Alert archive / Texas / Flash Flood Watches in 2018

Flash Flood Watch 10, NWS Austin/San Antonio, TX

October 23, 201818 counties in Texas

NWS Austin/San Antonio, TX issued this flash flood watch at Oct 23, 2018, 3:09 PM CDT for 18 counties in Texas. It took effect at Oct 24, 2018, 1:00 AM CDT. It was in force for 18 hr.

The area

The counties it named.

The facts

Issued
Oct 23, 2018, 3:09 PM CDT (20:09 UTC)
In effect from
Oct 24, 2018, 1:00 AM CDT
Expired
Oct 24, 2018, 7:00 PM CDT
In force
18 hr
Issued by
NWS Austin/San Antonio, TX
Flood severity
None

Counties Bandera County, TX, Bexar County, TX, Blanco County, TX, Burnet County, TX, Comal County, TX, Edwards County, TX, Gillespie County, TX, Hays County, TX, Kendall County, TX, Kerr County, TX, Kinney County, TX, Llano County, TX, Medina County, TX, Real County, TX, Travis County, TX, Uvalde County, TX, Val Verde County, TX, Williamson County, TX

The radar

The Austin/San Antonio radar (KEWX), 101 km from the middle of the area, began a volume at 20:11 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 12:00Z, 8.2 hours before the alert went out and 300 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, Corpus Christi, TX at 12:00Z on 2018-10-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Corpus Christi, TX at 12:00Z on 2018-10-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 365 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
786 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
365 m²/s²
0-3 km storm-relative helicity
386 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Austin/San Antonio, TX wrote its last area forecast discussion before this flash flood watch went out at Oct 23, 12:34 PM CDT, 2 hours 35 minutes earlier.

Area forecast discussion, Oct 23, 12:34 PM CDT, 2 hours 35 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Hazardous weather outlook, Oct 23, 1:58 PM CDT, 1 hour 11 minutes before
Hazardous Weather Outlook
National Weather Service Austin/San Antonio TX
158 PM CDT Tue Oct 23 2018

TXZ171>173-183>194-202>209-217>225-228-241200-
Llano-Burnet-Williamson-Val Verde-Edwards-Real-Kerr-Bandera-
Gillespie-Kendall-Blanco-Hays-Travis-Bastrop-Lee-Kinney-Uvalde-
Medina-Bexar-Comal-Guadalupe-Caldwell-Fayette-Maverick-Zavala-
Frio-Atascosa-Wilson-Karnes-Gonzales-De Witt-Lavaca-Dimmit-
158 PM CDT Tue Oct 23 2018

This Hazardous Weather Outlook is for South-Central Texas..

.DAY ONE...This Afternoon And Tonight.

Expect light rain to re-develop from southwest to northeast
across the area tonight. Rainfall amounts of up to an inch are
possible, mainly across the Rio Grande Plains, Edwards Plateau,
and Hill Country. This rain on saturated soils could lead to
renewed river flooding and some minor flash flooding. The
Colorado, Llano, Nueces, Frio, and Rio Grande river basins are the
areas most at risk from additional rainfall.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

An upper level trough and the remnants of Pacific Hurricane Willa
will bring periods of moderate rainfall on Wednesday. Rainfall
amounts of 1 to 3 inches are possible, with a few spots getting
up to 4 inches. Look for renewed river flooding and some minor
flash flooding. The Colorado, Llano, Nueces, Frio, and Rio Grande
river basins are the areas most at risk from additional rainfall.

The rain will end Thursday, followed by dry and mild weather into
the middle of next week. However, rivers and lakes will remain at
elevated levels from recent rains.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

Nearby

Flash Flood Watches in Texas, 2018Every flash flood watch in 2018

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.