Alert archive / Texas / Flash Flood Warnings in 2017

Flash Flood Warning 20, NWS Austin/San Antonio, TX

July 14, 2017Val Verde County, Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Jul 14, 2017, 3:06 AM CDT for Val Verde 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
Jul 14, 2017, 3:06 AM CDT (08:06 UTC)
Expired
Jul 14, 2017, 6:00 AM CDT
In force
3 hr
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Flood severity
None

County Val Verde County, TX

The radar

The Laughlin AFB radar (KDFX), 111 km from the middle of the area, began a volume at 08:08 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 (KDLF), launched 00:00Z, 8.1 hours before the alert went out and 59 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 2017-07-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 303 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 2017-07-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 square meters per square second.193958Sfc1 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
303 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
1036 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

228 
WGUS54 KEWX 140806
FFWEWX
TXC465-141100-
/O.NEW.KEWX.FF.W.0020.170714T0806Z-170714T1100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Austin/San Antonio TX
306 AM CDT FRI JUL 14 2017

The National Weather Service in Austin San Antonio has issued a

* Flash Flood Warning for...
  Central Val Verde County in south central Texas...

* Until 600 AM CDT

* At 304 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to two and one half inches 
  of rain have already fallen. Flash flooding is expected to begin 
  shortly.

* Some locations that will experience flooding include...
  Shumla, Seminole Canyon State Park and U.S. Highway 90. 

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

&&

LAT...LON 2999 10123 2952 10119 2953 10126 2957 10124
      2963 10126 2962 10128 2958 10128 2958 10131
      2965 10130 2966 10134 2965 10136 2970 10137
      2975 10142 2977 10140 2975 10144 2995 10150

$$

PLATT
1 follow-up statement
024 
WGUS74 KEWX 140913
FFSEWX

Flash Flood Statement
National Weather Service Austin/San Antonio TX
413 AM CDT FRI JUL 14 2017

TXC465-141100-
/O.CON.KEWX.FF.W.0020.000000T0000Z-170714T1100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Val Verde TX-
413 AM CDT FRI JUL 14 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 600 AM CDT FOR
CENTRAL VAL VERDE COUNTY...

At 409 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Radar estimates up to 4 inches of rain 
have already fallen across central Val Verde county, including the 
Seminole Canyon State Park. Flash flooding is likely ongoing or 
will begin shortly.

Some locations that will experience flooding include...
Shumla, Seminole Canyon State Park and U.S. Highway 90. 

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

&&

LAT...LON 2999 10123 2952 10119 2953 10126 2957 10124
      2963 10126 2962 10128 2958 10128 2958 10131
      2965 10130 2966 10134 2965 10136 2970 10137
      2975 10142 2977 10140 2975 10144 2995 10150

$$

PLATT

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 14, 2:16 AM CDTAreal Flood AdvisoryEWXVal Verde3 hr
Jul 14, 5:05 AM CDTAreal Flood AdvisoryEWXVal Verde3 hr
Jul 14, 9:15 AM CDTAreal Flood AdvisoryEWXVal Verde2 hr

Nearby

Flash Flood Warnings in Texas, 2017Every flash flood warning in 2017

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.