Alert archive / Texas / Flash Flood Warnings in 2001

Flash Flood Warning 77, NWS Austin/San Antonio, TX

September 5, 2001Bexar County, Comal County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Sep 5, 2001, 6:49 PM CDT for Bexar County, Comal County, Texas. It was in force for 2 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 5, 2001, 6:49 PM CDT (23:49 UTC)
Expired
Sep 5, 2001, 9:00 PM CDT
In force
2 hr
Issued by
NWS Austin/San Antonio, TX
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Bexar County, TX, Comal County, TX

The radar

The Austin/San Antonio radar (KEWX), 43 km from the middle of the area, began a volume at 23:52 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

Del Rio, TX (KDRT), launched 12:00Z, 11.8 hours before the alert went out and 232 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, Del Rio, TX at 12:00Z on 2001-09-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 392 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, Del Rio, TX at 12:00Z on 2001-09-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 121 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
392 J/kg
Mixed-layer CIN
-126 J/kg
Mixed-layer LCL
1047 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
121 m²/s²
0-3 km storm-relative helicity
143 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

000 
WGUS54 KEWX 052349
FFWSAT
FFWSAT
TXC029-091-060200-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
649 PM CDT WED SEP 5 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* FLASH FLOOD WARNING FOR THE FOLLOWING COUNTIES IN TEXAS...
  COMAL
  BEXAR

* UNTIL 9 PM CDT

* AT 649 PM...WEATHER SERVICE DOPPLER RADAR INDICATED A LINE OF 
  THUNDERSTORMS WITH VERY HEAVY RAINFALL FROM DEVINE TO 
  BLANCO...MOVING EAST AT 20 MPH. RAINFALL RATES OF 2 TO 3 INCHES
  PER HOUR CAN BE EXPECTED WITH THIS LINE.

WITH ALREADY SATURATED GROUNDS...EXCESSIVE RUNOFF FROM THIS STORM 
WILL CAUSE FLASH FLOODING OF SMALL CREEKS AND STREAMS...HIGHWAYS AND 
UNDERPASSES. ADDITIONALLY...COUNTRY ROADS AND FARMLANDS ALONG THE 
BANKS OF CREEKS AND STREAMS AND OTHER LOW LYING AREAS ARE SUBJECT TO 
FLASH FLOODING.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS 
IMMINENT. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT 
ATTEMPT TO CROSS BRIDGES...DIPS...OR OTHER LOW SPOTS IF WATER COVERS 
THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL 
ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP TO HIGHER GROUND. BE 
ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE 
DANGERS OF FLOODS AND FLASH FLOODS.  
 

LAT...LON 2965 9881 2928 9876 2917 9845 2947 9818
          2957 9838 2964 9832 2983 9806 3000 9830

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 Austin/San Antonio, TX wrote its last area forecast discussion before this flash flood warning went out at Sep 5, 2:40 PM CDT, 4 hours 9 minutes earlier.

Area forecast discussion, Sep 5, 2:40 PM CDT, 4 hours 9 minutes before
SOUTH CENTRAL TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
240 PM CDT WED SEP 5 2001

SINCE MUCH OF THE HILL COUNTRY HAS NOT HAD THE RAINFALL TOTALS THAT
THE REST OF THE CWA HAS HAD THIS PAST WEEK...DECIDED NOT TO INCLUDE
THEM IN THE FLASH FLOOD WATCH EXTENSION PLANNED FOR TONIGHT.  WILL
WORD THE FORECAST WITH LOCALLY HEAVY RAINFALL HOWEVER.  UPPER LOW
APPEARS TO BE MOVING OUT OF CWA THURSDAY WITH UPPER RIDGE BUILDING
BACK OVER AREA.  REINTRODUCED POPS BACK INTO FORECAST AFTER FRIDAY
AND SATURDAY DRIER WEATHER.

.PRELIMINARY NUMBERS...
AUS 72/88/72/90 6521
DRT 72/90/72/92 4311
SAT 72/89/72/91 6521

.EWX...FLASH FLOOD WATCH SOUTH CENTRAL TEXAS TONIGHT.

The office that day

Everything else NWS Austin/San Antonio, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 5, 9:33 AM CDTFlash Flood WarningEWXLavaca4 hr
Sep 5, 12:23 PM CDTFlash Flood WarningEWXDeWitt, Gonzales3 hr
Sep 5, 12:41 PM CDTFlash Flood WarningEWXCaldwell, Comal, Guadalupe, Hays, Travis, Williamson3 hr
Sep 5, 12:59 PM CDTFlash Flood WarningEWXLavaca3 hr
Sep 5, 1:34 PM CDTFlash Flood WarningEWXKarnes3 hr
Sep 5, 1:51 PM CDTFlash Flood WarningEWXReal3 hr
Sep 5, 2:44 PM CDTFlash Flood WarningEWXBastrop, Fayette, Lee3 hr
Sep 5, 2:50 PM CDTFlash Flood WarningEWXWilson115 min
Sep 5, 3:01 PM CDTFlash Flood WarningEWXBandera, Kerr3 hr
Sep 5, 3:21 PM CDTFlash Flood WarningEWXComal, Gonzales, Guadalupe3 hr
Sep 5, 4:39 PM CDTFlash Flood WarningEWXKarnes, Wilson4 hr
Sep 5, 5:29 PM CDTFlash Flood WarningEWXBlanco, Kendall3 hr
Sep 5, 5:57 PM CDTFlash Flood WarningEWXBandera2 hr
Sep 5, 6:03 PM CDTFlash Flood WarningEWXMedina2 hr

Nearby

Flash Flood Warnings in Texas, 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.