Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 828
The Storm Prediction Center issued this mesoscale discussion at May 31, 2021, 5:12 PM CDT for 16 counties in Texas. It was in force for 93 min.
The area
The outline as issued.
The facts
- Issued
- May 31, 2021, 5:12 PM CDT (22:12 UTC)
- Expired
- May 31, 2021, 6:45 PM CDT
- In force
- 93 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 230
Counties Bell County, TX, Bosque County, TX, Coryell County, TX, Ellis County, TX, Falls County, TX, Freestone County, TX, Hamilton County, TX, Hill County, TX, Johnson County, TX, Lampasas County, TX, Limestone County, TX, McLennan County, TX, Milam County, TX, Navarro County, TX, Robertson County, TX, Somervell County, TX
The radar
The Ft Hood radar (KGRK), 102 km from the middle of the area, began a volume at 22:15 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 12:00Z, 10.2 hours before the alert went out and 133 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.
- Mixed-layer CAPE
- 10 J/kg
- Mixed-layer CIN
- -109 J/kg
- Mixed-layer LCL
- 647 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 206 m²/s²
- 0-3 km storm-relative helicity
- 212 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted.
582
ACUS11 KWNS 312212
SWOMCD
SPC MCD 312212
TXZ000-312345-
Mesoscale Discussion 0828
NWS Storm Prediction Center Norman OK
0512 PM CDT Mon May 31 2021
Areas affected...portions of central Texas
Concerning...Severe Thunderstorm Watch 230...
Valid 312212Z - 312345Z
The severe weather threat for Severe Thunderstorm Watch 230
continues.
SUMMARY...The severe threat continues across Severe Thunderstorm
Watch #230. Damaging gusts remain the primary concern with a line of
storms moving across the Watch area for the next few hours.
DISCUSSION...A well-defined MCS with an MCV is propagating eastward
across Severe Thunderstorm Watch #230, mainly south of the
Dallas/Fort Worth Metroplex. The complex is moving into an
environment characterized by 1500 J/kg MLCAPE, driven primarily by
67-70F dewpoints overspread by modest (i.e 6 C/km) mid-level lapse
rates. While instability is rather modest, up to 50 kts of effective
bulk shear is present, with deep-layer shear vectors oriented
roughly orthogonal to the complex. In addition, the MCS is
traversing a relatively broad baroclinic zone, where localized
deep-layer ascent is present and is contributing to storm
organization/sustenance. As such, the convective line is expected to
persist across the remainder of Severe Thunderstorm Watch #230 with
damaging gust potential.
A similar kinematic/thermodynamic downstream environment is expected
east of the ongoing Watch over the next few hours. Storm trends and
ambient environmental conditions will continue to be monitored for
either local watch extensions or a separate WW issuance.
..Squitieri/Guyer.. 05/31/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...HGX...FWD...EWX...
LAT...LON 31109840 31479832 32059796 32499764 32579730 32559670
32379625 32179594 30779620 30459713 30549741 31109840SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 30, 8:59 PM CDT | Mesoscale Discussion | SPC | Carson, Gray, Hansford, Hemphill, Hutchinson, Lipscomb and 6 more | 91 min |
| May 30, 9:17 PM CDT | Severe Thunderstorm Watch | SPC | Armstrong, Carson, Collingsworth, Donley, Gray, Hemphill and 4 more | 5 hr |
| May 30, 9:22 PM CDT | Mesoscale Discussion | SPC | Andrews, Borden, Cochran, Cottle, Crosby, Dawson and 20 more | 83 min |
| May 30, 11:43 PM CDT | Mesoscale Discussion | SPC | Bailey, Cochran, Cottle, Crosby, Dickens, Floyd and 12 more | 92 min |
| May 31, 2:12 AM CDT | Mesoscale Discussion | SPC | Borden, Fisher, Haskell, Howard, Jones, Kent and 5 more | 3 hr |
| May 31, 11:33 AM CDT | Mesoscale Discussion | SPC | Andrews, Borden, Brewster, Cochran, Crane, Crockett and 26 more | 87 min |
| May 31, 12:16 PM CDT | Severe Thunderstorm Watch | SPC | Andrews, Coke, Crane, Crockett, Culberson, Ector and 21 more | 9 hr |
| May 31, 2:15 PM CDT | Mesoscale Discussion | SPC | Bosque, Brown, Callahan, Coleman, Comanche, Coryell and 10 more | 2 hr |
| May 31, 2:54 PM CDT | Severe Thunderstorm Watch | SPC | Bell, Bosque, Comanche, Coryell, Ellis, Erath and 13 more | 4 hr |
| May 31, 3:29 PM CDT | Mesoscale Discussion | SPC | Andrews, Coke, Crane, Crockett, Culberson, Ector and 21 more | 91 min |
| May 31, 5:49 PM CDT | Mesoscale Discussion | SPC | Brewster, Pecos, Terrell | 116 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.