Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 781

May 28, 20215 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 28, 2021, 2:33 AM CDT for 5 counties in Texas. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued: May 28, 2021, 2:33 AM CDT (07:33 UTC)
Expired: May 28, 2021, 4:30 AM CDT
In force: 117 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 5%

Counties Collin County, TX, Denton County, TX, Hunt County, TX, Rockwall County, TX, Wise County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 80 km from the middle of the area, began a volume at 07:36 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, 7.6 hours before the alert went out and 57 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: 1480 J/kg
Mixed-layer CIN: -150 J/kg
Mixed-layer LCL: 1331 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 124 m²/s²
0-3 km storm-relative helicity: 203 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 3.7

Open this sounding in Storm Lab

The text

As transmitted.

198 
ACUS11 KWNS 280733
SWOMCD
SPC MCD 280733 
TXZ000-280930-

Mesoscale Discussion 0781
NWS Storm Prediction Center Norman OK
0233 AM CDT Fri May 28 2021

Areas affected...Portions of north TX

Concerning...Severe potential...Watch unlikely 

Valid 280733Z - 280930Z

Probability of Watch Issuance...5 percent

SUMMARY...Damaging winds and hail may continue to occur for a couple
more hours with a long lived supercell early this morning.

DISCUSSION...A long lived supercell continues to move generally
eastward across part of north TX early this morning. Outflow from
earlier storms has surged well south of this storm. But, MUCAPE
around 1500-2000 J/kg is still present to the north of this boundary
and ahead of the supercell. Recent VWPs from the KFWS radar show a
veering and strengthening wind profile with height through mid
levels, and 35-40 kt of effective bulk shear will be sufficient to
support continued storm organization in the short term. The TDFW
radar shows very strong inbound velocities, and there is some
potential for these wind to reach the surface and cause damage as
the storm approaches Denton TX and locations to the east in the next
1-2 hours. Isolated large hail may also occur. Given that there is
only one supercell ongoing at the moment, the overall severe threat
is expected to remain too isolated to justify watch issuance.

..Gleason/Grams.. 05/28/2021

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

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

LAT...LON   33249771 33509741 33439654 33269574 32969580 32839605
            32949687 33089759 33249771

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 27, 10:24 PM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Clay, Haskell, Jack, Knox and 7 more	96 min
May 28, 5:10 AM CDT	Mesoscale Discussion	SPC	Briscoe, Castro, Childress, Cottle, Floyd, Foard and 7 more	2 hr
May 28, 11:16 AM CDT	Mesoscale Discussion	SPC	Bell, Bosque, Brazos, Brown, Burleson, Coleman and 19 more	89 min
May 28, 12:14 PM CDT	Severe Thunderstorm Watch	SPC	Bell, Bosque, Brazos, Burleson, Burnet, Comanche and 22 more	7 hr
May 28, 12:49 PM CDT	Mesoscale Discussion	SPC	Brewster, Pecos, Presidio, Terrell	86 min
May 28, 1:03 PM CDT	Mesoscale Discussion	SPC	Andrews, Bailey, Borden, Cochran, Dawson, Ector and 11 more	57 min
May 28, 2:33 PM CDT	Mesoscale Discussion	SPC	Andrews, Borden, Brown, Coke, Coleman, Concho and 35 more	117 min
May 28, 2:45 PM CDT	Severe Thunderstorm Watch	SPC	Brewster, Culberson, Jeff Davis, Loving, Pecos, Reeves and 3 more	9 hr
May 28, 3:41 PM CDT	Severe Thunderstorm Watch	SPC	Andrews, Brown, Coke, Coleman, Concho, Crane and 20 more	8 hr
May 28, 3:42 PM CDT	Mesoscale Discussion	SPC	Bell, Brazos, Brown, Burleson, Burnet, Comanche and 12 more	93 min
May 28, 5:54 PM CDT	Mesoscale Discussion	SPC	Atascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 29 more	96 min
May 28, 6:20 PM CDT	Severe Thunderstorm Watch	SPC	Atascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 32 more	5 hr
May 28, 6:49 PM CDT	Mesoscale Discussion	SPC	Bailey, Deaf Smith, Parmer	86 min

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.