Alert archive / Texas / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 74, NWS Houston/Galveston, TX

July 31, 20184 counties in Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Jul 31, 2018, 12:38 AM CDT for 4 counties in Texas. It was in force for 26 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 31, 2018, 12:38 AM CDT (05:38 UTC)
Expired
Jul 31, 2018, 1:04 AM CDT
In force
26 min
Issued by
NWS Houston/Galveston, TX
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Grimes County, TX, Houston County, TX, Madison County, TX, Walker County, TX

The radar

The Ft Hood radar (KGRK), 159 km from the middle of the area, began a volume at 05:38 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

Lake Charles Mun, LA (KLCH), launched 00:00Z, 5.6 hours before the alert went out and 257 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, Lake Charles Mun, LA at 00:00Z on 2018-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2252 joules per kilogram.LCLLFCEL10008507005003002001001 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, Lake Charles Mun, LA at 00:00Z on 2018-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 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
2252 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
1151 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
16 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 severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Houston/Galveston, TX wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 30, 11:05 PM CDT, 1 hour 33 minutes earlier.

Area forecast discussion, Jul 30, 11:05 PM CDT, 1 hour 33 minutes before
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Hazardous weather outlook, Jul 30, 4:16 AM CDT, 20 hours 22 minutes before
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        Please try again in a few minutes.
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In the hours before

Special weather statement, Jul 30, 11:33 PM CDT, 1 hour 5 minutes before
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<body>
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    <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.
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      <p id="message2">
        Please try again in a few minutes.
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Special weather statement, Jul 31, 12:11 AM CDT, 27 minutes before
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</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.
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Special weather statement, Jul 31, 12:30 AM CDT, 8 minutes before
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  <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.
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      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

Everything else NWS Houston/Galveston, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 30, 11:33 PM CDTSpecial Weather StatementHGXBrazos42 min
Jul 31, 12:11 AM CDTSpecial Weather StatementHGXBrazos, Grimes, Madison, Walker49 min
Jul 31, 12:30 AM CDTSpecial Weather StatementHGXHouston, Trinity45 min
Jul 31, 1:14 AM CDTSpecial Weather StatementHGXHouston46 min
Jul 31, 6:15 AM CDTAreal Flood AdvisoryHGXHouston, Trinity2 hr
Jul 31, 6:44 AM CDTSpecial Weather StatementHGXAngelina31 min
Jul 31, 6:53 AM CDTSpecial Weather StatementHGXMadison52 min
Jul 31, 7:09 AM CDTSpecial Weather StatementHGXPolk, San Jacinto, Trinity, Walker51 min
Jul 31, 8:03 AM CDTSpecial Weather StatementHGXPolk, San Jacinto, Trinity, Walker42 min
Jul 31, 8:18 AM CDTAreal Flood AdvisoryHGXPolk, San Jacinto, Trinity3 hr
Jul 31, 8:50 AM CDTSpecial Weather StatementHGXPolk, San Jacinto, Walker55 min
Jul 31, 9:16 AM CDTFlash Flood WarningHGXPolk, San Jacinto2 hr
Jul 31, 9:45 AM CDTSpecial Weather StatementHGXHarris, Liberty, Montgomery, San Jacinto60 min
Jul 31, 9:55 AM CDTSpecial Marine WarningHGX35 min
Jul 31, 10:13 AM CDTAreal Flood AdvisoryHGXMontgomery, San Jacinto, Walker2 hr
Jul 31, 10:44 AM CDTSpecial Weather StatementHGXLiberty, Montgomery, San Jacinto61 min
Jul 31, 11:16 AM CDTSpecial Weather StatementHGXWaller44 min
Jul 31, 11:51 AM CDTSpecial Weather StatementHGXHarris54 min
Jul 31, 12:11 PM CDTSpecial Marine WarningHGX34 min
Jul 31, 12:14 PM CDTSpecial Weather StatementHGXHarris61 min
Jul 31, 12:21 PM CDTSevere Thunderstorm WarningHGXBrazoria, Galveston, Harris24 min
Jul 31, 12:35 PM CDTSpecial Weather StatementHGXBrazoria25 min
Jul 31, 12:40 PM CDTSpecial Marine WarningHGX35 min
Jul 31, 12:55 PM CDTAreal Flood AdvisoryHGXHarris65 min
Jul 31, 1:26 PM CDTSpecial Weather StatementHGXBrazoria49 min
Jul 31, 1:28 PM CDTFlash Flood WarningHGXGalveston52 min
Jul 31, 1:28 PM CDTSpecial Marine WarningHGX32 min

Nearby

Severe Thunderstorm Warnings in Texas, 2018Every severe thunderstorm warning 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.