Alert archive / Texas / Flash Flood Warnings in 2021

Flash Flood Warning 52, NWS San Angelo, TX

October 1, 2021Mason County, Texas

NWS San Angelo, TX issued this flash flood warning at Oct 1, 2021, 12:12 AM CDT for Mason County, Texas. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Oct 1, 2021, 12:12 AM CDT (05:12 UTC)
Expired
Oct 1, 2021, 2:15 AM CDT
In force
2 hr
Issued by
NWS San Angelo, TX
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Mason County, TX

The radar

The San Angelo radar (KSJT), 142 km from the middle of the area, began a volume at 05:12 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 00:00Z, 5.2 hours before the alert went out and 221 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 00:00Z on 2021-10-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2844 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 00:00Z on 2021-10-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 50 square meters per square second.193958Sfc1 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
2844 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
1576 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
50 m²/s²
0-3 km storm-relative helicity
135 m²/s²
Significant tornado parameter
0.6
Supercell composite
7.3

Open this sounding in Storm Lab

The text

As transmitted.

267 
WGUS54 KSJT 010512
FFWSJT
TXC319-010715-
/O.NEW.KSJT.FF.W.0052.211001T0512Z-211001T0715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service San Angelo TX
1212 AM CDT Fri Oct 1 2021

The National Weather Service in San Angelo has issued a

* Flash Flood Warning for...
  Mason County in west central Texas...

* Until 215 AM CDT.

* At 1210 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 3 and 4 inches of rain 
  have fallen 10 miles southwest of Mason. Additional rainfall 
  amounts of 1 to 2 inches are likely in the warned area as storms 
  move east across Mason County. 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...
  Mason, Art, Hedwigs Hill, Hilda, Grit, Streeter, Katemcy, Camp 
  Air, Loyal Valley, Fredonia, Pontotoc, Koockville, The 
  Intersection Of Highway 29 And Ranch Road 1222 and Us-87 Near The 
  Mason-Gillespie County Line.

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.

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

&&

LAT...LON 3050 9941 3094 9939 3094 9909 3092 9909
      3092 9896 3050 9896

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

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 30, 7:14 PM CDTSpecial Weather StatementSJTCrockett46 min
Sep 30, 7:32 PM CDTSpecial Weather StatementSJTMcCulloch43 min
Sep 30, 7:49 PM CDTAreal Flood AdvisorySJTMcCulloch, San Saba3 hr
Sep 30, 8:09 PM CDTFlash Flood Warning Considerable damage threatSJTMcCulloch, San Saba3 hr
Sep 30, 9:54 PM CDTAreal Flood AdvisorySJTKimble, McCulloch, Mason, Menard, Schleicher, Sutton3 hr
Sep 30, 10:26 PM CDTSevere Thunderstorm WarningSJTKimble, Mason, Menard49 min
Sep 30, 11:27 PM CDTSpecial Weather StatementSJTMason48 min
Oct 1, 2:32 AM CDTAreal Flood AdvisorySJTSan Saba3 hr
Oct 1, 6:33 PM CDTSpecial Weather StatementSJTCrockett42 min

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.