Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 1825
The Storm Prediction Center issued this mesoscale discussion at Oct 10, 2021, 8:11 PM CDT for 7 counties in Oklahoma; 43 counties in Texas. It was in force for 64 min.
The area
The outline as issued.
The facts
- Issued
- Oct 10, 2021, 8:11 PM CDT (01:11 UTC)
- Expired
- Oct 10, 2021, 9:15 PM CDT
- In force
- 64 min
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 518
All 50 counties
Atoka County, OK, Bryan County, OK, Carter County, OK, Coal County, OK, Johnston County, OK, Love County, OK, Marshall County, OK, Bell County, TX, Bosque County, TX, Brown County, TX, Collin County, TX, Comanche County, TX, Cooke County, TX, Coryell County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Ellis County, TX, Erath County, TX, Falls County, TX, Fannin County, TX, Freestone County, TX, Grayson County, TX, Hamilton County, TX, Henderson County, TX, Hill County, TX, Hood County, TX, Hopkins County, TX, Hunt County, TX, Jack County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Lampasas County, TX, Leon County, TX, Limestone County, TX, McLennan County, TX, Mills County, TX, Montague County, TX, Navarro County, TX, Palo Pinto County, TX, Parker County, TX, Rains County, TX, Robertson County, TX, Rockwall County, TX, San Saba County, TX, Somervell County, TX, Tarrant County, TX, Van Zandt County, TX, Wise County, TX
The radar
The Dallas/Ft Worth radar (KFWS), 5 km from the middle of the area, began a volume at 01:12 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
Fort Worth, TX (KFWD), launched 00:00Z, 1.2 hours before the alert went out and 24 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
- 1814 J/kg
- Mixed-layer CIN
- -39 J/kg
- Mixed-layer LCL
- 1524 m above ground
- 0-6 km bulk shear
- 52 kt
- 0-1 km storm-relative helicity
- 130 m²/s²
- 0-3 km storm-relative helicity
- 253 m²/s²
- Significant tornado parameter
- 1.5
- Supercell composite
- 11.2
The text
As transmitted.
756
ACUS11 KWNS 110111
SWOMCD
SPC MCD 110111
OKZ000-TXZ000-110215-
Mesoscale Discussion 1825
NWS Storm Prediction Center Norman OK
0811 PM CDT Sun Oct 10 2021
Areas affected...north Texas
Concerning...Tornado Watch 518...
Valid 110111Z - 110215Z
The severe weather threat for Tornado Watch 518 continues.
SUMMARY...Thunderstorms capable of strong winds, large hail, and
tornadoes will move east across the region this evening.
DISCUSSION...Thunderstorms continue to develop and intensity along a
surging dryline across northwest Texas this evening. These
thunderstorms will be capable of producing very strong winds as
strong westerly low-level flow along and west of the dryline is
transported to the ground within thunderstorm downdrafts.
Additionally, ahead of the dryline, low-level theta-e and
instability will be maintained as the nocturnal low-level jet ramps
up and moisture slowly increases, yielding some hail threat.
Additionally, tornadoes cannot be ruled out within the advancing
squall line given the degree of low-level shear across the warm
sector, especially with any kinks that develop along the line. Thus,
despite the loss of diurnal heating, the severe potential will
increase through the evening across much of north Texas.
..Marsh.. 10/11/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...SHV...TSA...FWD...OUN...EWX...SJT...
LAT...LON 31299942 32089886 33159837 33819802 34709677 34729614
34289570 33529539 32169556 31349584 30819686 30899837
31299942SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 10, 7:19 PM CDT | Mesoscale Discussion | SPC | Nowata, Washington | 86 min |
| Oct 10, 9:24 PM CDT | Tornado Watch | SPC | Adair, Cherokee, Choctaw, Craig, Creek, Delaware and 19 more | 5 hr |
| Oct 10, 10:16 PM CDT | Mesoscale Discussion | SPC | Atoka, Bryan, Choctaw, Coal, Johnston, McCurtain and 1 more | 59 min |
| Oct 10, 11:07 PM CDT | Tornado Watch | SPC | McCurtain | 5 hr |
| Oct 10, 11:32 PM CDT | Mesoscale Discussion | SPC | Adair, Cherokee, Choctaw, Craig, Delaware, Haskell and 14 more | 118 min |
| Oct 11, 12:58 AM CDT | Mesoscale Discussion | SPC | Anderson, Bowie, Camp, Cass, Cherokee, Gregg and 13 more | 92 min |
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.