Alert archive / Texas / Flash Flood Warnings in 2021

Flash Flood Warning 31, NWS Houston/Galveston, TX

September 13, 2021Brazoria County, Jackson County, Matagorda County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Sep 13, 2021, 7:32 PM CDT for Brazoria County, Jackson County, Matagorda 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
Sep 13, 2021, 7:32 PM CDT (00:32 UTC)
Expired
Sep 13, 2021, 10:30 PM CDT
In force
3 hr
Issued by
NWS Houston/Galveston, TX
Area
Storm-based polygon
Flood severity
None

Counties Brazoria County, TX, Jackson County, TX, Matagorda County, TX

The radar

The Houston radar (KHGX), 128 km from the middle of the area, began a volume at 00:35 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 00:00Z, 0.5 hours before the alert went out and 166 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 00:00Z on 2021-09-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 36 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, Corpus Christi, TX at 00:00Z on 2021-09-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -68 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
36 J/kg
Mixed-layer CIN
-242 J/kg
Mixed-layer LCL
656 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
-68 m²/s²
0-3 km storm-relative helicity
-42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

868 
WGUS54 KHGX 140032
FFWHGX
TXC039-239-321-140330-
/O.NEW.KHGX.FF.W.0031.210914T0032Z-210914T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Houston/Galveston TX
732 PM CDT Mon Sep 13 2021

The National Weather Service in League City has issued a

* Flash Flood Warning for...
  Eastern Jackson County in south central Texas...
  Southwestern Brazoria County in southeastern Texas...
  Matagorda County in southeastern Texas...

* Until 1030 PM CDT.

* At 732 PM CDT, Local law enforcement reported heavy rain across 
  the warned area. FM 2031 remains closed due to high water. Between 
  1 and 3 inches of rain have fallen. Additional rainfall amounts of 
  2 to 3 inches are possible in the warned area. Flash flooding is 
  ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Law enforcement reported.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Matagorda, southern Lake Jackson, southern Bay City, Freeport, 
  Clute, Palacios, Sweeny, Surfside Beach, South Texas Nuclear 
  Plant, Brazoria, Jones Creek, Sargent, Wild Peach Village and 
  Wadsworth.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 2874 9636 2912 9563 2893 9523 2845 9620
      2858 9628 2861 9627 2860 9629

FLASH FLOOD...OBSERVED

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 13, 9:46 PM CDTFlash Flood WarningHGXBrazoria, Galveston, Matagorda4 hr
Sep 13, 10:06 PM CDTHurricane WarningHGXBrazoria, Jackson, Matagorda6 hr
Sep 13, 10:31 PM CDTFlash Flood WarningHGXMatagorda3 hr
Sep 14, 1:43 AM CDTFlash Flood WarningHGXBrazoria, Galveston, Harris, Matagorda4 hr
Sep 14, 3:33 AM CDTFlash Flood WarningHGXBrazoria, Chambers, Galveston, Harris4 hr
Sep 14, 3:57 AM CDTSmall Craft AdvisoryHGX18 hr
Sep 14, 4:04 AM CDTCoastal Flood AdvisoryHGXBrazoria, Chambers, Galveston, Harris, Matagorda14 hr
Sep 14, 4:42 AM CDTRiver Flood WarningHGXGalveston, Harris28 hr
Sep 14, 5:29 AM CDTRiver Flood WarningHGXGalveston, Harris21 days
Sep 14, 5:31 AM CDTRiver Flood WarningHGXGalveston, Harris21 days
Sep 14, 5:45 AM CDTFlash Flood WarningHGXBrazoria, Chambers, Galveston, Harris3 hr
Sep 14, 8:11 AM CDTAreal Flood WarningHGXBrazoria, Galveston, Harris3 hr

Nearby

Flash Flood Warnings in Texas, 2021Every flash flood warning 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.