Alert archive / Texas / Flash Flood Warnings in 2011

Flash Flood Warning 6, NWS Austin/San Antonio, TX

October 9, 2011Comal County, Hays County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Oct 9, 2011, 4:04 AM CDT for Comal County, Hays 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: Oct 9, 2011, 4:04 AM CDT (09:04 UTC)
Expired: Oct 9, 2011, 7:00 AM CDT
In force: 3 hr
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon
Flood severity: None

Counties Comal County, TX, Hays County, TX

The radar

The Austin/San Antonio radar (KEWX), 23 km from the middle of the area, began a volume at 09:03 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
Oct 9, 5:53 AM CDT	FLASH FLOOD	3 N Garden Ridge, TX	FLASH FLOODING CLOSED SCHOENTHALL RD AT THE 10200 BLOCK.

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, 9.1 hours before the alert went out and 249 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: 2637 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 842 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: -2 m²/s²
0-3 km storm-relative helicity: 14 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

327 
WGUS54 KEWX 090904
FFWEWX
TXC091-209-091200-
/O.NEW.KEWX.FF.W.0006.111009T0904Z-111009T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
404 AM CDT SUN OCT 9 2011

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  COMAL COUNTY...
  HAYS COUNTY...

* UNTIL 700 AM CDT.

* AT 401 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH INTENSE RAINFALL ACROSS COMAL AND HAYS
  COUNTIES. RAINFALL RATES OF 2 TO 3 INCHES PER HOUR CAN BE
  EXPECTED WITH THESE STORMS.   

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  CANYON LAKE DAM...DRIPPING SPRINGS...NEW BRAUNFELS...SAN MARCOS...
  WIMBERLEY...BUDA...BULVERDE...DRIFTWOOD...FISCHER...GARDEN RIDGE...
  HENLY...KYLE...NIEDERWALD...SPRING BRANCH...UHLAND AND WOODCREEK.

RAINFALL AMOUNTS OF BETWEEN 3 AND 4 INCHES WERE REPORTED IN THE
SAN ANTONIO AREA AS THESE SAME STORMS MOVED THROUGH.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

WHEN WATER COVERS THE ROAD...TURN AROUND DON'T DROWN. THE LIFE YOU
SAVE MAY BE YOUR OWN.

&&

LAT...LON 3003 9772 2988 9790 2986 9788 2968 9809
      2960 9829 2967 9838 2970 9838 2971 9834
      2973 9836 2975 9842 2972 9844 2976 9854
      2975 9865 3004 9829 3035 9817

$$

1 follow-up statement

496 
WGUS74 KEWX 091006
FFSEWX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
506 AM CDT SUN OCT 9 2011

TXC091-209-091200-
/O.CON.KEWX.FF.W.0006.000000T0000Z-111009T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
HAYS TX-COMAL TX-
506 AM CDT SUN OCT 9 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 700 AM CDT FOR COMAL
AND HAYS COUNTIES...

AT 456 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED TO 
DETECT A THUNDERSTORM COMPLEX PRODUCING HEAVY RAINS AND POSSIBLE 
FLASH FLOODING OVER COMAL AND HAYS COUNTIES.

RADAR ESTIMATES AND SURFACE REPORTS SUGGEST THAT AMOUNTS OF 2 TO 3 
INCHES HAVE OCCURRED ACROSS MUCH OF THE WARNED AREA. AN ADDITIONAL 
ONE-HALF TO ONE INCH OF RAIN COULD OCCUR BEFORE THE WARNING IS 
EXPECTED TO EXPIRE AT 7 AM. 

LOCATIONS IN THE WARNING AREA INCLUDE WOODCREEK...HENLY...DRIPPING
SPRINGS...DRIFTWOOD AND BUDA.

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 3003 9772 2988 9790 2986 9788 2968 9809
      2960 9829 2967 9838 2970 9838 2971 9834
      2973 9836 2975 9842 2972 9844 2976 9854
      2975 9865 3004 9829 3035 9817

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 8, 7:46 PM CDT	Areal Flood Advisory	EWX	Edwards, Val Verde	104 min
Oct 8, 9:29 PM CDT	Areal Flood Advisory	EWX	Edwards, Val Verde	2 hr
Oct 8, 11:15 PM CDT	Areal Flood Advisory	EWX	Bandera, Edwards, Kerr, Medina, Real, Uvalde	105 min
Oct 8, 11:28 PM CDT	Areal Flood Advisory	EWX	Maverick	2 hr
Oct 9, 12:49 AM CDT	Areal Flood Advisory	EWX	Bandera, Frio, Gillespie, Kendall, Kerr, Llano and 1 more	3 hr
Oct 9, 1:35 AM CDT	Areal Flood Advisory	EWX	Bandera, Bexar, Blanco, Burnet, Comal, Gillespie and 3 more	3 hr
Oct 9, 2:38 AM CDT	Flash Flood Warning	EWX	Bexar, Comal, Kendall	3 hr
Oct 9, 3:02 AM CDT	Flash Flood Watch	EWX	Bandera, Bastrop, Bexar, Blanco, Burnet, Caldwell and 14 more	12 hr
Oct 9, 3:21 AM CDT	Areal Flood Advisory	EWX	Bexar, Comal, Guadalupe, Hays, Kendall	2 hr
Oct 9, 3:28 AM CDT	Areal Flood Advisory	EWX	Blanco, Burnet, Comal, Hays, Kendall, Travis and 1 more	3 hr
Oct 9, 3:41 AM CDT	Severe Thunderstorm Warning	EWX	Bexar, Comal, Guadalupe	34 min
Oct 9, 4:25 AM CDT	Flash Flood Warning	EWX	Burnet, Llano	3 hr
Oct 9, 5:13 AM CDT	Flash Flood Warning	EWX	Burnet, Travis, Williamson	3 hr
Oct 9, 5:41 AM CDT	Areal Flood Advisory	EWX	Bexar	3 hr
Oct 9, 6:21 AM CDT	Areal Flood Advisory	EWX	Dimmit, Maverick, Zavala	3 hr
Oct 9, 8:04 AM CDT	Areal Flood Advisory	EWX	Travis, Williamson	116 min
Oct 9, 10:33 AM CDT	Areal Flood Advisory	EWX	Atascosa, Bexar, Comal, Guadalupe, Wilson	117 min

Nearby

Flash Flood Warnings in Texas, 2011 Every flash flood warning in 2011

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.