Alert archive / Texas / Flash Flood Warnings in 2021

Flash Flood Warning 37, NWS San Angelo, TX

August 17, 2021Kimble County, Texas

NWS San Angelo, TX issued this flash flood warning at Aug 17, 2021, 4:24 PM CDT for Kimble County, Texas. It was in force for 111 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 17, 2021, 4:24 PM CDT (21:24 UTC)
Expired
Aug 17, 2021, 6:15 PM CDT
In force
111 min
Issued by
NWS San Angelo, TX
Area
Storm-based polygon
Flood severity
None

County Kimble County, TX

The radar

The San Angelo radar (KSJT), 134 km from the middle of the area, began a volume at 21:27 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.

The nearest sounding before it

Del Rio, TX (KDRT), launched 12:00Z, 9.4 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-pSkew-T log-p diagram, Del Rio, TX at 12:00Z on 2021-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1588 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, Del Rio, TX at 12:00Z on 2021-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 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
1588 J/kg
Mixed-layer CIN
-51 J/kg
Mixed-layer LCL
890 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
102 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

As transmitted.

379 
WGUS54 KSJT 172124
FFWSJT
TXC267-172315-
/O.NEW.KSJT.FF.W.0037.210817T2124Z-210817T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in San Angelo has issued a

* Flash Flood Warning for...
  Southern and Southeastern Kimble County in west central Texas...

* Until 615 PM CDT.

* At 419 PM CDT, National Weather Service radar indicated a cluster 
  of thunderstorms with very heavy rainfall across the warned area. 
  The cluster of storms was moving slowly to the east. This cluster 
  of storms has a history of producing rainfall of 2 to 3.5 inches. 
  This intense rainfall is expected to cause flash flooding. 

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  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 flooding include...
  Junction, Segovia, South Llano River State Park, Us-
  83 Near The Kerr-Kimble County Line, I-10 Near The Kimble-
  Kerr County Line and The Intersection Of I-10 And Us 290.

This includes the following streams and drainages...
Sycamore Creek, Little Devils River, Allen Creek, Salt Creek, White
Oak Creek, Dry Cedar Creek, Chalk Creek, Llano River, Bogs, The,
James River, North Llano River, Paint Creek, Johnson Fork, Burnt
Branch, South Llano River, Cedar Creek, Falls Prong, Tobe Branch, Joy
Creek, Middle Sycamore Creek, East Sycamore Creek and Shin Oak Creek.

This includes the following low water crossings ...
    Park Road 73 crossing South Llano River...
    FM 2169 crossing Johnson Fork Creek...
    RM 385 crossing Perdenales River...
    RM 385 crossing Falls Prong...
    Old Segovia Rd. crossing Johnson Fork...
    County Road 430 crossing Johnson Fork...
    Flatrock Ln. crossing South Llano River...
    County Road 430 crossing Joy Creek...
    KC 451 crossing Johnson Fork and
    crossings along County Road 410.
Do not drive through these low water crossings or any other
low water crossing with water flowing across the roadway.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3050 9982 3050 9930 3029 9930 3029 9990
      3030 9990

FLASH FLOOD...RADAR INDICATED

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 5:34 AM CDTAreal Flood AdvisorySJTIrion, Sterling, Tom Green2 hr
Aug 17, 6:08 AM CDTFlash Flood WarningSJTIrion, Tom Green112 min
Aug 17, 6:55 AM CDTFlash Flood Warning Considerable damage threatSJTTom Green110 min
Aug 17, 7:10 AM CDTFlash Flood Warning Considerable damage threatSJTIrion3 hr
Aug 17, 7:33 AM CDTFlash Flood Warning Considerable damage threatSJTIrion, Tom Green3 hr
Aug 17, 7:47 AM CDTFlash Flood Warning Considerable damage threatSJTIrion, Tom Green3 hr
Aug 17, 8:39 AM CDTFlash Flood Warning Considerable damage threatSJTTom Green111 min
Aug 17, 8:55 AM CDTFlash Flood Warning Considerable damage threatSJTTom Green3 hr
Aug 17, 9:04 AM CDTAreal Flood AdvisorySJTSchleicher3 hr
Aug 17, 9:36 AM CDTFlash Flood Warning Considerable damage threatSJTSchleicher3 hr
Aug 17, 9:54 AM CDTRiver Flood WarningSJTIrion, Tom Green22 hr
Aug 17, 10:31 AM CDTAreal Flood WarningSJTIrion, Tom Green3 hr
Aug 17, 10:36 AM CDTAreal Flood AdvisorySJTConcho, Menard3 hr
Aug 17, 11:10 AM CDTAreal Flood AdvisorySJTMcCulloch3 hr
Aug 17, 12:19 PM CDTFlash Flood Warning Considerable damage threatSJTSchleicher3 hr
Aug 17, 12:34 PM CDTFlash Flood WatchSJTCoke, Concho, Crockett, Irion, Menard, Runnels and 4 more16 hr
Aug 17, 12:49 PM CDTFlash Flood Warning Considerable damage threatSJTSchleicher, Sutton3 hr
Aug 17, 1:50 PM CDTSpecial Weather StatementSJTKimble40 min
Aug 17, 2:26 PM CDTFlash Flood Warning Considerable damage threatSJTKimble, Sutton2 hr
Aug 17, 3:10 PM CDTAreal Flood WarningSJTIrion, Tom Green6 hr
Aug 17, 6:33 PM CDTRiver Flood WarningSJTTom Green10 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.