, WY

July 10, 2001Johnson County, Wyoming

NWS Riverton, WY issued this flash flood warning at Jul 10, 2001, 10:45 PM MDT for Johnson 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 the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Jul 10, 2001, 10:45 PM MDT (04:45 UTC)
Expired: Jul 11, 2001, 1:45 AM MDT
In force: 3 hr
Issued by: NWS Riverton, WY
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Johnson County, WY

The radar

The Riverton/Lander radar (KRIW), 170 km from the middle of the area, began a volume at 04:49 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 00:00Z, 4.8 hours before the alert went out and 164 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: 188 J/kg
Mixed-layer CIN: -52 J/kg
Mixed-layer LCL: 2360 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 16 m²/s²
0-3 km storm-relative helicity: 48 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 KRIW 110449
FFWRIW

WYC019-110745-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE RIVERTON WY
1045 PM MDT TUE JUL 10 2001

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN JOHNSON COUNTY IN NORTH CENTRAL WYOMING

* UNTIL 145 AM MDT

* AT 1045 PM MDT...A TRAINED WEATHER SPOTTER REPORTED A FLASH FLOOD  
10 MILES NORTH AND 6 MILES EAST OF KAYCEE ALONG RENO ROAD.  DOPPLER 
RADAR INDICATED WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS OVER 
SOUTHERN JOHNSON COUNTY MOVING SLOWLY NORTHEAST AT 10 TO 15 MPH.

EXCESSIVE RUNOFF FROM THESE SHOWERS AND STORMS WILL CAUSE FLASH FLOODING 
OF STREAMS...COUNTRY ROADS...NORMALLY DRY WASHES...AS WELL AS 
FARMLAND ALONG THE BANKS OF STREAMS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IT IS NEARLY IMPOSSIBLE AT NIGHT TO TELL THE
DEPTH OF WATER ON ROADWAYS. NEVER DRIVE THROUGH WATER OF UNKNOWN
DEPTH.

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



LAT...LON 4406 10710 4354 10705 4355 10607 4407 10606

STASSER

WCJIN-WYNE

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Riverton, WY wrote its last area forecast discussion before this flash flood warning went out at Jul 10, 2:30 PM MDT, 8 hours 15 minutes earlier.

Area forecast discussion, Jul 10, 2:30 PM MDT, 8 hours 15 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
230 PM MDT TUE JUL 10 2001

WV SATL LOOP SHOWS SOME DISTINCT WX FEATURES MOVG THRU THE ROCKIES
AND WRN U.S.  MODELS SEEM OK WITH THE WV MOVG N THRU THE ROCKIES.
ONE FRTHER W SEEMS TO BE POORLY HANDLED BY ETA/AVN BUT THIS FEATURE
NOT LIKELY TO BE A FACTOR IN CWA WX OUTCOME TNGT. WL USE SATL PICS
FOR FIRST PD PCPN COVRG AS CONVCTN FIRES UP. LEANING TWD SCT LWR
ELEVTNS AND LIKELY MTNS. LOW TEMPS NOT FAR FM PREV NT DUE TO HI
DEWPTS. ON WED THE FLOW IS PROGD MORE WSW IN THE 700-500MB LAYER DUE
TO CIRCULTN OVR MT. STILL PLENTY OF MSTR ARND SO WOULD EXPECT SCT
POPS MTNS AND LOW SCT POPS LWR ELVTNS. NOT MUCH CHG IN HI TEMPS FM
TDY DUE TO CLDS/PCPN. WL KEEP LOW EVE POPS IN WED NT WITH MILD LOWS.
ON THU ETA BRINGS SSW FLO BACK INTO CWA WITH AVN MORE WSW DUE POSTN
OF UPR HI IN NEW MEX VS ETA UPR HI POSTN FRTHER E. THUS ETA WETTER
THAN AVN AND WL USE PERSISTENCE AND SIDE WITH ETA. EXPECT HIGHS THURS
CLOSE TO WED. IN EXTNDD MRF/EC CLOSE TO PREV ONES. BIGGEST CHG IS THE
UPR LOW FORMATION OVER WA/OR AREA SUN NT INTO EARLY NEXT WEEK. THIS
AS ELONGATED UPR HI SETTLES INTO NM/AZ. THIS PUTS WY IN SW FLO VS SSW
FLOW. SOME DRYING HINTED FOR SAT BUT DOES HANG ON TO MSTR CENT/E CWA.
THEN IT SEEMS THINGS TRY TO DRY OUT FOR SUN/MON. WL KEEP MODRY FCST
SUN-TUE THINK UPR LO ADVANCEMENT FOR TUE TOO FAST AND WL NOT PLAY
COOLING INTO CWA TUE.

.RIW...NONE

AR@

In the hours before

Local storm report, Jul 10, 4:54 PM MDT, 5 hours 51 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RIVERTON, WY
454 PM MDT TUE JUL 10 2001

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0445 PM    KIRBY                     WY   1.00 INCH HAIL
07/10/01   HOT SPRINGS                    REPORTED BY SPOTTERS

0449 PM    WINCHESTER                WY   1.00 INCH HAIL
07/10/01   WASHAKIE                       REPORTED BY SPOTTERS

0445 PM    WINCHESTER                WY   1.75 INCH HAIL
07/10/01   WASHAKIE                       REPORTED BY SPOTTERS

0435 PM    4 EAST KIRBY              WY   FUNNEL CLOUD
07/10/01   HOT SPRINGS                    REPORTED BY
OTHERI

Nearby

Flash Flood Warnings in Wyoming, 2001 Every flash flood warning in 2001

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.