Alert archive / Texas / Flash Flood Warnings in 2019

Flash Flood Warning 39, NWS Austin/San Antonio, TX

September 19, 2019Bexar County, Medina County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Sep 19, 2019, 10:03 PM CDT for Bexar County, Medina County, Texas. It was in force for 3 hr. 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 19, 2019, 10:03 PM CDT (03:03 UTC)
Expired
Sep 20, 2019, 1:00 AM CDT
In force
3 hr
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Flood severity
None

Counties Bexar County, TX, Medina County, TX

The radar

The Austin/San Antonio radar (KEWX), 65 km from the middle of the area, began a volume at 03:04 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

Del Rio, TX (KDRT), launched 00:00Z, 3.1 hours before the alert went out and 210 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 2019-09-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 290 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 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 2019-09-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -23 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
290 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
2606 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-23 m²/s²
0-3 km storm-relative helicity
29 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

447 
WGUS54 KEWX 200303
FFWEWX
TXC029-325-200600-
/O.NEW.KEWX.FF.W.0039.190920T0303Z-190920T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Austin/San Antonio TX
1003 PM CDT Thu Sep 19 2019

The National Weather Service in Austin San Antonio has issued a

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

* Until 100 AM CDT.

* At 1001 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain from Medina Lake to Helotes to Leon Springs. The 
  heaviest rains are along State Highway 16. Up to two inches of 
  rain have already fallen. Flash flooding is expected to begin 
  shortly.

* Some locations that will experience flooding include...
  San Antonio, Helotes, Shavano Park, Cross Mountain, Government
  Canyon State Natural Area, Leon Springs, The Dominion, Grey Forest,
  Fiesta Texas, Scenic Oaks and San Geronimo.

Additional rainfall amounts of 1 to 3 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 2971 9864 2961 9854 2953 9866 2957 9892
      2972 9877

$$

CP
2 follow-up statements
793 
WGUS74 KEWX 200403
FFSEWX

Flash Flood Statement
National Weather Service Austin/San Antonio TX
1103 PM CDT Thu Sep 19 2019

TXC029-325-200600-
/O.CON.KEWX.FF.W.0039.000000T0000Z-190920T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Medina TX-Bexar TX-
1103 PM CDT Thu Sep 19 2019

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 AM CDT FOR
NORTHEASTERN MEDINA AND NORTHWESTERN BEXAR COUNTIES...

At 1059 PM CDT, Doppler radar indicated light rain across the warned 
area. Radar estimates and rain gauges indicated up to almost four 
inches of rain have already fallen in an area west of Interstate 10, 
along and northwest of Loop 1604 to Medina Lake. A rain gauge at 
Haby Lane just east of State Highway 16 reported 3.58 inches. Flash 
flooding will continue. 

Some locations that will experience flooding include...
San Antonio, Helotes, Shavano Park, Cross Mountain, Government Canyon
State Natural Area, Leon Springs, The Dominion, Grey Forest, Fiesta
Texas, Scenic Oaks and San Geronimo.

Additional rainfall amounts of less than one tench inch are possible 
in the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 2971 9864 2961 9854 2953 9866 2957 9892
      2972 9877

$$

CP
055 
WGUS74 KEWX 200608
FFSEWX

Flash Flood Statement
National Weather Service Austin/San Antonio TX
108 AM CDT Fri Sep 20 2019

TXC029-325-200617-
/O.EXP.KEWX.FF.W.0039.000000T0000Z-190920T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Medina TX-Bexar TX-
108 AM CDT Fri Sep 20 2019

...THE FLASH FLOOD WARNING FOR NORTHEASTERN MEDINA AND NORTHWESTERN
BEXAR COUNTIES HAS EXPIRED...

The heavy rain has ended. Flood waters have receded. Flooding is no
longer expected to pose a threat. Please continue to heed any
remaining road closures.

LAT...LON 2971 9864 2961 9854 2953 9866 2957 9892
      2972 9877

$$

CP

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 19, 7:23 PM CDTSpecial Weather StatementEWXGonzales52 min
Sep 19, 7:30 PM CDTSevere Thunderstorm WarningEWXGonzales, Lavaca26 min
Sep 19, 7:44 PM CDTAreal Flood AdvisoryEWXCaldwell, Fayette, Gonzales, Lavaca3 hr
Sep 19, 7:50 PM CDTSevere Thunderstorm WarningEWXGonzales, Guadalupe55 min
Sep 19, 8:14 PM CDTSpecial Weather StatementEWXGuadalupe61 min
Sep 19, 8:37 PM CDTSevere Thunderstorm WarningEWXBexar, Comal, Guadalupe, Wilson53 min
Sep 19, 8:42 PM CDTAreal Flood AdvisoryEWXBexar, Guadalupe3 hr
Sep 19, 8:49 PM CDTSpecial Weather StatementEWXBexar56 min
Sep 19, 9:01 PM CDTSevere Thunderstorm WarningEWXBexar59 min
Sep 19, 9:14 PM CDTAreal Flood AdvisoryEWXBexar3 hr
Sep 19, 9:26 PM CDTFlash Flood WarningEWXBexar, Guadalupe3 hr
Sep 19, 9:35 PM CDTSevere Thunderstorm WarningEWXBandera, Bexar, Medina55 min
Sep 19, 10:16 PM CDTSevere Thunderstorm WarningEWXBandera, Medina39 min
Sep 19, 10:48 PM CDTSpecial Weather StatementEWXReal42 min

Nearby

Flash Flood Warnings in Texas, 2019Every flash flood warning in 2019

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.