Alert archive / Texas / Flash Flood Warnings in 2021

Flash Flood Warning 37, NWS Austin/San Antonio, TX

July 6, 2021Bexar County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Jul 6, 2021, 6:39 AM CDT for Bexar County, Texas. It was in force for 5 hr. 4 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 6, 2021, 6:39 AM CDT (11:39 UTC)
Expired
Jul 6, 2021, 12:00 PM CDT
In force
5 hr
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Bexar County, TX

The radar

The Austin/San Antonio radar (KEWX), 63 km from the middle of the area, began a volume at 11:40 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 6, 6:57 AM CDTFLASH FLOOD3 S Helotes, TXLOW WATER CROSSING ON LESLIE RD REPORTED CLOSED VIA BEXARFLOOD.ORG.
Jul 6, 7:09 AM CDTFLASH FLOOD1 Ese Balcones Heights, TXMPING REPORT OF STREET FLOODING. REPORTS IS NEAR I-10 AND VANCE JACKSON RD.
Jul 6, 7:50 AM CDTFLASH FLOOD1 Wsw Cross Mountain, TXBEXAR COUNTY RAINFALL WEBSITE SHOWS WATER OVER THE ROADS AT TOUTANT BEAUREGARD NEAR WILD SAGE AND CIELO VISTA DRIVE SOUTH OF VISTA MOUNTAIN. IMPRESSIVE RAINFALL RATES OF OVER 2.5 INCHES IN AN HOUR STILL ONGOING.
Jul 6, 8:37 AM CDTFLASH FLOOD1 Ene Cross Mountain, TXWATER CROSSING FLOODED AT CIELO VISTA DRIVE SOUTH OF VISTA MONTAN DRIVE.

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

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 11.7 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-pSkew-T log-p diagram, Del Rio, TX at 00:00Z on 2021-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 322 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Del Rio, TX at 00:00Z on 2021-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -92 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
322 J/kg
Mixed-layer CIN
-70 J/kg
Mixed-layer LCL
665 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-92 m²/s²
0-3 km storm-relative helicity
-68 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

799 
WGUS54 KEWX 061139
FFWEWX
TXC029-061430-
/O.NEW.KEWX.FF.W.0037.210706T1139Z-210706T1430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Austin/San Antonio TX
639 AM CDT Tue Jul 6 2021

The National Weather Service in Austin/San Antonio has issued a

* Flash Flood Warning for...
  Northwestern Bexar County in south central Texas...

* Until 930 AM CDT.

* At 639 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  San Antonio, Leon Valley, Helotes, Fair Oaks Ranch, Shavano Park, 
  Cross Mountain, Sea World, Government Canyon State Natural Area, 
  Lackland AFB, The Dominion, Leon Springs, Castle Hills, Balcones 
  Heights, Grey Forest, Fiesta Texas, San Geronimo, Macdona and 
  Scenic Oaks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 2972 9878 2972 9876 2972 9874 2972 9873
      2973 9873 2973 9872 2974 9870 2974 9866
      2975 9866 2975 9865 2974 9864 2974 9862
      2974 9861 2974 9860 2975 9860 2975 9859
      2927 9847 2934 9880 2969 9881

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...2 INCHES IN 1 HOUR

$$

RUNYEN
2 follow-up statements
153 
WGUS54 KEWX 061319
FFWEWX
TXC029-061530-
/O.EXT.KEWX.FF.W.0037.000000T0000Z-210706T1530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Austin/San Antonio TX
819 AM CDT Tue Jul 6 2021

The National Weather Service in Austin/San Antonio has extended the

* Flash Flood Warning for...
  Northwestern Bexar County in south central Texas...

* Until 1030 AM CDT.

* At 819 AM CDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  2 and 5 inches of rain have fallen. The expected rainfall rate is 
  1 to 2 inches in 1 hour. Additional rainfall amounts of 1 to 2 
  inches are possible in the warned area. Flash flooding is ongoing.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar and automated gauges.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  San Antonio, Leon Valley, Helotes, Fair Oaks Ranch, Shavano Park, 
  Cross Mountain, Sea World, Government Canyon State Natural Area, 
  Lackland AFB, The Dominion, Leon Springs, Castle Hills, Balcones 
  Heights, Grey Forest, Fiesta Texas, San Geronimo, Macdona and 
  Scenic Oaks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 2972 9878 2972 9876 2972 9874 2972 9873
      2973 9873 2973 9872 2974 9870 2974 9866
      2975 9866 2975 9865 2974 9864 2974 9862
      2974 9861 2974 9860 2975 9860 2975 9859
      2927 9847 2934 9880 2969 9881

FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

KCW
289 
WGUS54 KEWX 061448
FFWEWX
TXC029-061700-
/O.EXT.KEWX.FF.W.0037.000000T0000Z-210706T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Austin/San Antonio TX
948 AM CDT Tue Jul 6 2021

The National Weather Service in Austin/San Antonio has extended the

* Flash Flood Warning for...
  Northwestern Bexar County in south central Texas...

* Until noon CDT.

* At 948 AM CDT, Doppler radar and automated rain gauges indicated 
  heavy rain falling across the warned area. Between 2 and 6 inches 
  of rain have fallen. The expected rainfall rate is 0.25 to 1 inch 
  in 1 hour. Additional rainfall amounts up to 1 inch are possible 
  in the warned area. Flash flooding is ongoing.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  San Antonio, Leon Valley, Helotes, Fair Oaks Ranch, Shavano Park, 
  Cross Mountain, Sea World, Government Canyon State Natural Area, 
  Lackland AFB, The Dominion, Leon Springs, Castle Hills, Balcones 
  Heights, Grey Forest, Fiesta Texas, San Geronimo, Macdona and 
  Scenic Oaks.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 2972 9878 2972 9876 2972 9874 2972 9873
      2973 9873 2973 9872 2974 9870 2974 9866
      2975 9866 2975 9865 2974 9864 2974 9862
      2974 9861 2974 9860 2975 9860 2975 9859
      2927 9847 2934 9880 2969 9881

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...0.25-1 INCH IN 1 HOUR

$$

KCW

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 5, 7:01 PM CDTAreal Flood AdvisoryEWXBandera, Kerr3 hr
Jul 6, 4:43 AM CDTAreal Flood AdvisoryEWXBlanco, Comal, Kendall3 hr
Jul 6, 6:06 AM CDTAreal Flood AdvisoryEWXBexar, Medina3 hr
Jul 6, 6:47 AM CDTAreal Flood AdvisoryEWXAtascosa3 hr
Jul 6, 10:15 AM CDTRiver Flood WarningEWXBexar22 hr
Jul 6, 10:34 AM CDTAreal Flood AdvisoryEWXGillespie3 hr
Jul 6, 2:47 PM CDTRiver Flood WarningEWXBexar20 hr
Jul 6, 4:56 PM CDTRiver Flood WarningEWXKarnes, Wilson62 hr
Jul 6, 4:57 PM CDTRiver Flood WarningEWXBexar, Wilson42 hr

Nearby

Flash Flood Warnings in Texas, 2021Every flash flood warning in 2021

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.