Alert archive / Texas / Flash Flood Warnings in 2021

Flash Flood Warning 30, NWS San Angelo, TX

August 17, 2021Irion County, Tom Green County, Texas

NWS San Angelo, TX issued this flash flood warning at Aug 17, 2021, 7:47 AM CDT for Irion County, Tom Green County, Texas. It was in force for 3 hr. 1 report 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 17, 2021, 7:47 AM CDT (12:47 UTC)
Expired: Aug 17, 2021, 10:45 AM CDT
In force: 3 hr
Issued by: NWS San Angelo, TX
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

Counties Irion County, TX, Tom Green County, TX

The radar

The San Angelo radar (KSJT), 34 km from the middle of the area, began a volume at 12:51 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

Time	Report	Where	Remark
Aug 17, 8:55 AM CDT	FLASH FLOOD	Mertzon, TX	A SOCIAL MEDIA POST INDICATED SEVERAL STREETS AND LOW WATER CROSSINGS FLOODED IN MERTZON.

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

The nearest sounding before it

Midland Regional, TX (KMAF), launched 12:00Z, 0.8 hours before the alert went out and 160 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 134 J/kg
Mixed-layer CIN: -49 J/kg
Mixed-layer LCL: 779 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 59 m²/s²
0-3 km storm-relative helicity: 91 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

661 
WGUS54 KSJT 171247
FFWSJT
TXC235-451-171545-
/O.NEW.KSJT.FF.W.0030.210817T1247Z-210817T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Angelo TX
747 AM CDT Tue Aug 17 2021

The National Weather Service in San Angelo has issued a

* Flash Flood Warning for...
  Southeastern Irion County in west central Texas...
  South Central Tom Green County in west central Texas...

* Until 1045 AM CDT.

* At 746 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly. Additional heavy rainfall will cause flash flooding of 
  streams, low water crossings and roads.

  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...
  San Angelo, Mertzon, Christoval, Knickerbocker, Sherwood, 
  Tankersley and Twin Buttes Reservoir.

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 3108 10097 3127 10097 3138 10052 3109 10042

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

$$

21

1 follow-up statement

082 
WGUS74 KSJT 171432
FFSSJT

Flash Flood Statement
National Weather Service San Angelo TX
932 AM CDT Tue Aug 17 2021

TXC235-451-171545-
/O.CON.KSJT.FF.W.0030.000000T0000Z-210817T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Irion TX-Tom Green TX-
932 AM CDT Tue Aug 17 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1045 AM CDT THIS 
MORNING FOR SOUTHEASTERN IRION AND SOUTH CENTRAL TOM GREEN 
COUNTIES...

At 929 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 3 inches of rain have 
fallen across south central Tom Green County around Christoval. 
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...
  San Angelo, Mertzon, Christoval, Knickerbocker, Sherwood, 
  Tankersley and Twin Buttes Reservoir.

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 3108 10097 3127 10097 3138 10052 3109 10042

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

$$

21

The office that day

Everything else NWS San Angelo, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 17, 5:34 AM CDT	Areal Flood Advisory	SJT	Irion, Sterling, Tom Green	2 hr
Aug 17, 6:08 AM CDT	Flash Flood Warning	SJT	Irion, Tom Green	112 min
Aug 17, 6:55 AM CDT	Flash Flood Warning Considerable damage threat	SJT	Tom Green	110 min
Aug 17, 7:10 AM CDT	Flash Flood Warning Considerable damage threat	SJT	Irion	3 hr
Aug 17, 7:33 AM CDT	Flash Flood Warning Considerable damage threat	SJT	Irion, Tom Green	3 hr
Aug 17, 8:39 AM CDT	Flash Flood Warning Considerable damage threat	SJT	Tom Green	111 min
Aug 17, 8:55 AM CDT	Flash Flood Warning Considerable damage threat	SJT	Tom Green	3 hr
Aug 17, 9:04 AM CDT	Areal Flood Advisory	SJT	Schleicher	3 hr
Aug 17, 9:36 AM CDT	Flash Flood Warning Considerable damage threat	SJT	Schleicher	3 hr
Aug 17, 9:54 AM CDT	River Flood Warning	SJT	Irion, Tom Green	22 hr
Aug 17, 10:31 AM CDT	Areal Flood Warning	SJT	Irion, Tom Green	3 hr
Aug 17, 10:36 AM CDT	Areal Flood Advisory	SJT	Concho, Menard	3 hr
Aug 17, 11:10 AM CDT	Areal Flood Advisory	SJT	McCulloch	3 hr
Aug 17, 12:19 PM CDT	Flash Flood Warning Considerable damage threat	SJT	Schleicher	3 hr
Aug 17, 12:34 PM CDT	Flash Flood Watch	SJT	Coke, Concho, Crockett, Irion, Menard, Runnels and 4 more	16 hr
Aug 17, 12:49 PM CDT	Flash Flood Warning Considerable damage threat	SJT	Schleicher, Sutton	3 hr
Aug 17, 1:50 PM CDT	Special Weather Statement	SJT	Kimble	40 min
Aug 17, 2:26 PM CDT	Flash Flood Warning Considerable damage threat	SJT	Kimble, Sutton	2 hr
Aug 17, 3:10 PM CDT	Areal Flood Warning	SJT	Irion, Tom Green	6 hr
Aug 17, 4:24 PM CDT	Flash Flood Warning	SJT	Kimble	111 min
Aug 17, 6:33 PM CDT	River Flood Warning	SJT	Tom Green	10 hr

Nearby

Flash Flood Warnings in Texas, 2021 Every 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.