Alert archive / Texas / Flash Flood Warnings in 2012

Flash Flood Warning 48, NWS Austin/San Antonio, TX

July 15, 2012Travis County, Williamson County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Jul 15, 2012, 12:40 AM CDT for Travis County, Williamson County, Texas. It was in force for 3 hr. 2 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 15, 2012, 12:40 AM CDT (05:40 UTC)
Expired
Jul 15, 2012, 3:30 AM CDT
In force
3 hr
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Flood severity
None

Counties Travis County, TX, Williamson County, TX

The radar

The Ft Hood radar (KGRK), 64 km from the middle of the area, began a volume at 05:42 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

TimeReportWhereRemark
Jul 15, 1:45 AM CDTFLASH FLOOD5 Ssw Jollyville, TXSPICEWOOD SPRINGS ROAD CLOSED BETWEEN OLD LAMPASAS AND LOOP 360 DUE TO FLOODING.
Jul 15, 1:52 AM CDTFLASH FLOOD5 Ssw Jollyville, TXOLD SPICEWOOD SPRINGS RD CLOSED DUE TO FLOODING

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 5.7 hours before the alert went out and 287 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, Corpus Christi, TX at 00:00Z on 2012-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1864 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, Corpus Christi, TX at 00:00Z on 2012-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 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
1864 J/kg
Mixed-layer CIN
-26 J/kg
Mixed-layer LCL
1009 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
23 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.

563 
WGUS54 KEWX 150540
FFWEWX
TXC453-491-150830-
/O.NEW.KEWX.FF.W.0048.120715T0540Z-120715T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1240 AM CDT SUN JUL 15 2012

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL TRAVIS COUNTY...
  SOUTHWESTERN WILLIAMSON COUNTY...

* UNTIL 330 AM CDT.

* AT 1238 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE      
  WARNED AREA. RADAR ESTIMATES TWO TO THREE INCHES OF RAIN HAS       
  FALLEN OVER THE WEST SIDE OF THE AUSTIN METRO AREA. ANOTHER ONE TO 
  TWO INCHES OF RAIN IS POSSIBLE WITHING THE NEXT TWO HOURS.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  ANDERSON MILL...AUSTIN...CEDAR PARK...TANGLEWOOD FOREST...BEE
  CAVE...LAKEWAY...MANSFIELD DAM...ONION CREEK...ROLLINGWOOD AND WEST
  LAKE HILLS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IT IS HARD TO RECOGNIZE THE DANGERS OF FLOODING AT NIGHT. IF FLOOD
WATERS RISE ACT QUICKLY. DO NOT STAY IN FLOOD PRONE AREAS.

&&

LAT...LON 3010 9776 3029 9804 3054 9787 3037 9759

$$
1 follow-up statement
340 
WGUS74 KEWX 150714
FFSEWX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
214 AM CDT SUN JUL 15 2012

TXC453-491-150830-
/O.CON.KEWX.FF.W.0048.000000T0000Z-120715T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
TRAVIS TX-WILLIAMSON TX-
214 AM CDT SUN JUL 15 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 AM CDT FOR
SOUTHWESTERN WILLIAMSON AND CENTRAL TRAVIS COUNTIES...

AT 207 AM CDT...LOCAL EMERGENCY MANAGEMENT OFFICIALS REPORTED FLASH 
FLOODING IN NORTHWESTERN AUSTIN. STORMS OVER THE AREA HAVE 
DISSIPATED. HOWEVER...RUNOFF FROM EARLY RAIN WILL CONTINUE SO WILL 
KEEP THE WARNING IN EFFECT TO ACCOUNT FOR THIS.

LOCATIONS IN THE WARNING AREA INCLUDE MANSFIELD DAM...LAKEWAY...CEDAR
PARK AND ANDERSON MILL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IT IS HARD TO RECOGNIZE THE DANGERS OF FLOODING AT NIGHT. IF FLOOD
WATERS RISE ACT QUICKLY. DO NOT STAY IN FLOOD PRONE AREAS.

&&

LAT...LON 3010 9776 3029 9804 3054 9787 3037 9759

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 15, 12:25 AM CDTAreal Flood AdvisoryEWXTravis, Williamson2 hr
Jul 15, 4:59 PM CDTAreal Flood AdvisoryEWXWilliamson2 hr
Jul 15, 5:18 PM CDTFlash Flood WarningEWXWilliamson2 hr
Jul 15, 6:03 PM CDTAreal Flood AdvisoryEWXTravis117 min
Jul 15, 6:31 PM CDTFlash Flood WarningEWXTravis3 hr
Jul 15, 6:40 PM CDTAreal Flood AdvisoryEWXBandera, Medina110 min

Nearby

Flash Flood Warnings in Texas, 2012Every flash flood warning in 2012

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.