Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 579
The Storm Prediction Center issued this mesoscale discussion at May 10, 2021, 10:28 AM CDT for Bryan County, Choctaw County, Oklahoma; 5 counties in Texas. It was in force for 92 min.
The area
The outline as issued.
The facts
- Issued
- May 10, 2021, 10:28 AM CDT (15:28 UTC)
- Expired
- May 10, 2021, 12:00 PM CDT
- In force
- 92 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
Counties Bryan County, OK, Choctaw County, OK, Delta County, TX, Fannin County, TX, Grayson County, TX, Lamar County, TX, Red River County, TX
The radar
The Dallas/Ft Worth radar (KFWS), 170 km from the middle of the area, began a volume at 15:29 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, 3.5 hours before the alert went out and 150 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
- 675 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- 299 m²/s²
- 0-3 km storm-relative helicity
- 381 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 4.2
The text
As transmitted.
906
ACUS11 KWNS 101529
SWOMCD
SPC MCD 101528
TXZ000-OKZ000-101700-
Mesoscale Discussion 0579
NWS Storm Prediction Center Norman OK
1028 AM CDT Mon May 10 2021
Areas affected...Red River vicinity of southeastern Oklahoma and
northeastern Texas
Concerning...Severe potential...Watch unlikely
Valid 101528Z - 101700Z
Probability of Watch Issuance...20 percent
SUMMARY...Vigorous thunderstorm activity might persist into early
afternoon, perhaps occasionally becoming capable of producing
marginally severe hail. However, potential for this to evolve into
something which could require a severe weather watch currently
appears low.
DISCUSSION...The shallow leading edge of relatively cool/cold
surface-based air has surged into the Rio Grande Valley and adjacent
portions of south central Texas. However, at around the 850 mb
level, a stronger baroclinic zone generally trails across the Texas
South Plains, from a weak wave east of the Wichita Falls vicinity,
and extends east of the wave near the Red River vicinity. An area
of lift associated with enhanced warm advection in the 850-700 mb
layer, above the deeper cold air, appears to be providing support
for ongoing isolated strong thunderstorm development to the east of
the eastward migrating wave. It appears possible that this could
continue into the 17-19Z time frame.
In the presence of steep lower/mid tropospheric lapse rates, moist
air above the frontal inversion appears to be contributing to CAPE
in excess of 1000 J/kg, which probably has been occasionally
supporting marginally severe hail, aided by strong shear in the
cloud bearing layer. As long as vigorous convection persists, this
may continue, but severe weather potential otherwise appears rather
low.
..Kerr/Thompson.. 05/10/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...SHV...TSA...FWD...OUN...
LAT...LON 33919714 34079594 33999514 33509453 33309516 33389622
33409710 33919714SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 9, 8:06 PM CDT | Mesoscale Discussion | SPC | Anderson, Bell, Blanco, Bosque, Burnet, Comal and 32 more | 114 min |
| May 10, 1:04 PM CDT | Mesoscale Discussion | SPC | Edwards, Kinney, Real, Terrell, Val Verde | 116 min |
| May 10, 1:48 PM CDT | Severe Thunderstorm Watch | SPC | Atascosa, Bandera, Bexar, Crockett, Dimmit, Edwards and 14 more | 10 hr |
| May 10, 2:07 PM CDT | Mesoscale Discussion | SPC | Grimes, Houston, Madison, Polk, San Jacinto, Trinity and 2 more | 113 min |
| May 10, 5:47 PM CDT | Mesoscale Discussion | SPC | Brazos, Grimes, Jasper, Montgomery, Polk, San Jacinto and 2 more | 88 min |
| May 10, 6:05 PM CDT | Mesoscale Discussion | SPC | Bee, Dimmit, Duval, Jim Wells, La Salle, Live Oak and 2 more | 2 hr |
Nearby
Mesoscale Discussions in Texas, 2021Mesoscale Discussions in Oklahoma, 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.