Alert archive / Texas / Flash Flood Warnings in 2026

Flash Flood Warning 40, NWS Houston/Galveston, TX

September 2, 2026Polk County, Trinity County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Sep 2, 2026, 12:21 PM CDT for Polk County, Trinity County, Texas. It was in force for 7 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Sep 2, 2026, 12:21 PM CDT (17:21 UTC)
Expired
Sep 2, 2026, 7:15 PM CDT
In force
7 hr
Issued by
NWS Houston/Galveston, TX
Area
Storm-based polygon
Flood severity
None

Counties Polk County, TX, Trinity County, TX

The radar

The Houston radar (KHGX), 164 km from the middle of the area, began a volume at 17:24 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

Fort Worth, TX (KFWD), launched 12:00Z, 5.4 hours before the alert went out and 303 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, Fort Worth, TX at 12:00Z on 2026-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 104 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, Fort Worth, TX at 12:00Z on 2026-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -12 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
104 J/kg
Mixed-layer CIN
-160 J/kg
Mixed-layer LCL
1469 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-12 m²/s²
0-3 km storm-relative helicity
38 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 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 flash flood warning went out at Sep 2, 10:26 AM CDT, 1 hour 55 minutes earlier.

Area forecast discussion, Sep 2, 10:26 AM CDT, 1 hour 55 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>

In the hours before

Local storm report, Sep 2, 6:36 AM CDT, 5 hours 45 minutes before
Preliminary Local Storm Report
National Weather Service Houston/Galveston TX
636 AM CDT Wed Sep 2 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0608 AM     Flash Flood      12 SE Seven Oaks        30.72N 94.72W
09/02/2026                   Polk               TX   Emergency Mngr

            6-8 inches of water across Johnson Branch
            Road.

&&

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 1, 10:24 PM CDTAreal Flood AdvisoryHGXLiberty, Polk, San Jacinto3 hr
Sep 1, 11:09 PM CDTFlash Flood WarningHGXPolk7 hr
Sep 2, 1:32 AM CDTFlash Flood WarningHGXPolk5 hr
Sep 2, 2:06 AM CDTAreal Flood AdvisoryHGXChambers, Liberty99 min
Sep 2, 2:22 AM CDTFlash Flood WarningHGXChambers, Liberty4 hr
Sep 2, 2:26 AM CDTSpecial Weather StatementHGXHardin34 min
Sep 2, 3:44 AM CDTFlash Flood WarningHGXLiberty3 hr
Sep 2, 5:51 AM CDTFlash Flood WarningHGXLiberty, Montgomery, San Jacinto4 hr
Sep 2, 6:04 AM CDTFlash Flood Warning Considerable damage threatHGXPolk, San Jacinto3 hr
Sep 2, 6:53 AM CDTFlash Flood Warning Considerable damage threatHGXLiberty3 hr
Sep 2, 6:53 AM CDTSpecial Marine WarningHGX52 min
Sep 2, 7:16 AM CDTAreal Flood AdvisoryHGXPolk, San Jacinto, Trinity, Walker119 min
Sep 2, 7:25 AM CDTAreal Flood AdvisoryHGXPolk, Trinity5 hr
Sep 2, 9:23 AM CDTFlash Flood Warning Considerable damage threatHGXLiberty, Polk4 hr
Sep 2, 10:35 AM CDTRiver Flood WarningHGXPolk, San Jacinto29 hr
Sep 2, 10:56 AM CDTRiver Flood WarningHGXHardin, Liberty, Polk70 hr
Sep 2, 1:06 PM CDTAreal Flood WarningHGXLiberty3 hr
Sep 2, 2:35 PM CDTAreal Flood AdvisoryHGXPolk, San Jacinto, Walker3 hr
Sep 2, 3:03 PM CDTFlash Flood Warning Considerable damage threatHGXPolk4 hr
Sep 2, 4:41 PM CDTSevere Thunderstorm WarningHGXPolk, San Jacinto49 min
Sep 2, 4:42 PM CDTAreal Flood AdvisoryHGXMontgomery, San Jacinto, Walker36 min
Sep 2, 4:49 PM CDTFlash Flood Warning Considerable damage threatHGXPolk, San Jacinto6 hr
Sep 2, 5:18 PM CDTFlash Flood WarningHGXMontgomery, Polk, San Jacinto, Walker4 hr
Sep 2, 5:30 PM CDTSevere Thunderstorm WarningHGXLiberty, Polk, San Jacinto30 min
Sep 2, 6:00 PM CDTSpecial Weather StatementHGXPolk30 min
Sep 2, 6:15 PM CDTFlash Flood WarningHGXLiberty, San Jacinto3 hr
Sep 2, 6:40 PM CDTSpecial Weather StatementHGXPolk35 min
Sep 2, 6:47 PM CDTTornado WarningHGXMontgomery28 min
Sep 2, 6:59 PM CDTAreal Flood AdvisoryHGXMontgomery2 hr

Nearby

Flash Flood Warnings in Texas, 2026Every flash flood warning in 2026

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.