Alert archive / Texas / Flash Flood Warnings in 2021

Flash Flood Warning 28, NWS San Angelo, TX

August 17, 2021Irion County, Texas

NWS San Angelo, TX issued this flash flood warning at Aug 17, 2021, 7:10 AM CDT for Irion County, Texas. It was in force for 3 hr. 2 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 17, 2021, 7:10 AM CDT (12:10 UTC)
Expired: Aug 17, 2021, 10:00 AM CDT
In force: 3 hr
Issued by: NWS San Angelo, TX
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Irion County, TX

The radar

The San Angelo radar (KSJT), 49 km from the middle of the area, began a volume at 12:14 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, 8:25 AM CDT	FLASH FLOOD	Arden, TX	THE TOM GREEN COUNTY SHERIFFS OFFICE REPORTED FLOODED ROADS IN THE TOWN OF ARDEN.
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, 0.2 hours before the alert went out and 131 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.

218 
WGUS54 KSJT 171210
FFWSJT
TXC235-171500-
/O.NEW.KSJT.FF.W.0028.210817T1210Z-210817T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in San Angelo has issued a

* Flash Flood Warning for...
  Central Irion County in west central Texas...

* Until 1000 AM CDT.

* At 708 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2.5 and 3 inches of 
  rain have fallen. Flash flooding is ongoing or expected to begin 
  shortly. Additional heavy rainfall will cause flash flooding of 
  creeks, 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...
  Mertzon, Sherwood and Arden.

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 3142 10118 3148 10074 3120 10079 3122 10117

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

$$

21

1 follow-up statement

699 
WGUS74 KSJT 171324
FFSSJT

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

TXC235-171500-
/O.CON.KSJT.FF.W.0028.000000T0000Z-210817T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Irion TX-
824 AM CDT Tue Aug 17 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 AM CDT THIS 
MORNING FOR CENTRAL IRION COUNTY...

At 818 AM CDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1.5 and 3 inches of rain have 
fallen mainly near and just southeast of Mertzon . Flash flooding is 
ongoing or expected to begin shortly. Additional heavy rainfall will 
cause flash flooding of creeks, low water crossings and streets.

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...
  Mertzon, Sherwood and Arden.

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 3142 10118 3148 10074 3120 10079 3122 10117

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, 7:33 AM CDT	Flash Flood Warning Considerable damage threat	SJT	Irion, Tom Green	3 hr
Aug 17, 7:47 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.