Alert archive / Texas / Flash Flood Warnings in 2021

Flash Flood Warning 5, NWS Houston/Galveston, TX

May 16, 20215 counties in Texas

NWS Houston/Galveston, TX issued this flash flood warning at May 16, 2021, 11:26 AM CDT for 5 counties in Texas. It was in force for 4 hr. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
May 16, 2021, 11:26 AM CDT (16:26 UTC)
Expired
May 16, 2021, 3:00 PM CDT
In force
4 hr
Issued by
NWS Houston/Galveston, TX
Area
Storm-based polygon
Flood severity
None

Counties Brazoria County, TX, Colorado County, TX, Jackson County, TX, Matagorda County, TX, Wharton County, TX

The radar

The Austin/San Antonio radar (KEWX), 147 km from the middle of the area, began a volume at 16:27 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.

What was reported inside it

TimeReportWhereRemark
May 16, 12:20 PM CDTFLASH FLOOD8 Ne Ganado, TXLOCAL EMC REPORTED WATER OVER ROADS NEAR LOUISE.
May 16, 1:36 PM CDTFLASH FLOOD6 Ese Ganado, TXFM 1157 CLOSED DUE TO FLOODWATERS OVER ROAD BETWEEN CR-208 AND CR-215.
May 16, 1:36 PM CDTFLASH FLOOD9 Wsw Markham, TXFM 111 CLOSED DUE TO FLOODWATERS FLOWING OVER ROAD BETWEEN TX-172 AND TX-71 IN MIDFIELD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 12:00Z, 4.4 hours before the alert went out and 169 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 2021-05-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2495 joules per kilogram.LCLEL10008507005003002001001 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 2021-05-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 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
2495 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
504 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
230 m²/s²
Significant tornado parameter
2.4
Supercell composite
12.7

Open this sounding in Storm Lab

The text

As transmitted.

934 
WGUS54 KHGX 161626
FFWHGX
TXC039-089-239-321-481-161830-
/O.NEW.KHGX.FF.W.0005.210516T1626Z-210516T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Houston/Galveston TX
1126 AM CDT Sun May 16 2021

The National Weather Service in League City has issued a

* Flash Flood Warning for...
  Northern Jackson County in south central Texas...
  Southwestern Brazoria County in southeastern Texas...
  Southeastern Colorado County in southeastern Texas...
  Northern Matagorda County in southeastern Texas...
  Southern Wharton County in southeastern Texas...

* Until 130 PM CDT.

* At 1126 AM CDT, Doppler radar indicated thunderstorms continuing 
  to produce heavy rain across the warned area. Between 3 and 5 
  inches of rain have fallen across the area with localized rainfall 
  totals of up to 8 to 10 inches. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Bay City, El Campo, Edna, Sweeny, Ganado, Blessing, Markham, Van 
  Vleck, Danevang, Midfield, Louise, Wadsworth, Cordele and Morales.

Additional rainfall amounts of up to 2 to 3 inches per hour are 
possible in the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 2929 9663 2929 9662 2931 9659 2931 9658
      2903 9560 2875 9587 2902 9684 2903 9684
      2903 9685 2903 9686 2904 9689 2906 9694
      2910 9689 2910 9688 2911 9688 2914 9683
      2920 9674 2925 9668

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...2-3 INCHES IN 1 HOUR 

$$

Cady
1 follow-up statement
407 
WGUS54 KHGX 161803
FFWHGX
TXC039-089-239-321-481-162000-
/O.EXT.KHGX.FF.W.0005.000000T0000Z-210516T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Houston/Galveston TX
103 PM CDT Sun May 16 2021

The National Weather Service in League City has extended the

* Flash Flood Warning for...
  Northern Jackson County in south central Texas...
  Southwestern Brazoria County in southeastern Texas...
  Southeastern Colorado County in southeastern Texas...
  Northern Matagorda County in southeastern Texas...
  Southern Wharton County in southeastern Texas...

* Until 300 PM CDT.

* At 103 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 3 and 6 inches of rain 
  have fallen across the area with localized totals of up to 8 to 11 
  inches. Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Bay City, El Campo, Edna, Sweeny, Ganado, Blessing, Markham, Van 
  Vleck, Danevang, Midfield, Louise, Wadsworth, Cordele and Morales.

Additional rainfall amounts up to 2 inches per hour are possible in 
the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 2929 9663 2929 9662 2931 9659 2931 9658
      2903 9560 2875 9587 2902 9684 2903 9684
      2903 9685 2903 9686 2904 9689 2906 9694
      2910 9689 2910 9688 2911 9688 2914 9683
      2920 9674 2925 9668

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...2 INCHES IN 1 HOUR 

$$

Cady

The office that day

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

IssuedProductOfficeCountiesLasted
May 16, 6:30 AM CDTSpecial Weather StatementHGXMatagorda45 min
May 16, 7:00 AM CDTAreal Flood AdvisoryHGXMatagorda90 min
May 16, 7:41 AM CDTSpecial Weather StatementHGXMatagorda49 min
May 16, 8:32 AM CDTAreal Flood AdvisoryHGXBrazoria, Jackson, Matagorda, Wharton3 hr
May 16, 8:44 AM CDTFlash Flood WarningHGXBrazoria, Jackson, Matagorda, Wharton3 hr
May 16, 9:03 AM CDTFlash Flood WatchHGXAustin, Brazoria, Colorado, Fort Bend, Jackson, Matagorda and 2 more7 hr
May 16, 9:11 AM CDTAreal Flood AdvisoryHGXHarris64 min
May 16, 9:14 AM CDTSpecial Weather StatementHGXHarris46 min
May 16, 9:35 AM CDTFlash Flood WarningHGXColorado, Jackson, Wharton115 min
May 16, 11:37 AM CDTRiver Flood WarningHGXJackson, Wharton29 hr
May 16, 11:39 AM CDTRiver Flood WarningHGXMatagorda, Wharton6 days
May 16, 12:06 PM CDTSpecial Marine WarningHGX24 min
May 16, 2:07 PM CDTSpecial Weather StatementHGXMatagorda38 min
May 16, 2:13 PM CDTFlash Flood WarningHGXJackson, Matagorda92 min
May 16, 2:31 PM CDTSpecial Marine WarningHGX44 min
May 16, 2:47 PM CDTSpecial Weather StatementHGXMatagorda43 min
May 16, 3:08 PM CDTFlash Flood WarningHGXBrazoria, Matagorda, Wharton82 min
May 16, 3:24 PM CDTSpecial Weather StatementHGXMatagorda51 min
May 16, 3:31 PM CDTRiver Flood WarningHGXJackson22 hr
May 16, 3:31 PM CDTRiver Flood WarningHGXJackson, Wharton11 hr
May 16, 3:46 PM CDTFlash Flood WarningHGXMatagorda59 min
May 16, 5:04 PM CDTAreal Flood WarningHGXMatagorda101 min
May 16, 5:19 PM CDTSpecial Marine WarningHGX56 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.