Alert archive / Texas / Special Weather Statements in 2021

Special Weather Statement, NWS Houston/Galveston, TX

July 12, 2021San Jacinto County, Texas

NWS Houston/Galveston, TX issued this special weather statement at Jul 12, 2021, 9:36 AM CDT for San Jacinto County, Texas. It was in force for 39 min. 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 12, 2021, 9:36 AM CDT (14:36 UTC)
Expired: Jul 12, 2021, 10:15 AM CDT
In force: 39 min
Issued by: NWS Houston/Galveston, TX

County San Jacinto County, TX

The radar

The Houston radar (KHGX), 145 km from the middle of the area, began a volume at 14:38 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 12:00Z, 2.6 hours before the alert went out and 194 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2909 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 749 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 86 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement 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 special weather statement went out at Jul 12, 6:22 AM CDT, 3 hours 14 minutes earlier.

Area forecast discussion, Jul 12, 6:22 AM CDT, 3 hours 14 minutes before

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<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.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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In the hours before

Special weather statement, Jul 12, 9:08 AM CDT, 28 minutes before

Special Weather Statement
National Weather Service Houston/Galveston TX
908 AM CDT Mon Jul 12 2021

TXZ164-177>179-121445-
San Jacinto TX-Walker TX-Polk TX-Trinity TX-
908 AM CDT Mon Jul 12 2021

...Strong Thunderstorms Moving From Walker County into San Jacinto
County...

At 907 AM CDT, Doppler radar was tracking a strong thunderstorm 7
miles west of Point Blank, or 13 miles east of Huntsville, moving
northeast at 25 mph.

Winds to about 40 mph will be possible with the strongest part of
this storm.

Locations impacted include...
Onalaska, Point Blank and Oakhurst.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3065 9549 3076 9542 3092 9516 3069 9506
TIME...MOT...LOC 1407Z 244DEG 24KT 3071 9533

Special weather statement, Jul 12, 9:36 AM CDT, 0 minutes before

Special Weather Statement
National Weather Service Houston/Galveston TX
936 AM CDT Mon Jul 12 2021

TXZ164-177>179-199-121515-
San Jacinto TX-Walker TX-Polk TX-Montgomery TX-Trinity TX-
936 AM CDT Mon Jul 12 2021

...Strong Thunderstorms Capable of Producing Heavy Rain and Gusty
Winds...

At 935 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Point Blank to 10 miles west of Coldspring
to near Panorama Village. Movement was northeast at 25 mph.

Winds in excess of 30 mph will be possible with these storms.

Locations impacted include...
Northwestern Conroe, Willis, Livingston, Shepherd, Panorama Village,
Onalaska, Corrigan, Coldspring, Point Blank, Lake Livingston State
Park, West Livingston, Oakhurst and Evergreen.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3112 9479 3073 9492 3050 9501 3033 9554
      3049 9543 3081 9530 3113 9481
TIME...MOT...LOC 1435Z 238DEG 20KT 3082 9521 3054 9530 3038 9546

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 11, 7:21 PM CDT	Special Weather Statement	HGX	Houston	39 min
Jul 11, 7:39 PM CDT	Special Weather Statement	HGX	Houston	51 min
Jul 11, 7:58 PM CDT	Special Weather Statement	HGX	Houston	47 min
Jul 12, 8:29 AM CDT	Areal Flood Advisory	HGX	Brazos, Madison	3 hr
Jul 12, 9:03 AM CDT	Areal Flood Advisory	HGX	Walker	117 min
Jul 12, 9:08 AM CDT	Special Weather Statement	HGX	San Jacinto	37 min
Jul 12, 10:12 AM CDT	Special Weather Statement	HGX	Liberty, Polk, San Jacinto	48 min
Jul 12, 11:29 AM CDT	Areal Flood Advisory	HGX	Brazos, Madison	3 hr
Jul 12, 11:33 AM CDT	Areal Flood Advisory	HGX	Houston	3 hr
Jul 12, 12:01 PM CDT	Special Weather Statement	HGX	Brazos	59 min
Jul 12, 12:43 PM CDT	Severe Thunderstorm Warning	HGX	Brazos, Burleson	18 min
Jul 12, 1:10 PM CDT	Areal Flood Advisory	HGX	Brazos, Grimes	110 min
Jul 12, 1:21 PM CDT	Tornado Warning	HGX	Montgomery, Walker	12 min
Jul 12, 2:34 PM CDT	Special Weather Statement	HGX	Montgomery, San Jacinto, Waller	41 min
Jul 12, 3:06 PM CDT	Special Weather Statement	HGX	Harris	39 min
Jul 12, 3:43 PM CDT	Special Weather Statement	HGX	Fort Bend, Harris	47 min
Jul 12, 4:31 PM CDT	Special Weather Statement	HGX	Chambers, Fort Bend	59 min

Nearby

Special Weather Statements in Texas, 2021 Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.