Alert archive / Texas / Flash Flood Warnings in 2012

Flash Flood Warning 58, NWS Austin/San Antonio, TX

August 19, 2012Bexar County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Aug 19, 2012, 5:12 AM CDT for Bexar 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: Aug 19, 2012, 5:12 AM CDT (10:12 UTC)
Expired: Aug 19, 2012, 8:00 AM CDT
In force: 3 hr
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon
Flood severity: None

County Bexar County, TX

The radar

The Austin/San Antonio radar (KEWX), 54 km from the middle of the area, began a volume at 10:13 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
Aug 19, 5:30 AM CDT	FLASH FLOOD	3 Nw San Antonio, TX	THERE IS HIGH WATER ON THE LOWER LEVELS OF IH35 AFFECTING BOTH THE NORTHBOUND AND SOUTHBOUND LANES NEAR PRESA AVENUE.

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, 10.2 hours before the alert went out and 222 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: 1435 J/kg
Mixed-layer CIN: -108 J/kg
Mixed-layer LCL: 1442 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 35 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.7

Open this sounding in Storm Lab

The text

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

276 
WGUS54 KEWX 191012
FFWEWX
TXC029-191300-
/O.NEW.KEWX.FF.W.0058.120819T1012Z-120819T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
512 AM CDT SUN AUG 19 2012

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  BEXAR COUNTY...

* UNTIL 800 AM CDT.

* AT 505 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED  
  TO DETECT WATER LEVELS RISING AT LEON...SAN PEDRO... ZARZAMORA AND 
  APACHE CREEKS IN ADDITION TO SEVERAL STREET CLOSURES AROUND THE    
  CITY OF SAN ANTONIO DUE TO THE EARLIER HEAVY RAINS. THEREFORE...A  
  FLASH FLOOD WARNING IS BEING REISSUED FOR BEXAR COUNTY UNTIL 8 AM  
  CDT THIS MORNING.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...SAN
  ANTONIO...ALAMO HEIGHTS...CHINA GROVE...CROSS MOUNTAIN...
  ELMENDORF...HELOTES...HOLLYWOOD PARK...KIRBY...LACKLAND AFB...LEON
  SPRINGS...LEON VALLEY...LIVE OAK...OLMOS PARK...SEA WORLD...SHAVANO
  PARK...ST. HEDWIG...TERRELL HILLS...THE DOMINION AND WINDCREST.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 2929 9877 2970 9877 2970 9839 2954 9830
      2946 9815 2916 9840

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 9:18 PM CDT	Areal Flood Advisory	EWX	Guadalupe	2 hr
Aug 18, 10:01 PM CDT	Areal Flood Advisory	EWX	Williamson	119 min
Aug 18, 10:14 PM CDT	Areal Flood Advisory	EWX	Bexar	106 min
Aug 18, 10:28 PM CDT	Areal Flood Advisory	EWX	Travis	2 hr
Aug 18, 10:45 PM CDT	Flash Flood Warning	EWX	Travis, Williamson	105 min
Aug 18, 11:32 PM CDT	Flash Flood Warning	EWX	Bexar	118 min
Aug 18, 11:40 PM CDT	Areal Flood Advisory	EWX	Bastrop, Lee	110 min
Aug 18, 11:50 PM CDT	Areal Flood Advisory	EWX	Caldwell, Gonzales, Guadalupe	2 hr
Aug 19, 12:26 AM CDT	Areal Flood Advisory	EWX	Gillespie	2 hr
Aug 19, 12:50 AM CDT	Areal Flood Advisory	EWX	Bandera, Frio, Medina, Uvalde, Zavala	100 min
Aug 19, 1:16 AM CDT	Areal Flood Advisory	EWX	Fayette	104 min
Aug 19, 1:30 AM CDT	Areal Flood Advisory	EWX	Bexar, Kendall	2 hr
Aug 19, 2:00 AM CDT	Flash Flood Warning	EWX	Bexar	3 hr
Aug 19, 2:56 AM CDT	Flash Flood Warning	EWX	Medina	3 hr
Aug 19, 4:00 AM CDT	Areal Flood Advisory	EWX	Atascosa	2 hr
Aug 19, 4:54 AM CDT	Areal Flood Advisory	EWX	Wilson	2 hr
Aug 19, 5:40 AM CDT	Areal Flood Advisory	EWX	Zavala	110 min
Aug 19, 8:33 AM CDT	Areal Flood Advisory	EWX	Bexar	117 min
Aug 19, 10:25 AM CDT	River Flood Warning	EWX	Bexar	69 min
Aug 19, 11:05 AM CDT	River Flood Warning	EWX	Bexar, Wilson	22 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.