Alert archive / Oklahoma / Flash Flood Warnings in 2001

Flash Flood Warning 8, NWS Amarillo, TX

September 20, 2001Beaver County, Oklahoma

NWS Amarillo, TX issued this flash flood warning at Sep 20, 2001, 8:20 PM CDT for Beaver County, Oklahoma. 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
Sep 20, 2001, 8:20 PM CDT (01:20 UTC)
Expired
Sep 20, 2001, 11:15 PM CDT
In force
3 hr
Issued by
NWS Amarillo, TX
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Beaver County, OK

The radar

The Dodge City radar (KDDC), 109 km from the middle of the area, began a volume at 01:24 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

Dodge City, (KDDC), launched 00:00Z, 1.3 hours before the alert went out and 112 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, Dodge City, at 00:00Z on 2001-09-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 488 joules per kilogram.LCLLFCEL10008507005003002001001 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, Dodge City, at 00:00Z on 2001-09-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 33 square meters per square second.1939Sfc1 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
488 J/kg
Mixed-layer CIN
-205 J/kg
Mixed-layer LCL
2154 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
33 m²/s²
0-3 km storm-relative helicity
67 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 
WGUS54 KAMA 210120
FFWAMA
FFWAMA
OKC007-210415-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AMARILLO TX
820 PM CDT THU SEP 20 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  BEAVER COUNTY IN THE OKLAHOMA PANHANDLE

* UNTIL 1115 PM CDT

* AT 820 PM CDT...WEATHER SERVICE RADAR ESTIMATED 1 1/2 TO 2 INCHES  
  OF RAIN HAD FALLEN ACROSS EASTERN BEAVER COUNTY. DOPPLER RADAR     
  INDICATED VERY HEAVY RAINFALL WILL CONTINUE TO MOVE ACROSS EASTERN 
  BEAVER COUNTY. THESE STORMS WILL MOVE SLOWLY SOUTHWEST AT 5 MPH    
  PRODUCING UP TO 2 INCHES OF RAIN OVER THE NEXT COUPLE OF HOURS.

* SOME LOCATIONS AFFECTED INCLUDE...
  BEAVER...ELMWOOD...FORGAN...GATE...KNOWLES...MOCANE AND SLAPOUT

PEOPLE LIVING IN LOW LYING AREAS SHOULD SEEK HIGHER GROUND IF 
FLOODING IS OBSERVED.

LAT...LON 3699 10000 3700 10054 3651 10055 3651 10002

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 Amarillo, TX wrote its last area forecast discussion before this flash flood warning went out at Sep 20, 2:37 PM CDT, 5 hours 43 minutes earlier.

Area forecast discussion, Sep 20, 2:37 PM CDT, 5 hours 43 minutes before
TEXAS/OKLAHOMA PANHANDLES FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
237 PM CDT THU SEP 20 2001

THE MAIN FORECAST DIFFICULTY WILL BE PRECIPITATION AND TEMPERATURES.
SURFACE ANALYSIS SHOWED A WEAK DRYLINE IN PLACE ACROSS THE
PANHANDLES FROM THE NORTHCENTRAL ZONE EXTENDING SOUTHWEST. A LOW
PRESSURE TROUGH WAS DRAPED ACROSS THE REGION WITH A SHORTWAVE
EMBEDDED IN NORTHWEST FLOW OVER NORTHEASTERN NEW MEXICO. AS THIS
SHORTWAVE PUSHES SOUTHEAST THIS AFTERNOON THUNDERSTORMS WILL
INITIATE ALONG THE DRYLINE. WITH A VERY UNSTABLE AIR MASS ACROSS
THE CENTRAL AND EASTERN ZONES...SEVERE THUNDERSTORMS WILL BE
POSSIBLE TONIGHT ESPECIALLY AS THE LOW-LEVEL JET DEVELOPS TO THE
SOUTHEAST THIS EVENING. A COLD FRONT PUSHING SOUTH ACROSS WESTERN
KANSAS AND EASTERN COLORADO WILL PUSH THROUGH THE FORECAST AREA
TONIGHT BUT MAY HANG UP OVER THE SOUTHERN ZONES FRIDAY. THIS WILL
COOL TEMPERATURES DOWN ABOUT 10 DEGREES COMPARED TO TODAYS
TEMPERATURES. PLENTY OF LOW-LEVEL MOISTURE WILL STILL BE IN PLACE...
HOWEVER ANTICYCLONIC FLOW ALOFT WITH SUBSIDENCE BEHIND AN EXITING
SHORTWAVE COULD LIMIT CONVECTION IN THE EASTERN AND CENTRAL ZONES
FRIDAY AFTERNOON AND EVENING. HOWEVER...ADDITIONAL VORT MAX ENERGY
SHOULD DEVELOP OVER THE MOUNTAINS AND PUSH INTO THE WESTERN HIGH
PLAINS FRIDAY NIGHT. THIS WILL HELP SUSTAIN MOUNTAIN STORMS OVERNIGHT
BRINGING A CHANCE OF PRECIPITATION TO THE WESTERN ZONES AND POSSIBLY
INTO THE CENTRAL ZONES FRIDAY NIGHT. NORTHWEST FLOW CONTINUES
SATURDAY WITH ADDITIONAL SHORTWAVE ACTIVITY POSSIBLE. WITH RETURN
FLOW AND A LEE TROUGH SETTING UP...ADDITIONAL STORMS MAY DEVELOP
ACROSS THE FORECAST AREA.

FOR THE LATER PERIODS...MEDIUM RANGE MODELS CONTINUE THE NORTHWEST
FLOW SUNDAY USHERING DOWN A COLD FRONT ACROSS THE AREA. IF THIS
HAPPENS...COLD AIR ADVECTION WOULD INCREASE. IN ADDITION...THE
MODELS AMPLIFY A RIDGE IN THE SOUTHWESTERN STATES MONDAY. WITH
NORTHERLY WINDS ALOFT RESULTING...MOUNTAIN CONVECTION WOULD HUG THE
MOUNTAINS MONDAY AND TUESDAY...REDUCING THE LIKELIHOOD OF
PRECIPITATION IN THE PANHANDLES. SURFACE HIGH PRESSURE BEHIND THE
FRONT WOULD LOWER TEMPERATURES TEMPERATURES DURING THE EARLY PART OF
THE WEEK WITH A GRADUAL WARM UP POSSIBLE BY MID WEEK.

PRELIM CCF...
AMA 59/83 60/86 58 322
DHT 56/81 57/84 55 123

.AMA...
TX...NONE.
OK...NONE.

CB

The office that day

Everything else NWS Amarillo, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 20, 8:03 PM CDTSevere Thunderstorm WarningAMABeaver87 min

Nearby

Flash Flood Warnings in Oklahoma, 2001Every 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.