Alert archive / Texas / Flash Flood Warnings in 2023

Flash Flood Warning 21, NWS Shreveport, LA

May 11, 20235 counties in Texas

NWS Shreveport, LA issued this flash flood warning at May 11, 2023, 1:37 AM CDT for 5 counties in Texas. It was in force for 5 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 11, 2023, 1:37 AM CDT (06:37 UTC)
Expired
May 11, 2023, 6:30 AM CDT
In force
5 hr
Issued by
NWS Shreveport, LA
Area
Storm-based polygon
Flood severity
None

Counties Cherokee County, TX, Nacogdoches County, TX, Rusk County, TX, San Augustine County, TX, Shelby County, TX

The radar

The Shreveport radar (KSHV), 135 km from the middle of the area, began a volume at 06:38 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.

What was reported inside it

TimeReportWhereRemark
May 11, 2:45 AM CDTFLASH FLOOD1 Ssw Nacogdoches, TXCORRECTS PREVIOUS FLASH FLOOD REPORT FROM 1 SSW NACOGDOCHES. SOUTH SIDE OF NACOGDOCHES STREETS ARE CLOSED DUE TO FLOODING. FLOODING OF ROADS WIDESPREAD ACROSS THE COUNTY.
May 11, 2:55 AM CDTFLASH FLOOD3 Ssw Nacogdoches, TXSHERIFF DEPARTMENTS REPORTS ROAD COMPLETELY UNDER WATER AROUND THE 3500 BLOCK OF SOUTH STREET IN NACOGDOCHES, TX. ALSO, A WATER RESCUE WAS UNDERWAY ON A STALLED VEHICLE.
May 11, 5:45 AM CDTFLASH FLOODTimpson, TXHWY 96 NORTH OF TIMPSON IS CLOSED DUE TO FLOODING. NUMEROUS ROADS CLOSED IN TIMPSON.

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

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 6.6 hours before the alert went out and 144 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, Shreveport, LA at 00:00Z on 2023-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 50 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, Shreveport, LA at 00:00Z on 2023-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 104 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
50 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
856 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
104 m²/s²
0-3 km storm-relative helicity
122 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

634 
WGUS54 KSHV 110637
FFWSHV
TXC073-347-401-405-419-110930-
/O.NEW.KSHV.FF.W.0021.230511T0637Z-230511T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Shreveport LA
137 AM CDT Thu May 11 2023

The National Weather Service in Shreveport has issued a

* Flash Flood Warning for...
  Nacogdoches County in eastern Texas...
  Northwestern San Augustine County in eastern Texas...
  Western Shelby County in eastern Texas...
  Southeastern Cherokee County in northeastern Texas...
  Southern Rusk County in northeastern Texas...

* Until 430 AM CDT.

* At 137 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. The expected rainfall rate is 1 
  to 2 inches in 1 hour. Additional rainfall amounts of 2 to 4 
  inches are possible in the warned area. Flash flooding is ongoing 
  or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  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...
  Nacogdoches, Jacksonville, Rusk, Center, San Augustine, Alto, 
  Tenaha, Timpson, Garrison, Wells, Trawick, Melrose, Martinsville, 
  Woden, Douglass, Sacul, New Salem, Forest, Morrill and Ponta.

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.

&&

LAT...LON 3195 9523 3195 9407 3144 9414 3154 9484
      3145 9505 3147 9507 3147 9510 3152 9510
      3154 9514

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

$$

13
2 follow-up statements
421 
WGUS74 KSHV 110728
FFSSHV

Flash Flood Statement
National Weather Service Shreveport LA
228 AM CDT Thu May 11 2023

TXC073-347-401-405-419-110930-
/O.CON.KSHV.FF.W.0021.000000T0000Z-230511T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cherokee TX-Nacogdoches TX-Rusk TX-San Augustine TX-Shelby TX-
228 AM CDT Thu May 11 2023

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 AM CDT EARLY THIS 
MORNING FOR NACOGDOCHES, NORTHWESTERN SAN AUGUSTINE, WESTERN SHELBY, 
SOUTHEASTERN CHEROKEE AND SOUTHERN RUSK COUNTIES...

