Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 663
The Storm Prediction Center issued this mesoscale discussion at May 17, 2021, 9:44 PM CDT for 21 counties in Texas. It was in force for 91 min.
The area
The outline as issued.
The facts
- Issued
- May 17, 2021, 9:44 PM CDT (02:44 UTC)
- Expired
- May 17, 2021, 11:15 PM CDT
- In force
- 91 min
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 182...183
All 21 counties
Armstrong County, TX, Borden County, TX, Briscoe County, TX, Childress County, TX, Collingsworth County, TX, Cottle County, TX, Crosby County, TX, Dickens County, TX, Donley County, TX, Fisher County, TX, Floyd County, TX, Garza County, TX, Hale County, TX, Hall County, TX, Kent County, TX, King County, TX, Lubbock County, TX, Motley County, TX, Scurry County, TX, Stonewall County, TX, Swisher County, TX
The radar
The Lubbock radar (KLBB), 82 km from the middle of the area, began a volume at 02:42 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
Amarillo Airport, TX (KAMA), launched 00:00Z, 2.7 hours before the alert went out and 202 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
- 1013 J/kg
- Mixed-layer CIN
- -13 J/kg
- Mixed-layer LCL
- 1616 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 139 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.3
The text
As transmitted.
638
ACUS11 KWNS 180245
SWOMCD
SPC MCD 180244
TXZ000-180415-
Mesoscale Discussion 0663
NWS Storm Prediction Center Norman OK
0944 PM CDT Mon May 17 2021
Areas affected...Portions of the TX Panhandle into the TX South
Plains
Concerning...Tornado Watch 182...183...
Valid 180244Z - 180415Z
The severe weather threat for Tornado Watch 182, 183 continues.
SUMMARY...The severe threat continues with ongoing convection,
though a gradual decreasing trend is expected through 04Z. Some
redevelopment is possible later tonight.
DISCUSSION...At 0230Z, pockets of strong convection are ongoing
across southern portions of the TX Panhandle into the TX South
Plains, though a general decreasing trend has been noted over the
past hour. Increasing MLCINH should result in a continued gradual
weakening trend with time, though some instances of large hail and
strong wind gusts will continue to be possible with the remaining
convection, given the still-favorable buoyancy and midlevel lapse
rates.
Later tonight, redevelopment of strong convection may impact at
least southern portions of the MCD area, as a low-level jet becomes
focused into southwest TX. The late-night activity may pose a
hail/wind risk, but any such threat would likely not develop until
closer to 06Z or later.
..Dean.. 05/18/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OUN...SJT...LUB...AMA...MAF...
LAT...LON 32810178 34240191 35050169 35240057 35060021 34239986
33429985 32910017 32580060 32470082 32430132 32520175
32810178SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 17, 7:04 PM CDT | Mesoscale Discussion | SPC | Archer, Bosque, Brown, Clay, Comanche, Eastland and 15 more | 86 min |
| May 17, 7:23 PM CDT | Mesoscale Discussion | SPC | Carson, Dallam, Gray, Hansford, Hartley, Hemphill and 8 more | 2 hr |
| May 17, 7:32 PM CDT | Tornado Watch | SPC | Brown, Callahan, Coke, Coleman, Concho, McCulloch and 4 more | 3 hr |
| May 17, 7:37 PM CDT | Mesoscale Discussion | SPC | Callahan, Coke, Coleman, Glasscock, Howard, Jones and 6 more | 83 min |
| May 17, 8:04 PM CDT | Severe Thunderstorm Watch | SPC | Archer, Clay, Comanche, Eastland, Erath, Hamilton and 11 more | 5 hr |
| May 17, 8:34 PM CDT | Mesoscale Discussion | SPC | Atascosa, Dimmit, Frio, La Salle, McMullen, Maverick and 2 more | 116 min |
| May 17, 9:28 PM CDT | Mesoscale Discussion | SPC | Carson, Collingsworth, Donley, Gray, Hansford, Hemphill and 7 more | 2 hr |
| May 17, 10:23 PM CDT | Mesoscale Discussion | SPC | Archer, Brown, Callahan, Clay, Coke, Coleman and 16 more | 97 min |
| May 17, 10:35 PM CDT | Mesoscale Discussion | SPC | Andrews, Borden, Brewster, Crane, Crockett, Dawson and 13 more | 85 min |
| May 17, 10:58 PM CDT | Severe Thunderstorm Watch | SPC | Andrews, Borden, Brown, Coke, Coleman, Concho and 22 more | 7 hr |
| May 17, 11:37 PM CDT | Mesoscale Discussion | SPC | Bosque, Brown, Comanche, Denton, Eastland, Erath and 9 more | 83 min |
| May 18, 1:02 AM CDT | Mesoscale Discussion | SPC | Brooks, Duval, Jim Hogg | 58 min |
| May 18, 1:29 AM CDT | Mesoscale Discussion | SPC | Coke, Concho, Crane, Crockett, Ector, Glasscock and 13 more | 91 min |
| May 18, 5:07 AM CDT | Mesoscale Discussion | SPC | Coke, Concho, Irion, Reagan, Runnels, Schleicher and 2 more | 53 min |
| May 18, 1:18 PM CDT | Mesoscale Discussion | SPC | Atascosa, Austin, Bastrop, Bexar, Brazos, Burleson and 28 more | 117 min |
| May 18, 1:57 PM CDT | Mesoscale Discussion | SPC | Bailey, Castro, Deaf Smith, Parmer, Randall, Swisher | 3 hr |
| May 18, 2:29 PM CDT | Tornado Watch | SPC | Anderson, Atascosa, Austin, Bastrop, Bexar, Blanco and 30 more | 7 hr |
| May 18, 2:30 PM CDT | Mesoscale Discussion | SPC | Bowie, Camp, Cass, Cherokee, Franklin, Gregg and 12 more | 2 hr |
| May 18, 3:51 PM CDT | Severe Thunderstorm Watch | SPC | Bowie, Camp, Cass, Cherokee, Franklin, Gregg and 11 more | 5 hr |
| May 18, 3:52 PM CDT | Mesoscale Discussion | SPC | Bastrop, Caldwell, Colorado, Fayette, Gonzales, Guadalupe and 2 more | 83 min |
| May 18, 5:10 PM CDT | Mesoscale Discussion | SPC | La Salle, McMullen, Webb | 95 min |
| May 18, 5:39 PM CDT | Mesoscale Discussion | SPC | Bowie, Cass, Gregg, Harrison, Marion, Morris and 1 more | 2 hr |
| May 18, 6:07 PM CDT | Mesoscale Discussion | SPC | Armstrong, Borden, Briscoe, Carson, Castro, Cochran and 17 more | 113 min |
| May 18, 6:13 PM CDT | Mesoscale Discussion | SPC | Austin, Brazos, Burleson, Colorado, DeWitt, Fayette and 14 more | 92 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.