Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 512

May 3, 202112 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 3, 2021, 9:10 PM CDT for 12 counties in Texas. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: May 3, 2021, 9:10 PM CDT (02:10 UTC)
Expired: May 3, 2021, 10:45 PM CDT
In force: 95 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 134

Counties Callahan County, TX, Eastland County, TX, Fisher County, TX, Haskell County, TX, Jones County, TX, Nolan County, TX, Palo Pinto County, TX, Shackelford County, TX, Stephens County, TX, Taylor County, TX, Throckmorton County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 40 km from the middle of the area, began a volume at 02:11 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

Fort Worth, TX (KFWD), launched 00:00Z, 2.2 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-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: 3299 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 1213 m above ground
0-6 km bulk shear: 58 kt
0-1 km storm-relative helicity: 150 m²/s²
0-3 km storm-relative helicity: 143 m²/s²
Significant tornado parameter: 2.6
Supercell composite: 13.9

Open this sounding in Storm Lab

The text

As transmitted.

357 
ACUS11 KWNS 040211
SWOMCD
SPC MCD 040210 
TXZ000-040345-

Mesoscale Discussion 0512
NWS Storm Prediction Center Norman OK
0910 PM CDT Mon May 03 2021

Areas affected...Portions of west-central TX

Concerning...Severe Thunderstorm Watch 134...

Valid 040210Z - 040345Z

The severe weather threat for Severe Thunderstorm Watch 134
continues.

SUMMARY...The potential for very large (2 to 3 inch) hail should
continue in the short term with a robust supercell moving eastward.
Severe wind gusts around 60-65 mph may also occur.

DISCUSSION...A long-lived supercell which recently produced baseball
sized hail (2.75") and a measured 61 mph wind gust in Fisher County
TX will likely continue eastward across west-central TX over the
next couple of hours. Even though this storm will remain
post-frontal, steep mid-level lapse rates and increasing low-level
moisture with eastward extent will likely support continued storm
intensity, with MUCAPE of 1000-2000 J/kg present downstream.
Isolated very large hail will this supercell will remain the primary
concern in the short term, but severe wind gusts may also occur
given the favorable velocity signature from KDYX.

..Gleason.. 05/04/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...FWD...SJT...

LAT...LON   32320058 32860058 32919994 33259991 33239808 32629822
            32309875 32270018 32320058

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 3, 7:01 PM CDT	Severe Thunderstorm Watch	SPC	Atascosa, Bandera, Bexar, Blanco, Burnet, Comal and 9 more	4 hr
May 3, 7:38 PM CDT	Mesoscale Discussion	SPC	Bosque, Collin, Dallas, Denton, Ellis, Fannin and 6 more	97 min
May 3, 8:30 PM CDT	Mesoscale Discussion	SPC	Bexar, Blanco, Comal, Guadalupe, Hays, Kendall	60 min
May 3, 8:38 PM CDT	Mesoscale Discussion	SPC	Bowie, Camp, Cass, Gregg, Marion, Morris and 4 more	2 hr
May 3, 9:10 PM CDT	Severe Thunderstorm Watch	SPC	Bowie, Camp, Cass, Cherokee, Franklin, Gregg and 10 more	7 hr
May 3, 9:52 PM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Coryell, Ellis, Falls, Freestone and 12 more	53 min
May 3, 10:22 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bell, Collin, Cooke, Dallas, Delta and 28 more	5 hr
May 3, 11:34 PM CDT	Mesoscale Discussion	SPC	Bowie, Camp, Cass, Falls, Franklin, Freestone and 12 more	86 min
May 4, 6:44 AM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Brazos, Burleson, Camp, Cass and 23 more	2 hr
May 4, 8:11 AM CDT	Severe Thunderstorm Watch	SPC	Angelina, Austin, Brazos, Burleson, Chambers, Colorado and 22 more	8 hr

Nearby

Mesoscale Discussions in Texas, 2021 Every mesoscale discussion 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.