Alert archive / Texas / Flash Flood Warnings in 2021

Flash Flood Warning 32, NWS Shreveport, LA

August 18, 2021Smith County, Texas

NWS Shreveport, LA issued this flash flood warning at Aug 18, 2021, 5:35 AM CDT for Smith County, Texas. It was in force for 3 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
Aug 18, 2021, 5:35 AM CDT (10:35 UTC)
Expired
Aug 18, 2021, 8:45 AM CDT
In force
3 hr
Issued by
NWS Shreveport, LA
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Smith County, TX

The radar

The Shreveport radar (KSHV), 150 km from the middle of the area, began a volume at 10:39 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
Aug 18, 6:10 AM CDTFLASH FLOOD1 N Tyler, TXNUMEROUS ROADS FLOODED IN THE CITY OF TYLER.
Aug 18, 6:10 AM CDTFLASH FLOODNew Chapel Hill, TXWATER RESCUE IN NEW CHAPEL HILL AT THE INTERSECTION OF CR-289 AND TX-64.
Aug 18, 6:22 AM CDTFLASH FLOOD3 Ese Tyler, TXFLOODING ON CALLOWAY RD AND AT THE INTERSECTION OF TX-110 AND TX-323, RELAYED VIA SOCIAL MEDIA.

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, 10.6 hours before the alert went out and 159 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 2021-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1110 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, Shreveport, LA at 00:00Z on 2021-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 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
1110 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
1333 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
77 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8

Open this sounding in Storm Lab

The text

As transmitted.

965 
WGUS54 KSHV 181035
FFWSHV
TXC423-181345-
/O.NEW.KSHV.FF.W.0032.210818T1035Z-210818T1345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Shreveport LA
535 AM CDT Wed Aug 18 2021

The National Weather Service in Shreveport has issued a

* Flash Flood Warning for...
  Smith County in northeastern Texas...

* Until 845 AM CDT.

* At 535 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen in Tyler. 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...
  Tyler, Whitehouse, Lindale, Noonday, New Chapel Hill, Winona and 
  Carroll.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3256 9559 3247 9505 3217 9511 3217 9537
      3218 9546 3220 9546 3224 9549 3225 9547
      3226 9547 3229 9545 3233 9546 3236 9545
      3247 9559

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

04
2 follow-up statements
715 
WGUS74 KSHV 181120
FFSSHV

Flash Flood Statement
National Weather Service Shreveport LA
620 AM CDT Wed Aug 18 2021

TXC423-181345-
/O.CON.KSHV.FF.W.0032.000000T0000Z-210818T1345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Smith TX-
620 AM CDT Wed Aug 18 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 AM CDT THIS 
MORNING FOR SMITH COUNTY...

At 620 AM CDT, local law enforcement reported flash flooding in 
Tyler. Between 2 and 5 inches of rain have fallen. Additional 
rainfall amounts of 1 to 2 inches are possible in the warned area. 
Flash flooding is already occurring.

HAZARD...Life threatening flash flooding. Heavy rain producing
         flash flooding.

SOURCE...Law enforcement reported.

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

Some locations that will experience flash flooding include...
  Tyler, Whitehouse, Lindale, Noonday, New Chapel Hill, Winona and 
  Carroll.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3256 9559 3247 9505 3217 9511 3217 9537
      3218 9546 3220 9546 3224 9549 3225 9547
      3226 9547 3229 9545 3233 9546 3236 9545
      3247 9559

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

04
193 
WGUS74 KSHV 181208
FFSSHV

Flash Flood Statement
National Weather Service Shreveport LA
708 AM CDT Wed Aug 18 2021

TXC423-181345-
/O.CON.KSHV.FF.W.0032.000000T0000Z-210818T1345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Smith TX-
708 AM CDT Wed Aug 18 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 AM CDT THIS 
MORNING FOR SMITH COUNTY...

At 708 AM CDT, local law enforcement reported flash flooding with 
water rescues in Tyler and New Chapel Hill. Between 3 and 6 inches 
of rain have fallen. Additional rainfall amounts up to 1 inch are 
possible in the warned area. Flash flooding is already occurring.

HAZARD...Life threatening flash flooding. Heavy rain producing
         flash flooding.

SOURCE...Law enforcement reported.

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

Some locations that will experience flash flooding include...
  Tyler, Whitehouse, Lindale, Noonday, New Chapel Hill, Winona and 
  Carroll.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3256 9559 3247 9505 3217 9511 3217 9537
      3218 9546 3220 9546 3224 9549 3225 9547
      3226 9547 3229 9545 3233 9546 3236 9545
      3247 9559

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

04

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 7:14 PM CDTSpecial Weather StatementSHVSmith31 min
Aug 17, 7:33 PM CDTSevere Thunderstorm WarningSHVSmith, Wood57 min
Aug 17, 7:58 PM CDTSpecial Weather StatementSHVWood62 min
Aug 17, 8:09 PM CDTSpecial Weather StatementSHVSmith51 min
Aug 18, 3:00 AM CDTAreal Flood AdvisorySHVPanola, Rusk, Shelby3 hr
Aug 18, 4:46 AM CDTAreal Flood AdvisorySHVSmith3 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.