At 228 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. The expected rainfall rate is 1 to 2 
inches in 1 hour. Additional rainfall amounts of 1 to 3 inches are 
possible in the warned area. Flash flooding is ongoing or expected 
to begin shortly.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Nacogdoches, Timpson, Garrison, Trawick, Melrose, Martinsville, 
  Douglass, Sacul, New Salem, Appleby, and Cushing.

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.

&&

LAT...LON 3195 9523 3195 9407 3144 9414 3154 9484
      3145 9505 3147 9507 3147 9510 3152 9510
      3154 9514

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

20
863 
WGUS54 KSHV 110919
FFWSHV
TXC073-347-401-405-419-111130-
/O.EXT.KSHV.FF.W.0021.000000T0000Z-230511T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Shreveport LA
419 AM CDT Thu May 11 2023

The National Weather Service in Shreveport has extended the

* Flash Flood Warning for...
  Nacogdoches County in eastern Texas...
  Northwestern San Augustine County in eastern Texas...
  Western Shelby County in eastern Texas...
  Southeastern Cherokee County in northeastern Texas...
  Southern Rusk County in northeastern Texas...

* Until 630 AM CDT.

* At 419 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 5 inches of rain 
  have fallen. The expected rainfall rate is 1 to 2 inches in 1 
  hour. Additional rainfall amounts of 1 to 2 inches are possible in 
  the warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Nacogdoches, Jacksonville, Rusk, Center, San Augustine, Alto, 
  Tenaha, Timpson, Garrison, Wells, Trawick, Melrose, Martinsville, 
  Woden, Douglass, Sacul, New Salem, Forest, Morrill and Ponta.

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.

&&

LAT...LON 3195 9523 3195 9407 3144 9414 3154 9484
      3145 9505 3147 9507 3147 9510 3152 9510
      3154 9514

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

19

The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 10, 8:35 PM CDTSpecial Weather StatementSHVShelby25 min
May 10, 10:53 PM CDTSpecial Weather StatementSHVAngelina37 min
May 11, 2:50 AM CDTSpecial Weather StatementSHVNacogdoches40 min
May 11, 3:15 AM CDTSevere Thunderstorm WarningSHVNacogdoches, San Augustine, Shelby60 min
May 11, 5:10 AM CDTSevere Thunderstorm WarningSHVNacogdoches, Panola, Rusk, Shelby50 min
May 11, 5:49 AM CDTFlash Flood WarningSHVPanola, Rusk, Shelby6 hr
May 11, 6:47 AM CDTSpecial Weather StatementSHVPanola28 min
May 11, 6:49 AM CDTSpecial Weather StatementSHVPanola41 min
May 11, 7:44 AM CDTFlash Flood WarningSHVPanola, Shelby6 hr
May 11, 8:17 AM CDTAreal Flood WarningSHVNacogdoches, Rusk, Shelby11 hr
May 11, 8:25 AM CDTSevere Thunderstorm WarningSHVShelby65 min
May 11, 8:32 AM CDTRiver Flood WarningSHVNacogdoches, Rusk, San Augustine, Shelby8 days
May 11, 8:32 AM CDTRiver Flood WarningSHVSabine, San Augustine12 hr
May 11, 8:33 AM CDTRiver Flood WarningSHVNacogdoches, Rusk51 hr
May 11, 8:46 AM CDTFlash Flood Warning Considerable damage threatSHVNacogdoches3 hr
May 11, 11:46 AM CDTAreal Flood WarningSHVPanola, Rusk, Shelby6 hr
May 11, 1:39 PM CDTAreal Flood WarningSHVPanola, Shelby4 hr

Nearby

Flash Flood Warnings in Texas, 2023Every flash flood warning in 2023

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.