Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 643
The Storm Prediction Center issued this mesoscale discussion at May 16, 2021, 6:12 PM CDT for 13 counties in Texas. It was in force for 93 min.
The area
The outline as issued.
The facts
- Issued
- May 16, 2021, 6:12 PM CDT (23:12 UTC)
- Expired
- May 16, 2021, 7:45 PM CDT
- In force
- 93 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 177
Counties Armstrong County, TX, Briscoe County, TX, Carson County, TX, Castro County, TX, Childress County, TX, Deaf Smith County, TX, Donley County, TX, Hall County, TX, Hardeman County, TX, Parmer County, TX, Potter County, TX, Randall County, TX, Swisher County, TX
The radar
The Amarillo radar (KAMA), 52 km from the middle of the area, began a volume at 23:17 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 12:00Z, 11.2 hours before the alert went out and 52 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1470 m above ground
- 0-6 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- -57 m²/s²
- 0-3 km storm-relative helicity
- -16 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
254
ACUS11 KWNS 162313
SWOMCD
SPC MCD 162312
TXZ000-170045-
Mesoscale Discussion 0643
NWS Storm Prediction Center Norman OK
0612 PM CDT Sun May 16 2021
Areas affected...the Texas Panhandle
Concerning...Severe Thunderstorm Watch 177...
Valid 162312Z - 170045Z
The severe weather threat for Severe Thunderstorm Watch 177
continues.
SUMMARY...Threat for mainly isolated large hail will persist through
01Z over the TX Panhandle, after which the primary threat may
transition to damaging wind.
DISCUSSION...Scattered thunderstorms continue along a nearly
stationary outflow boundary across southern portions of the TX
Panhandle as well as along the outflow boundary-dryline intersection
and a short distance southward along the dryline. Storms remain
discrete in character, suggesting large hail remains the primary
short-term threat. The atmosphere is moderately unstable, and a
strengthening southerly low-level jet this evening will augment
mesoscale forcing along the outflow boundary. Storms might become
numerous enough for individual outflows to merge, eventually
supporting the potential for a forward propagating MCS. Should this
evolution occur, the primary threat will transition to damaging wind
by 01Z as storms develop southeast.
..Dial.. 05/16/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OUN...LUB...AMA...
LAT...LON 35790181 34980058 34299969 34110014 34200172 34230264
34490301 35160246 35790181SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 15, 9:09 PM CDT | Mesoscale Discussion | SPC | Armstrong, Briscoe, Carson, Castro, Crosby, Floyd and 11 more | 96 min |
| May 15, 9:32 PM CDT | Mesoscale Discussion | SPC | Andrews, Borden, Crane, Crockett, Dawson, Ector and 11 more | 88 min |
| May 16, 12:15 PM CDT | Mesoscale Discussion | SPC | Anderson, Bastrop, Bell, Brazos, Burleson, Cherokee and 22 more | 2 hr |
| May 16, 3:16 PM CDT | Mesoscale Discussion | SPC | Armstrong, Bailey, Briscoe, Carson, Castro, Cochran and 12 more | 119 min |
| May 16, 3:43 PM CDT | Severe Thunderstorm Watch | SPC | Armstrong, Briscoe, Carson, Castro, Childress, Collingsworth and 19 more | 7 hr |
| May 16, 3:46 PM CDT | Mesoscale Discussion | SPC | Archer, Clay, Cooke, Jack, Montague, Wichita and 1 more | 89 min |
| May 16, 5:52 PM CDT | Mesoscale Discussion | SPC | Glasscock, Howard, Irion, Midland, Reagan, Sterling | 53 min |
| May 16, 6:35 PM CDT | Severe Thunderstorm Watch | SPC | Borden, Coke, Crockett, Dawson, Fisher, Glasscock and 12 more | 4 hr |
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.