Alert archive / Texas / Flash Flood Warnings in 2012

Flash Flood Warning 14, NWS Austin/San Antonio, TX

February 4, 2012Hays County, Travis County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Feb 4, 2012, 2:42 AM CST for Hays County, Travis County, Texas. It was in force for 3 hr. 1 report 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: Feb 4, 2012, 2:42 AM CST (08:42 UTC)
Expired: Feb 4, 2012, 5:30 AM CST
In force: 3 hr
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon
Flood severity: None

Counties Hays County, TX, Travis County, TX

The radar

The Austin/San Antonio radar (KEWX), 50 km from the middle of the area, began a volume at 08:43 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
Feb 4, 3:30 AM CST	FLASH FLOOD	3 Ese Wimberley, TX	SPOKE HOLLOW AND HIDDEN VALLEY LOW WATER CROSSING IN HAYS COUNTY CLOSED DUE TO WATER OVER THE ROAD.

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, 8.7 hours before the alert went out and 276 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: 2376 J/kg
Mixed-layer CIN: -24 J/kg
Mixed-layer LCL: 706 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 99 m²/s²
0-3 km storm-relative helicity: 145 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 6.5

Open this sounding in Storm Lab

The text

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

738 
WGUS54 KEWX 040842
FFWEWX
TXC209-453-041130-
/O.NEW.KEWX.FF.W.0014.120204T0842Z-120204T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
242 AM CST SAT FEB 4 2012

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL HAYS COUNTY...
  CENTRAL TRAVIS COUNTY...

* UNTIL 530 AM CST.

* AT 242 AM CST...NATIONAL WEATHER SERVICE METEOROLOGISTS HAVE 
  DETERMINED THAT SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL
  WILL LIKELY PRODUCE FLASH FLOODING ACROSS MUCH OF HAYS AND TRAVIS 
  COUNTIES. DOPPLER RADAR ESTIMATES SUGGEST THAT EXPECTED RAINFALL 
  AMOUNTS COULD REACH 3 TO 5 INCHES BY 4 AM.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  AUSTIN...DRIPPING SPRINGS...TANGLEWOOD FOREST...WIMBERLEY...BUDA...
  DRIFTWOOD...KYLE...ONION CREEK...ROLLINGWOOD...WEST LAKE HILLS AND
  WOODCREEK.

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 3041 9774 3014 9774 2990 9790 2999 9822
      3004 9828 3014 9823

$$

1 follow-up statement

415 
WGUS74 KEWX 040955
FFSEWX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
355 AM CST SAT FEB 4 2012

TXC209-453-041130-
/O.CON.KEWX.FF.W.0014.000000T0000Z-120204T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
HAYS TX-TRAVIS TX-
355 AM CST SAT FEB 4 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 AM CST FOR
CENTRAL TRAVIS AND CENTRAL HAYS COUNTIES...

AT 348 AM CST...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED TO 
DETECT AREAS OF RAIN AND A FEW THUNDERSTORMS MOVING OVER THE WARNED 
AREAS OF HAYS AND TRAVIS COUNTIES. WHILE THE HEAVIEST RAINS HAVE 
SHIFTED EAST OF THE WARNED AREA...ADDITIONAL RAINS UP TO HALF AN 
INCH ARE POSSIBLE...AND CREEKS...STREAMS AND POOR DRAINAGE AREAS 
WILL LIKELY REMAIN FLOODED ACROSS MANY LOCATIONS THROUGH AT LEAST 5 
AM. 

LOCATIONS IN THE WARNING AREA INCLUDE DRIPPING SPRINGS...DRIFTWOOD...
WEST LAKE HILLS...TANGLEWOOD FOREST...ROLLINGWOOD...ONION CREEK AND
AUSTIN.

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 3041 9774 3014 9774 2990 9790 2999 9822
      3004 9828 3014 9823

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 3, 9:18 PM CST	Areal Flood Advisory	EWX	Bexar	2 hr
Feb 3, 9:45 PM CST	Areal Flood Advisory	EWX	Williamson	105 min
Feb 3, 10:02 PM CST	Flash Flood Warning	EWX	Bexar	118 min
Feb 3, 10:15 PM CST	Severe Thunderstorm Warning	EWX	Bexar	30 min
Feb 3, 10:36 PM CST	Flash Flood Warning	EWX	Williamson	114 min
Feb 3, 10:38 PM CST	Severe Thunderstorm Warning	EWX	Bexar	37 min
Feb 3, 10:51 PM CST	Flash Flood Warning	EWX	Bexar	3 hr
Feb 3, 11:15 PM CST	Severe Thunderstorm Warning	EWX	Bexar, Guadalupe	60 min
Feb 4, 12:15 AM CST	Severe Thunderstorm Warning	EWX	Bexar, Guadalupe, Wilson	45 min
Feb 4, 12:57 AM CST	Areal Flood Advisory	EWX	Burnet	2 hr
Feb 4, 1:07 AM CST	Areal Flood Advisory	EWX	Hays, Travis	113 min
Feb 4, 1:25 AM CST	Flash Flood Warning	EWX	Travis, Williamson	3 hr
Feb 4, 1:54 AM CST	Areal Flood Advisory	EWX	Bexar, Guadalupe, Wilson	2 hr
Feb 4, 2:32 AM CST	Areal Flood Advisory	EWX	Bandera, Medina	118 min
Feb 4, 3:11 AM CST	Areal Flood Advisory	EWX	Bandera, Bexar, Medina	109 min
Feb 4, 3:27 AM CST	Areal Flood Advisory	EWX	Bastrop, Caldwell, Hays, Lee, Travis	2 hr
Feb 4, 4:06 AM CST	Areal Flood Advisory	EWX	Bexar, Comal, Guadalupe	114 min

Nearby

Flash Flood Warnings in Texas, 2012 Every 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.