Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 788

May 28, 202118 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 28, 2021, 3:42 PM CDT for 18 counties in Texas. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
May 28, 2021, 3:42 PM CDT (20:42 UTC)
Expired
May 28, 2021, 5:15 PM CDT
In force
93 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 218

Counties Bell County, TX, Brazos County, TX, Brown County, TX, Burleson County, TX, Burnet County, TX, Comanche County, TX, Coryell County, TX, Erath County, TX, Falls County, TX, Hamilton County, TX, Lampasas County, TX, Lee County, TX, McLennan County, TX, Milam County, TX, Mills County, TX, Robertson County, TX, San Saba County, TX, Williamson County, TX

The radar

The Ft Hood radar (KGRK), 98 km from the middle of the area, began a volume at 20:42 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 8.7 hours before the alert went out and 175 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, Fort Worth, TX at 12:00Z on 2021-05-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 313 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Worth, TX at 12:00Z on 2021-05-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 square meters per square second.19395878Sfc1 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
313 J/kg
Mixed-layer CIN
-386 J/kg
Mixed-layer LCL
694 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
37 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.0

Open this sounding in Storm Lab

The text

As transmitted.

677 
ACUS11 KWNS 282042
SWOMCD
SPC MCD 282042 
TXZ000-282215-

Mesoscale Discussion 0788
NWS Storm Prediction Center Norman OK
0342 PM CDT Fri May 28 2021

Areas affected...central Texas

Concerning...Severe Thunderstorm Watch 218...

Valid 282042Z - 282215Z

The severe weather threat for Severe Thunderstorm Watch 218
continues.

SUMMARY...Severe risk continues locally, within WW 218.

DISCUSSION...Latest radar loop shows that the storm which crossed
Coryell County -- likely producing large hail -- has weakened some
and moved east-southeastward into McLennan County.  Meanwhile,
fairly widespread  -- but currently sub-severe -- storms continue
across portions of the watch.  With a favorably unstable airmass --
particularly across southern and eastern portions of the watch which
have been spared of convective contamination -- still in place, risk
for large hail as well as locally stronger/damaging wind gusts
remains evident.  Convection appears to be increasing just west of
the watch, and as it evolves/spreads eastward, southwestern portions
of the WW may be a focus for greater short-term risk.

..Goss.. 05/28/2021

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

ATTN...WFO...HGX...FWD...EWX...SJT...

LAT...LON   32069911 32389837 30719584 30179671 30989911 32069911

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 27, 10:24 PM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Haskell, Jack, Knox and 7 more96 min
May 28, 2:33 AM CDTMesoscale DiscussionSPCCollin, Denton, Hunt, Rockwall, Wise117 min
May 28, 5:10 AM CDTMesoscale DiscussionSPCBriscoe, Castro, Childress, Cottle, Floyd, Foard and 7 more2 hr
May 28, 11:16 AM CDTMesoscale DiscussionSPCBell, Bosque, Brazos, Brown, Burleson, Coleman and 19 more89 min
May 28, 12:14 PM CDTSevere Thunderstorm WatchSPCBell, Bosque, Brazos, Burleson, Burnet, Comanche and 22 more7 hr
May 28, 12:49 PM CDTMesoscale DiscussionSPCBrewster, Pecos, Presidio, Terrell86 min
May 28, 1:03 PM CDTMesoscale DiscussionSPCAndrews, Bailey, Borden, Cochran, Dawson, Ector and 11 more57 min
May 28, 2:33 PM CDTMesoscale DiscussionSPCAndrews, Borden, Brown, Coke, Coleman, Concho and 35 more117 min
May 28, 2:45 PM CDTSevere Thunderstorm WatchSPCBrewster, Culberson, Jeff Davis, Loving, Pecos, Reeves and 3 more9 hr
May 28, 3:41 PM CDTSevere Thunderstorm WatchSPCAndrews, Brown, Coke, Coleman, Concho, Crane and 20 more8 hr
May 28, 5:54 PM CDTMesoscale DiscussionSPCAtascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 29 more96 min
May 28, 6:20 PM CDTSevere Thunderstorm WatchSPCAtascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 32 more5 hr
May 28, 6:49 PM CDTMesoscale DiscussionSPCBailey, Deaf Smith, Parmer86 min

Nearby

Mesoscale Discussions in Texas, 2021Every 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.