Alert archive / Texas / Flash Flood Warnings in 2012

Flash Flood Warning 15, NWS Brownsville, TX

September 29, 2012Zapata County, Texas

NWS Brownsville, TX issued this flash flood warning at Sep 29, 2012, 3:42 AM CDT for Zapata County, Texas. It was in force for 48 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Sep 29, 2012, 3:42 AM CDT (08:42 UTC)
Expired: Sep 29, 2012, 4:30 AM CDT
In force: 48 min
Issued by: NWS Brownsville, TX
Area: Storm-based polygon
Flood severity: None

County Zapata County, TX

The radar

The Corpus Christi radar (KCRP), 197 km from the middle of the area, began a volume at 08:44 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

Corpus Christi, TX (KCRP), launched 00:00Z, 8.7 hours before the alert went out and 212 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: 1843 J/kg
Mixed-layer CIN: -8 J/kg
Mixed-layer LCL: 639 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 85 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 3.1

Open this sounding in Storm Lab

The text

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

373 
WGUS54 KBRO 290842
FFWBRO
TXC505-290930-
/O.NEW.KBRO.FF.W.0015.120929T0842Z-120929T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BROWNSVILLE TX
342 AM CDT SAT SEP 29 2012

THE NATIONAL WEATHER SERVICE IN BROWNSVILLE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHWESTERN ZAPATA COUNTY IN DEEP SOUTH TEXAS...

* UNTIL 430 AM CDT

* AT 340 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS INDICATED
  TORRENTIAL RAIN OF THREE TO FIVE INCHES PER HOUR FROM A SLOW MOVING
  THUNDERSTORM WITH VERY HEAVY RAINFALL. 

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS TO RISE.

THIS IS A LIFE THREATENING FLOOD! MOST FLOOD DEATHS OCCUR IN
AUTOMOBILES. STAY HOME. IF TRAVELING...DO NOT CROSS FLOODED ROADWAYS
OR STREAMS. WHEN NEARING A FLOOD AREA...TURN AROUND AND DRIVE TO
HIGHER TERRAIN.

DON'T BECOME A STATISTIC. TURN AROUND...DON'T DROWN!

&&

LAT...LON 2707 9945 2708 9944 2715 9945 2716 9943
      2719 9943 2722 9945 2725 9945 2727 9946
      2732 9937 2728 9933 2727 9915 2706 9916
      2706 9945

$$

63

1 follow-up statement

011 
WGUS74 KBRO 290917
FFSBRO

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE BROWNSVILLE TX
417 AM CDT SAT SEP 29 2012

TXC505-290930-
/O.CON.KBRO.FF.W.0015.000000T0000Z-120929T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
ZAPATA TX-
417 AM CDT SAT SEP 29 2012

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR NORTHWESTERN ZAPATA
COUNTY UNTIL 430 AM CDT...

  LOCATIONS AFFECTED INCLUDE...

AT 416 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS INDICATED
TORRENTIAL RAIN OF THREE TO FIVE INCHES PER HOUR FROM SLOW
MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL. 

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS TO RISE.

THIS IS A LIFE THREATENING FLOOD! MOST FLOOD DEATHS OCCUR IN
AUTOMOBILES. STAY HOME. IF TRAVELING...DO NOT CROSS FLOODED ROADWAYS
OR STREAMS. WHEN NEARING A FLOOD AREA...TURN AROUND AND DRIVE TO
HIGHER TERRAIN.

&&

LAT...LON 2707 9945 2708 9944 2715 9945 2716 9943
      2719 9943 2722 9945 2725 9945 2727 9946
      2732 9937 2728 9933 2727 9915 2706 9916
      2706 9945

$$

63

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 29, 1:49 AM CDT	Areal Flood Advisory	BRO	Zapata	56 min
Sep 29, 2:44 AM CDT	Areal Flood Advisory	BRO	Zapata	61 min
Sep 29, 4:06 AM CDT	Small Craft Advisory	BRO		39 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.